Airplane Pilot's As Physicists

[Le Chaud Lapin]

Hi All,

There is a long discussion ongoing in rec.aviation.piloting about what
causes lift on a plane. You can read from the link below. Please
note that about 80% of the post are mostly ad hominem attacks and
should be ignored. There are some small bits of real discussion.

http://groups.google.com/group/rec.aviation.piloting/browse_frm/thread/b85a49e900a0c791/bb11fa289cd7864a#bb11fa289cd7864a

I am an electrical engineer with experience in analag design and
software, with math and physics background that you would expect of an
electrical engineer.

There are many points made in the discussion, but I would like to
focus on one in particular for the sake of progress.

There are people in the pilot's group, who think that lift on a wing
is analyzed as such:

1. There is air on outside of top of wing that is pushing down, but
reduced because of aerodynamics.
2. The *inside* of the wing contains air pushing up against the
underside of top of wing .
3. Let us ignore that the same air inside the wing pushes down on the
overside of bottom part of wing.
3. The difference in pressure against the underside of the top wing on
the inside of wing and top of wing on outside, is what gives plane
lift.

Note that they ignore the pressure inside the wing that pushes
downward on the wing.

I am trying to convince them that, if there is air on the inside of
the wing, it pushes against all sides of the inside of the wing,
including both top underside and bottom overside, and thereby
nullifying any effect it would have on the wing. Lift is caused by a
difference in pressure between the underside of the bottom of the
wing, and the overside of the top of the wing.

I count 8-9 people in the group who are utterly convinced that I am
inept at physics, mathematics, etc.

Note that some of these people have been flying aircraft for years,
even decades, while I am still a student pilot.

Comments from anyone who knows physics welcome.

-Le Chaud Lapin-

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
ps.com:

> Hi All,
>
> There is a long discussion ongoing in rec.aviation.piloting about what
> causes lift on a plane.


No, there isn't. There are people who know perfectly well how it works
trying to tell a ccouple of k00ks who think they know


Bertie
>

[Randy Poe]

On Oct 9, 4:08 pm, Le Chaud Lapin > wrote:
> Hi All,
>
> There is a long discussion ongoing in rec.aviation.piloting about what
> causes lift on a plane.

Heh. I know the argument. I think it's broken out here (sci.physics)
many times.

(a) It's the Bernoulli effect due to the shape of the
wing cross-section, the way we were all taught as kids.

(b) No, it's just the angle of attack.

I'm no expert, but I heard enough in similar arguments here
to convince me that the angle-of-attack people are right and
the shape of the wing has more to do with controlling
turbulence.

> There are people in the pilot's group, who think that lift on a wing
> is analyzed as such:
>
> 1. There is air on outside of top of wing that is pushing down, but
> reduced because of aerodynamics.
> 2. The *inside* of the wing contains air pushing up against the
> underside of top of wing .

Er... that's a new one. OK, I haven't heard this argument
then.

> 3. Let us ignore that the same air inside the wing pushes down on the
> overside of bottom part of wing.
> 4. The difference in pressure against the underside of the top wing on
> the inside of wing and top of wing on outside, is what gives plane
> lift.

You can consider that last just a definition of lift. You
won't get lift unless the upward forces are stronger than
then downward forces.

> Note that they ignore the pressure inside the wing that pushes
> downward on the wing.

A wing doesn't need to be hollow to fly.

> I am trying to convince them that, if there is air on the inside of
> the wing, it pushes against all sides of the inside of the wing,
> including both top underside and bottom overside, and thereby
> nullifying any effect it would have on the wing. Lift is caused by a
> difference in pressure between the underside of the bottom of the
> wing, and the overside of the top of the wing.
>
> I count 8-9 people in the group who are utterly convinced that I am
> inept at physics, mathematics, etc.
>
> Note that some of these people have been flying aircraft for years,
> even decades, while I am still a student pilot.
>
> Comments from anyone who knows physics welcome.

As I said, I lean toward the angle-of-attack arguments now. Take
a flat rectangle, tilt it into the wind. The wind blows against the
front which is also the bottom, not the back/top. So the
forces are on the bottom.

Why does that translate into lift? I forget the exact arguments
but from first principles if the effect is to change the direction
of the incoming air molecules, then by conservation of
momentum that translates into equal and opposite change
of momentum of the surface, i.e. pressure with an upward
component.

- Randy

[Bertie the Bunyip[_19_]]

Randy Poe > wrote in
oups.com:

> On Oct 9, 4:08 pm, Le Chaud Lapin > wrote:
>> Hi All,
>>
>> There is a long discussion ongoing in rec.aviation.piloting about
what
>> causes lift on a plane.
>
> Heh. I know the argument. I think it's broken out here (sci.physics)
> many times.
>
> (a) It's the Bernoulli effect due to the shape of the
> wing cross-section, the way we were all taught as kids.
>
> (b) No, it's just the angle of attack.
>
> I'm no expert, but I heard enough in similar arguments here
> to convince me that the angle-of-attack people are right and
> the shape of the wing has more to do with controlling
> turbulence.
>
>> There are people in the pilot's group, who think that lift on a wing
>> is analyzed as such:
>>
>> 1. There is air on outside of top of wing that is pushing down, but
>> reduced because of aerodynamics.
>> 2. The *inside* of the wing contains air pushing up against the
>> underside of top of wing .
>
> Er... that's a new one. OK, I haven't heard this argument
> then.
>
>> 3. Let us ignore that the same air inside the wing pushes down on the
>> overside of bottom part of wing.
>> 4. The difference in pressure against the underside of the top wing
on
>> the inside of wing and top of wing on outside, is what gives plane
>> lift.
>
> You can consider that last just a definition of lift. You
> won't get lift unless the upward forces are stronger than
> then downward forces.
>
>> Note that they ignore the pressure inside the wing that pushes
>> downward on the wing.
>
> A wing doesn't need to be hollow to fly.
>
>> I am trying to convince them that, if there is air on the inside of
>> the wing, it pushes against all sides of the inside of the wing,
>> including both top underside and bottom overside, and thereby
>> nullifying any effect it would have on the wing. Lift is caused by a
>> difference in pressure between the underside of the bottom of the
>> wing, and the overside of the top of the wing.
>>
>> I count 8-9 people in the group who are utterly convinced that I am
>> inept at physics, mathematics, etc.
>>
>> Note that some of these people have been flying aircraft for years,
>> even decades, while I am still a student pilot.
>>
>> Comments from anyone who knows physics welcome.
>
> As I said, I lean toward the angle-of-attack arguments now. Take
> a flat rectangle, tilt it into the wind. The wind blows against the
> front which is also the bottom, not the back/top. So the
> forces are on the bottom.
>
> Why does that translate into lift? I forget the exact arguments
> but from first principles if the effect is to change the direction
> of the incoming air molecules, then by conservation of
> momentum that translates into equal and opposite change
> of momentum of the surface, i.e. pressure with an upward
> component.
>
> - Randy
>
>

Well, thanks be to god that that';s been authoritatively setttled.


Bertie

[Le Chaud Lapin]

On Oct 9, 3:22 pm, Randy Poe > wrote:
> On Oct 9, 4:08 pm, Le Chaud Lapin > wrote:
>
> > Hi All,
>
> > There is a long discussion ongoing in rec.aviation.piloting about what
> > causes lift on a plane.
>
> Heh. I know the argument. I think it's broken out here (sci.physics)
> many times.
>
> (a) It's the Bernoulli effect due to the shape of the
> wing cross-section, the way we were all taught as kids.
>
> (b) No, it's just the angle of attack.
>
> I'm no expert, but I heard enough in similar arguments here
> to convince me that the angle-of-attack people are right and
> the shape of the wing has more to do with controlling
> turbulence.
>
> > There are people in the pilot's group, who think that lift on a wing
> > is analyzed as such:
>
> > 1. There is air on outside of top of wing that is pushing down, but
> > reduced because of aerodynamics.
> > 2. The *inside* of the wing contains air pushing up against the
> > underside of top of wing .
>
> Er... that's a new one. OK, I haven't heard this argument
> then.
>
> > 3. Let us ignore that the same air inside the wing pushes down on the
> > overside of bottom part of wing.
> > 4. The difference in pressure against the underside of the top wing on
> > the inside of wing and top of wing on outside, is what gives plane
> > lift.
>
> You can consider that last just a definition of lift. You
> won't get lift unless the upward forces are stronger than
> then downward forces.
>
> > Note that they ignore the pressure inside the wing that pushes
> > downward on the wing.
>
> A wing doesn't need to be hollow to fly.
>
> > I am trying to convince them that, if there is air on the inside of
> > the wing, it pushes against all sides of the inside of the wing,
> > including both top underside and bottom overside, and thereby
> > nullifying any effect it would have on the wing. Lift is caused by a
> > difference in pressure between the underside of the bottom of the
> > wing, and the overside of the top of the wing.

Thanks Randy,

But before we talk about what causes lift on the plane, we should
clear up the basic physics 1st. Note that what I have described above
has nothing to do with airplanes really.

If you read carefully, the premise of what they are saying is that, if
you have, for example, a sealed jar with air in it, you are permitted
to consider the air on the _inside_ of the jar, pushing up on the lid
as contributing to a force to lift the jar off the ground, but you are
not allowed to consider the air on the _inside_ of the jar, pushing
down on the jar un the upper surface of the bottom of the jar.

-Le Chaud Lapin-

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
ups.com:

> On Oct 9, 3:22 pm, Randy Poe > wrote:
>> On Oct 9, 4:08 pm, Le Chaud Lapin > wrote:
>>
>> > Hi All,
>>
>> > There is a long discussion ongoing in rec.aviation.piloting about
what
>> > causes lift on a plane.
>>
>> Heh. I know the argument. I think it's broken out here (sci.physics)
>> many times.
>>
>> (a) It's the Bernoulli effect due to the shape of the
>> wing cross-section, the way we were all taught as kids.
>>
>> (b) No, it's just the angle of attack.
>>
>> I'm no expert, but I heard enough in similar arguments here
>> to convince me that the angle-of-attack people are right and
>> the shape of the wing has more to do with controlling
>> turbulence.
>>
>> > There are people in the pilot's group, who think that lift on a
wing
>> > is analyzed as such:
>>
>> > 1. There is air on outside of top of wing that is pushing down, but
>> > reduced because of aerodynamics.
>> > 2. The *inside* of the wing contains air pushing up against the
>> > underside of top of wing .
>>
>> Er... that's a new one. OK, I haven't heard this argument
>> then.
>>
>> > 3. Let us ignore that the same air inside the wing pushes down on
the
>> > overside of bottom part of wing.
>> > 4. The difference in pressure against the underside of the top wing
on
>> > the inside of wing and top of wing on outside, is what gives plane
>> > lift.
>>
>> You can consider that last just a definition of lift. You
>> won't get lift unless the upward forces are stronger than
>> then downward forces.
>>
>> > Note that they ignore the pressure inside the wing that pushes
>> > downward on the wing.
>>
>> A wing doesn't need to be hollow to fly.
>>
>> > I am trying to convince them that, if there is air on the inside of
>> > the wing, it pushes against all sides of the inside of the wing,
>> > including both top underside and bottom overside, and thereby
>> > nullifying any effect it would have on the wing. Lift is caused by
a
>> > difference in pressure between the underside of the bottom of the
>> > wing, and the overside of the top of the wing.
>
> Thanks Randy,
>
> But before we talk about what causes lift on the plane, we should
> clear up the basic physics 1st. Note that what I have described above
> has nothing to do with airplanes really.
>
> If you read carefully, the premise of what they are saying is that, if
> you have, for example, a sealed jar with air in it, you are permitted
> to consider the air on the _inside_ of the jar, pushing up on the lid
> as contributing to a force to lift the jar off the ground, but you are
> not allowed to consider the air on the _inside_ of the jar, pushing
> down on the jar un the upper surface of the bottom of the jar.
>


Oh for ****'s sake.

You push on something it moves, right?

Everone already knows that, Stephen hawkings.


While you're trying to agitate in a physics froup why don;'t you ask
them how it's physically possible to get your head that far up your own
ass.

Bertie

[Le Chaud Lapin]

On Oct 9, 3:31 pm, Sam Wormley > wrote:
> Ref:http://www.physlink.com/Education/AskExperts/ae627.cfm
>
> Question:
> If an airplane wing provides lift (an airfoil), how does a plane fly
> upside down?
>
> Asked by: Lee Hathcox
>
> Answer:
> The same way that your hand gets pulled upwards if you stick it out the
> car window and tilt it. The lift of an airfoil is determined by two
> things - the shape of the wing, and it's angle of attack. Angle of
> attack is the angle between the flat surface of the wing, and the
> oncoming air stream. So when I roll the airplane upside down... if I
> push the stick forward, that pushes the nose of the plane towards the
> sky, and increases my angle of attack, even though I'm upside down. So,
> the shape of the wing doesn't change, and it pulls me down, but the
> angle of attack I control, and I can make it push me up. So when the
> lift from angle of attack in the up direction, exceeds the lift from
> the shape of the wing, in the down direction, you can balance the force
> of gravity acting on the plane. You can see the influence of angle of
> attack, because even if your hand isn't shaped like a wing, you can see
> how the angle and the force of the air push it in whichever direction
> you choose.

Even though this (new) thread is not about what causes a wing to lift,
I just wanted to say for the record that I agree with this answer,
that it is both AoA and curvature of the wing.

-Le Chaud Lapin-

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
oups.com:

> On Oct 9, 3:31 pm, Sam Wormley > wrote:
>> Ref:http://www.physlink.com/Education/AskExperts/ae627.cfm
>>
>> Question:
>> If an airplane wing provides lift (an airfoil), how does a plane fly
>> upside down?
>>
>> Asked by: Lee Hathcox
>>
>> Answer:
>> The same way that your hand gets pulled upwards if you stick it out
the
>> car window and tilt it. The lift of an airfoil is determined by two
>> things - the shape of the wing, and it's angle of attack. Angle of
>> attack is the angle between the flat surface of the wing, and the
>> oncoming air stream. So when I roll the airplane upside down... if I
>> push the stick forward, that pushes the nose of the plane towards the
>> sky, and increases my angle of attack, even though I'm upside down.
So,
>> the shape of the wing doesn't change, and it pulls me down, but the
>> angle of attack I control, and I can make it push me up. So when the
>> lift from angle of attack in the up direction, exceeds the lift from
>> the shape of the wing, in the down direction, you can balance the
force
>> of gravity acting on the plane. You can see the influence of angle of
>> attack, because even if your hand isn't shaped like a wing, you can
see
>> how the angle and the force of the air push it in whichever direction
>> you choose.
>
> Even though this (new) thread is not about what causes a wing to lift,
> I just wanted to say for the record that I agree with this answer,
> that it is both AoA and curvature of the wing.
>


Quick, call NASA.



Bertie

[Jim Logajan]

Le Chaud Lapin > wrote:
> I am trying to convince them that, if there is air on the inside of
> the wing, it pushes against all sides of the inside of the wing,
> including both top underside and bottom overside, and thereby
> nullifying any effect it would have on the wing.

You are trying to convince one person - there is no plural.

Just for the record, I pointed the OP at the following NASA web pages and
after first thanking me, has decided NASA's explanation is somehow suspect:

http://www.grc.nasa.gov/WWW/K-12/airplane/lift1.html
http://www.grc.nasa.gov/WWW/K-12/airplane/right2.html
http://www.grc.nasa.gov/WWW/K-12/airplane/downwash.html

Note follow-ups set to sci.physics only.

[Mxsmanic]

Randy Poe writes:

> As I said, I lean toward the angle-of-attack arguments now. Take
> a flat rectangle, tilt it into the wind. The wind blows against the
> front which is also the bottom, not the back/top. So the
> forces are on the bottom.

The essential feature of an airfoil is that it twists the flow of air as it
passes (or as the airfoil passes through still air, which is equivalent, and
that's how it works in airplanes). The air is accelerated downward, and this
engenders an equal and opposite force that is lift.

So how does a wing produce lift? By twisting air downwards, creating a
downwash. Accelerating a mass of air downwards tends to accelerate the wing
upwards, and there's your lift.

The theory gets more complicated when you try to explain exactly how and why
airfoils twist an airflow. Just looking at a flat board with a positive angle
of attack, you'd think that it would twist the air, and that's exactly what it
does. But the devil is in the details.

Fortunately, aviators don't have to know or care about the details. All they
need to know is that a wing with a positive angle of attack (and below the
stall angle) will generate lift.

Lift, like so many other phenomena in physics, can be analyzed and explained
in a number of different, equally valid ways, depending on one's point of
view. All analyses and explanations converge on the same reality. Of course,
some explanations of lift are just plain incorrect, and unfortunately a few of
them are quite widespread.

[Gatt]

"Le Chaud Lapin" > wrote in message
ps.com...

> I am an electrical engineer with experience in analag

That would be "analog" there, wouldn't it, engineer? Now, think about how
"attention to detail" applies to math.

> I count 8-9 people in the group who are utterly convinced that I am inept
> at physics, mathematics, etc.

Nobody's saying you're inept at anything; just arrogant about your
assumptions, and wrong, and quite possibly dishonest about your identity.

Taking on the science of NASA, for example, challenges the kind of people
who put men on the moon, shuttle aircraft into space and back, and robots on
Mars. What I'm saying is, they've proven their ability to do math and
physics. You're talking about two pieces of paper on a table or whatever,
admitting you don't fully understand aerodynamics, and then challenging the
kind of people who did research using SR-71 blackbirds and spacecraft.

....in a pilots' forum. What in hell kind of response did you possibly
expect?

-c

[Mxsmanic]

Le Chaud Lapin writes:

> If you read carefully, the premise of what they are saying is that, if
> you have, for example, a sealed jar with air in it, you are permitted
> to consider the air on the _inside_ of the jar, pushing up on the lid
> as contributing to a force to lift the jar off the ground, but you are
> not allowed to consider the air on the _inside_ of the jar, pushing
> down on the jar un the upper surface of the bottom of the jar.

The atmosphere is not a sealed jar. The source of air pressure in the
atmosphere is gravity, not confinement and kinetic energy.

[Mxsmanic]

Sam Wormley writes:

> The same way that your hand gets pulled upwards if you stick it out the
> car window and tilt it. The lift of an airfoil is determined by two
> things - the shape of the wing, and it's angle of attack.

Actually, only the angle of attack matters.

> So when the lift from angle of attack in the up direction, exceeds the lift from
> the shape of the wing ...

All of the lift comes from the positive angle of attack.

> Answered by: Frank DiBonaventuro, B.S., Physics, The Citadel, Air Force
> officer

I guess even the Citadel is passing on some bad information.

[Mxsmanic]

Le Chaud Lapin writes:

> Even though this (new) thread is not about what causes a wing to lift,
> I just wanted to say for the record that I agree with this answer,
> that it is both AoA and curvature of the wing.

It's just AOA.

[Gatt]

"Randy Poe" > wrote in message
oups.com...

> As I said, I lean toward the angle-of-attack arguments now. Take
> a flat rectangle, tilt it into the wind. The wind blows against the
> front which is also the bottom, not the back/top. So the
> forces are on the bottom.

The day the physics guys were passing out good wing designs, the aerospace
designers were all out drinking beer, which is why every airplane since the
Wright flyer has camber when they could have just used flat plywood.

-c

[Gatt]

"Le Chaud Lapin" > wrote in message
ups.com...

> If you read carefully, the premise of what they are saying is that, if
> you have, for example, a sealed jar with air in it, you are permitted
> to consider the air on the _inside_ of the jar,

WTF is he talking about? Nobody said anything about air -inside- of a wing.

-c

[Robert M. Gary]

I don't understand the subject of the post. "Airplane Pilot's" what?
Why are you using a possessive noun here?

-Robert

[Bertie the Bunyip[_19_]]

Mxsmanic > wrote in
:

> Sam Wormley writes:
>
>> The same way that your hand gets pulled upwards if you stick it out
>> the car window and tilt it. The lift of an airfoil is determined by
>> two things - the shape of the wing, and it's angle of attack.
>
> Actually, only the angle of attack matters.


Nope, wrong again fjukkwit.


>
>> So when the lift from angle of attack in the up direction, exceeds
>> the lift from the shape of the wing ...
>
> All of the lift comes from the positive angle of attack.


Nope, worng again.


>
>> Answered by: Frank DiBonaventuro, B.S., Physics, The Citadel, Air
>> Force officer
>
> I guess even the Citadel is passing on some bad information.
>

Nope.


They fly, you don;t.

You never will,.
Nor wil your sockpuppets.

Bertie

[Bertie the Bunyip[_19_]]

Mxsmanic > wrote in
:

> Le Chaud Lapin writes:
>
>> Even though this (new) thread is not about what causes a wing to lift,
>> I just wanted to say for the record that I agree with this answer,
>> that it is both AoA and curvature of the wing.
>
> It's just AOA.
>

Nope.

bertie

[Bertie the Bunyip[_19_]]

Mxsmanic > wrote in
:

> Randy Poe writes:
>
>> As I said, I lean toward the angle-of-attack arguments now. Take
>> a flat rectangle, tilt it into the wind. The wind blows against the
>> front which is also the bottom, not the back/top. So the
>> forces are on the bottom.
>
> The essential feature of an airfoil is that it twists the flow of air
> as it passes (or as the airfoil passes through still air, which is
> equivalent, and that's how it works in airplanes). The air is
> accelerated downward, and this engenders an equal and opposite force
> that is lift.
>
> So how does a wing produce lift? By twisting air downwards, creating
> a downwash. Accelerating a mass of air downwards tends to accelerate
> the wing upwards, and there's your lift.
>
> The theory gets more complicated when you try to explain exactly how
> and why airfoils twist an airflow. Just looking at a flat board with
> a positive angle of attack, you'd think that it would twist the air,
> and that's exactly what it does. But the devil is in the details.
>
> Fortunately, aviators don't have to know or care about the details.
> All they need to know is that a wing with a positive angle of attack
> (and below the stall angle) will generate lift.
>
> Lift, like so many other phenomena in physics, can be analyzed and
> explained in a number of different, equally valid ways, depending on
> one's point of view. All analyses and explanations converge on the
> same reality. Of course, some explanations of lift are just plain
> incorrect, and unfortunately a few of them are quite widespread.
>




Nope


Bertie

[Le Chaud Lapin]

On Oct 9, 4:29 pm, "Gatt" > wrote:
> "Le Chaud Lapin" > wrote in glegroups.com...

> Taking on the science of NASA, for example, challenges the kind of people
> who put men on the moon, shuttle aircraft into space and back, and robots on
> Mars. What I'm saying is, they've proven their ability to do math and
> physics. You're talking about two pieces of paper on a table or whatever,
> admitting you don't fully understand aerodynamics, and then challenging the
> kind of people who did research using SR-71 blackbirds and spacecraft.

My initial assertion was that the experts were not in agreement about
causes lift. Many posters said that I was wrong, that there was total
agreement, that I was mistaken.

> ...in a pilots' forum. What in hell kind of response did you possibly
> expect?

A little bit more focus on the physics, a loss less focus on the
poster.

And with regard to the demonstration I presented in my original post,
I was expecting at least one pilot to give a correct explanation why
the lower paper is lifted off the ground, and not only has anyone
given a correct explanation, but no one has given any explanation at
all.

-Le Chaud Lapin-

[Dudley Henriques[_2_]]

Bertie the Bunyip wrote:
> Mxsmanic > wrote in
> :
>
>> Sam Wormley writes:
>>
>>> The same way that your hand gets pulled upwards if you stick it out
>>> the car window and tilt it. The lift of an airfoil is determined by
>>> two things - the shape of the wing, and it's angle of attack.
>> Actually, only the angle of attack matters.
>
>
> Nope, wrong again fjukkwit.
>
>
>>> So when the lift from angle of attack in the up direction, exceeds
>>> the lift from the shape of the wing ...
>> All of the lift comes from the positive angle of attack.
>
>
> Nope, worng again.
>
>
>>> Answered by: Frank DiBonaventuro, B.S., Physics, The Citadel, Air
>>> Force officer
>> I guess even the Citadel is passing on some bad information.
>>
>
> Nope.
>
>
> They fly, you don;t.
>
> You never will,.
> Nor wil your sockpuppets.
>
> Bertie
>

Wait a second here; couldn't a sock puppet fly if we used a latex liner
inside, filled it with Helium and tied it at the bottom before we let it
loose???
:-)

--
Dudley Henriques

[Bertie the Bunyip[_19_]]

Mxsmanic > wrote in
:

> Le Chaud Lapin writes:
>
>> If you read carefully, the premise of what they are saying is that, if
>> you have, for example, a sealed jar with air in it, you are permitted
>> to consider the air on the _inside_ of the jar, pushing up on the lid
>> as contributing to a force to lift the jar off the ground, but you are
>> not allowed to consider the air on the _inside_ of the jar, pushing
>> down on the jar un the upper surface of the bottom of the jar.
>
> The atmosphere is not a sealed jar. The source of air pressure in the
> atmosphere is gravity, not confinement and kinetic energy.
>

You are an idiot.


Bertie

[Jim Logajan]

Mxsmanic > wrote:
> Le Chaud Lapin writes:
>
>> Even though this (new) thread is not about what causes a wing to lift,
>> I just wanted to say for the record that I agree with this answer,
>> that it is both AoA and curvature of the wing.
>
> It's just AOA.

*Sigh*

Then why does lift increase even though the AOA is fixed as a plane nears
the ground? (a.k.a. Ground effect.)

[Le Chaud Lapin]

On Oct 9, 4:37 pm, "Robert M. Gary" > wrote:
> I don't understand the subject of the post. "Airplane Pilot's" what?
> Why are you using a possessive noun here?
>
> -Robert

Typo.

-Le Chaud Lapin-

[Mxsmanic]

Gatt writes:

> The day the physics guys were passing out good wing designs, the aerospace
> designers were all out drinking beer, which is why every airplane since the
> Wright flyer has camber when they could have just used flat plywood.

Some wings do not have camber. Anyway, the purpose of the curve is to reduce
drag and increase the stall angle, not to produce lift.

[Le Chaud Lapin]

On Oct 9, 4:35 pm, "Gatt" > wrote:
> "Le Chaud Lapin" > wrote in oglegroups.com...
>
> > If you read carefully, the premise of what they are saying is that, if
> > you have, for example, a sealed jar with air in it, you are permitted
> > to consider the air on the _inside_ of the jar,
>
> WTF is he talking about? Nobody said anything about air -inside- of a wing.

On Oct 9, 1:00 pm, Phil > wrote:
> Le Chaud Lapin wrote:
> > > If you
> > > don't like the concept that the top of the wing is being sucked upward
> > > by that lower pressure
>
> > It is not a matter of whether I like it or not. It is something that
> > simply does not happen. There is no sucking force.

> I think you mis-understood me here. When I say the air below the line
> is pressing upward, I am not referring to the air pressing upward on
> the bottom of the wing. I am referring to the air _inside_ the wing
> pressing upward on the underside of the top surface of the wing. The
> air above the wing top surface has lower than normal pressure. The
> air inside the wing has normal pressure. So it presses upward on the
> top surface of the wing. This is lift generated by the top surface of
> the wing.

> Phil

-Le Chaud Lapin-

[Bertie the Bunyip[_19_]]

Dudley Henriques > wrote in
:

> Bertie the Bunyip wrote:
>> Mxsmanic > wrote in
>> :
>>
>>> Sam Wormley writes:
>>>
>>>> The same way that your hand gets pulled upwards if you stick it out
>>>> the car window and tilt it. The lift of an airfoil is determined by
>>>> two things - the shape of the wing, and it's angle of attack.
>>> Actually, only the angle of attack matters.
>>
>>
>> Nope, wrong again fjukkwit.
>>
>>
>>>> So when the lift from angle of attack in the up direction, exceeds
>>>> the lift from the shape of the wing ...
>>> All of the lift comes from the positive angle of attack.
>>
>>
>> Nope, worng again.
>>
>>
>>>> Answered by: Frank DiBonaventuro, B.S., Physics, The Citadel, Air
>>>> Force officer
>>> I guess even the Citadel is passing on some bad information.
>>>
>>
>> Nope.
>>
>>
>> They fly, you don;t.
>>
>> You never will,.
>> Nor wil your sockpuppets.
>>
>> Bertie
>>
>
> Wait a second here; couldn't a sock puppet fly if we used a latex
liner
> inside, filled it with Helium and tied it at the bottom before we let
it
> loose??


They're already full of hot air. /It's only a matter of harnessing that!

Bertie
>

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
ups.com:

> On Oct 9, 4:29 pm, "Gatt" > wrote:
>> "Le Chaud Lapin" > wrote in
>> glegroups.com...
>
>> Taking on the science of NASA, for example, challenges the kind of
>> people who put men on the moon, shuttle aircraft into space and back,
>> and robots on Mars. What I'm saying is, they've proven their ability
>> to do math and physics. You're talking about two pieces of paper on
>> a table or whatever, admitting you don't fully understand
>> aerodynamics, and then challenging the kind of people who did
>> research using SR-71 blackbirds and spacecraft.
>
> My initial assertion was that the experts were not in agreement about
> causes lift. Many posters said that I was wrong, that there was total
> agreement, that I was mistaken.
>
>> ...in a pilots' forum. What in hell kind of response did you
>> possibly expect?
>
> A little bit more focus on the physics, a loss less focus on the
> poster.
>
> And with regard to the demonstration I presented in my original post,
> I was expecting at least one pilot to give a correct explanation why
> the lower paper is lifted off the ground, and not only has anyone
> given a correct explanation, but no one has given any explanation at
> all.=


Yeah, right mr sockpuppet.



Bertie

[Bertie the Bunyip[_19_]]

Mxsmanic > wrote in
:

> Gatt writes:
>
>> The day the physics guys were passing out good wing designs, the
>> aerospace designers were all out drinking beer, which is why every
>> airplane since the Wright flyer has camber when they could have just
>> used flat plywood.
>
> Some wings do not have camber.


Name one, aside from a chuck glider.

(and good chuck gliders have camber, BTW, fjukkwit



Anyway, the purpose of the curve is to
> reduce drag and increase the stall angle, not to produce lift.
>


Nope.


Bertie

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
ups.com:

> On Oct 9, 4:37 pm, "Robert M. Gary" > wrote:
>> I don't understand the subject of the post. "Airplane Pilot's" what?
>> Why are you using a possessive noun here?
>>
>> -Robert
>
> Typo.
>

idiot.


Bertie

[Gatt]

"Bertie the Bunyip" > wrote in message
...
> Mxsmanic > wrote in
> :
>
>> Le Chaud Lapin writes:
>>
>>> Even though this (new) thread is not about what causes a wing to lift,
>>> I just wanted to say for the record that I agree with this answer,
>>> that it is both AoA and curvature of the wing.
>>
>> It's just AOA.
>>
> Nope.

There goes my Lapin = MX theory. Apologies to Chaud are probably in order.
(I probably apologize?)

-c

[Jim Stewart]

Mxsmanic wrote:
> Le Chaud Lapin writes:
>
>> If you read carefully, the premise of what they are saying is that, if
>> you have, for example, a sealed jar with air in it, you are permitted
>> to consider the air on the _inside_ of the jar, pushing up on the lid
>> as contributing to a force to lift the jar off the ground, but you are
>> not allowed to consider the air on the _inside_ of the jar, pushing
>> down on the jar un the upper surface of the bottom of the jar.
>
> The atmosphere is not a sealed jar. The source of air pressure in the
> atmosphere is gravity, not confinement and kinetic energy.

I feel as though I am in the presence of
genius.....

[Gatt]

"Le Chaud Lapin" > wrote in message
ups.com...

> My initial assertion was that the experts were not in agreement about
> causes lift. Many posters said that I was wrong, that there was >total
> agreement, that I was mistaken.

Who said there was "total agreement"? Try to be scientifically exact here.
Can you?

>> ...in a pilots' forum. What in hell kind of response did you possibly
>> expect?
>
> A little bit more focus on the physics, a loss less focus on the poster.

If you expect pilots and aircraft professionals to take time to indulge your
theories, you will learn to treat them with respect or you will take your
lumps. Nobody's obligated whatsoever to focus on your physics or to treat
you whatever manner you prefer regarldess of how you present yourself.

> And with regard to the demonstration I presented in my original post, I
> was expecting at least one pilot to give a correct explanation >why the
> lower paper is lifted off the ground, and not only has anyone given a
> correct explanation, but no one has given any explanation at
> all.

Imagine that. Even the flight instructors are ignoring you. See my
previous statement.

-c

[Bertie the Bunyip[_19_]]

"Gatt" > wrote in
:

>
> "Bertie the Bunyip" > wrote in message
> ...
>> Mxsmanic > wrote in
>> :
>>
>>> Le Chaud Lapin writes:
>>>
>>>> Even though this (new) thread is not about what causes a wing to
>>>> lift, I just wanted to say for the record that I agree with this
>>>> answer, that it is both AoA and curvature of the wing.
>>>
>>> It's just AOA.
>>>
>> Nope.
>
> There goes my Lapin = MX theory. Apologies to Chaud are probably in
> order. (I probably apologize?)
>
> -c
>
>

Why, cuz they're adopting different arguments?


nah, standard sock tactic. If his creation looked too much like himself
it'd be too obvious.


Bertie
>

[Bertie the Bunyip[_19_]]

Jim Stewart > wrote in news:4-
:

> Mxsmanic wrote:
>> Le Chaud Lapin writes:
>>
>>> If you read carefully, the premise of what they are saying is that, if
>>> you have, for example, a sealed jar with air in it, you are permitted
>>> to consider the air on the _inside_ of the jar, pushing up on the lid
>>> as contributing to a force to lift the jar off the ground, but you are
>>> not allowed to consider the air on the _inside_ of the jar, pushing
>>> down on the jar un the upper surface of the bottom of the jar.
>>
>> The atmosphere is not a sealed jar. The source of air pressure in the
>> atmosphere is gravity, not confinement and kinetic energy.
>
> I feel as though I am in the presence of
> genius.....
>

Take a tums, it'll get better


Bertie

[Mxsmanic]

Jim Logajan writes:

> Then why does lift increase even though the AOA is fixed as a plane nears
> the ground? (a.k.a. Ground effect.)

Ground effect, as the name implies, is a consequence of the interaction
between an airfoil and a moving ground plane, and not of the airfoil alone.

[Gatt]

"Robert M. Gary" > wrote in message
oups.com...
>I don't understand the subject of the post. "Airplane Pilot's" what?
> Why are you using a possessive noun here?

....but not "physicists" which ends with the same two letters.

Science and engineering require precision and attention to detail. I was a
little surprised too. When you're defending the accuracy of your statements
it helps if you look like you have your poop in a group.

-c

[Bertie the Bunyip[_19_]]

Mxsmanic > wrote in
:

> Jim Logajan writes:
>
>> Then why does lift increase even though the AOA is fixed as a plane
>> nears the ground? (a.k.a. Ground effect.)
>
> Ground effect, as the name implies, is a consequence of the
> interaction between an airfoil and a moving ground plane, and not of
> the airfoil alone.
>

Awe inspiring.



Fjukkwit.


Bertie

[Gatt]

"Bertie the Bunyip" > wrote in message
...
> "Gatt" > wrote in

>> There goes my Lapin = MX theory. Apologies to Chaud are probably in
>> order. (I probably apologize?)

> nah, standard sock tactic. If his creation looked too much like himself
> it'd be too obvious.

Ah, unfortunately I'm not up on sock tactics.

-c

[Bertie the Bunyip[_19_]]

"Gatt" > wrote in news:13gnvaq8g7a7e25
@corp.supernews.com:

>
> "Bertie the Bunyip" > wrote in message
> ...
>> "Gatt" > wrote in
>
>>> There goes my Lapin = MX theory. Apologies to Chaud are probably in
>>> order. (I probably apologize?)
>
>> nah, standard sock tactic. If his creation looked too much like himself
>> it'd be too obvious.
>
> Ah, unfortunately I'm not up on sock tactics.
>



Doesn't matter really. all k00ks are basically the same. Whether they're
the same person or not isn't all that relevant. But it's only natural for
them to start feeling a bit lonely and overwhelmed after a while. And when
the worl doesn't deliver some salvation in the form of a friend, then thye
just invent one!


Bertie
>
>
>
>

[Jim Stewart]

Bertie the Bunyip wrote:
> Jim Stewart > wrote in news:4-
> :
>
>> Mxsmanic wrote:
>>> Le Chaud Lapin writes:
>>>
>>>> If you read carefully, the premise of what they are saying is that, if
>>>> you have, for example, a sealed jar with air in it, you are permitted
>>>> to consider the air on the _inside_ of the jar, pushing up on the lid
>>>> as contributing to a force to lift the jar off the ground, but you are
>>>> not allowed to consider the air on the _inside_ of the jar, pushing
>>>> down on the jar un the upper surface of the bottom of the jar.
>>> The atmosphere is not a sealed jar. The source of air pressure in the
>>> atmosphere is gravity, not confinement and kinetic energy.
>> I feel as though I am in the presence of
>> genius.....
>>
>
> Take a tums, it'll get better
>
I'd prefer 2 touch-and-go's and a full
stop. I think that will clear my head.

[Randy Poe]

On Oct 9, 4:25 pm, Bertie the Bunyip > wrote:
> Randy Poe > wrote groups.com:
>
>
>
>
>
> > On Oct 9, 4:08 pm, Le Chaud Lapin > wrote:
> >> Hi All,
>
> >> There is a long discussion ongoing in rec.aviation.piloting about
> what
> >> causes lift on a plane.
>
> > Heh. I know the argument. I think it's broken out here (sci.physics)
> > many times.
>
> > (a) It's the Bernoulli effect due to the shape of the
> > wing cross-section, the way we were all taught as kids.
>
> > (b) No, it's just the angle of attack.
>
> > I'm no expert, but I heard enough in similar arguments here
> > to convince me that the angle-of-attack people are right and
> > the shape of the wing has more to do with controlling
> > turbulence.
[snip]
>
> Well, thanks be to god that that';s been authoritatively setttled.

"Authoritatively"? Can you read? Can you read the
part where I said "I'm no expert" and where I said that
I was convinced by other people?

- Randy

[Randy Poe]

On Oct 9, 4:30 pm, Le Chaud Lapin > wrote:
> On Oct 9, 3:22 pm, Randy Poe > wrote:
>
>
>
> > On Oct 9, 4:08 pm, Le Chaud Lapin > wrote:
>
> > > Hi All,
>
> > > There is a long discussion ongoing in rec.aviation.piloting about what
> > > causes lift on a plane.
>
> > Heh. I know the argument. I think it's broken out here (sci.physics)
> > many times.
>
> > (a) It's the Bernoulli effect due to the shape of the
> > wing cross-section, the way we were all taught as kids.
>
> > (b) No, it's just the angle of attack.
>
> > I'm no expert, but I heard enough in similar arguments here
> > to convince me that the angle-of-attack people are right and
> > the shape of the wing has more to do with controlling
> > turbulence.
>
> > > There are people in the pilot's group, who think that lift on a wing
> > > is analyzed as such:
>
> > > 1. There is air on outside of top of wing that is pushing down, but
> > > reduced because of aerodynamics.
> > > 2. The *inside* of the wing contains air pushing up against the
> > > underside of top of wing .
>
> > Er... that's a new one. OK, I haven't heard this argument
> > then.
>
> > > 3. Let us ignore that the same air inside the wing pushes down on the
> > > overside of bottom part of wing.
> > > 4. The difference in pressure against the underside of the top wing on
> > > the inside of wing and top of wing on outside, is what gives plane
> > > lift.
>
> > You can consider that last just a definition of lift. You
> > won't get lift unless the upward forces are stronger than
> > then downward forces.
>
> > > Note that they ignore the pressure inside the wing that pushes
> > > downward on the wing.
>
> > A wing doesn't need to be hollow to fly.
>
> > > I am trying to convince them that, if there is air on the inside of
> > > the wing, it pushes against all sides of the inside of the wing,
> > > including both top underside and bottom overside, and thereby
> > > nullifying any effect it would have on the wing. Lift is caused by a
> > > difference in pressure between the underside of the bottom of the
> > > wing, and the overside of the top of the wing.
>
> Thanks Randy,
>
> But before we talk about what causes lift on the plane, we should
> clear up the basic physics 1st. Note that what I have described above
> has nothing to do with airplanes really.
>
> If you read carefully, the premise of what they are saying is that, if
> you have, for example, a sealed jar with air in it, you are permitted
> to consider the air on the _inside_ of the jar, pushing up on the lid
> as contributing to a force to lift the jar off the ground, but you are
> not allowed to consider the air on the _inside_ of the jar, pushing
> down on the jar un the upper surface of the bottom of the jar.

Sure, there's air pressure inside a sealed jar, but:

(1) Sealed jars sitting on tables don't spontaneously start
flying, and

(2) Conservation of momentum (for every action there's
an equal and opposite reaction) says that you can't push
up from the inside. You'll create a counter force pushing
down.

(3) Solid things fly in wind also.

- Randy

[Ray Vickson]

On Oct 9, 1:22 pm, Randy Poe > wrote:
> On Oct 9, 4:08 pm, Le Chaud Lapin > wrote:
>
> > Hi All,
>
> > There is a long discussion ongoing in rec.aviation.piloting about what
> > causes lift on a plane.
>
> Heh. I know the argument. I think it's broken out here (sci.physics)
> many times.
>
> (a) It's the Bernoulli effect due to the shape of the
> wing cross-section, the way we were all taught as kids.
>
> (b) No, it's just the angle of attack.

Probably true, in large part anyway. Just consider that aerobatics
pilots can fly their planes upside-down over considerable distances.
If Bernoulli were the sole factor this couldn't happen.

R.G. Vickson

>
> I'm no expert, but I heard enough in similar arguments here
> to convince me that the angle-of-attack people are right and
> the shape of the wing has more to do with controlling
> turbulence.
>
> > There are people in the pilot's group, who think that lift on a wing
> > is analyzed as such:
>
> > 1. There is air on outside of top of wing that is pushing down, but
> > reduced because of aerodynamics.
> > 2. The *inside* of the wing contains air pushing up against the
> > underside of top of wing .
>
> Er... that's a new one. OK, I haven't heard this argument
> then.
>
> > 3. Let us ignore that the same air inside the wing pushes down on the
> > overside of bottom part of wing.
> > 4. The difference in pressure against the underside of the top wing on
> > the inside of wing and top of wing on outside, is what gives plane
> > lift.
>
> You can consider that last just a definition of lift. You
> won't get lift unless the upward forces are stronger than
> then downward forces.
>
> > Note that they ignore the pressure inside the wing that pushes
> > downward on the wing.
>
> A wing doesn't need to be hollow to fly.
>
> > I am trying to convince them that, if there is air on the inside of
> > the wing, it pushes against all sides of the inside of the wing,
> > including both top underside and bottom overside, and thereby
> > nullifying any effect it would have on the wing. Lift is caused by a
> > difference in pressure between the underside of the bottom of the
> > wing, and the overside of the top of the wing.
>
> > I count 8-9 people in the group who are utterly convinced that I am
> > inept at physics, mathematics, etc.
>
> > Note that some of these people have been flying aircraft for years,
> > even decades, while I am still a student pilot.
>
> > Comments from anyone who knows physics welcome.
>
> As I said, I lean toward the angle-of-attack arguments now. Take
> a flat rectangle, tilt it into the wind. The wind blows against the
> front which is also the bottom, not the back/top. So the
> forces are on the bottom.
>
> Why does that translate into lift? I forget the exact arguments
> but from first principles if the effect is to change the direction
> of the incoming air molecules, then by conservation of
> momentum that translates into equal and opposite change
> of momentum of the surface, i.e. pressure with an upward
> component.
>
> - Randy

[Bertie the Bunyip[_19_]]

Jim Stewart > wrote in
:

> Bertie the Bunyip wrote:
>> Jim Stewart > wrote in news:4-
>> :
>>
>>> Mxsmanic wrote:
>>>> Le Chaud Lapin writes:
>>>>
>>>>> If you read carefully, the premise of what they are saying is
>>>>> that, if you have, for example, a sealed jar with air in it, you
>>>>> are permitted to consider the air on the _inside_ of the jar,
>>>>> pushing up on the lid as contributing to a force to lift the jar
>>>>> off the ground, but you are not allowed to consider the air on the
>>>>> _inside_ of the jar, pushing down on the jar un the upper surface
>>>>> of the bottom of the jar.
>>>> The atmosphere is not a sealed jar. The source of air pressure in
>>>> the atmosphere is gravity, not confinement and kinetic energy.
>>> I feel as though I am in the presence of
>>> genius.....
>>>
>>
>> Take a tums, it'll get better
>>
> I'd prefer 2 touch-and-go's and a full
> stop. I think that will clear my head.
>
>


Fair enough.

bertie

[Bertie the Bunyip[_19_]]

Randy Poe > wrote in
ps.com:

> On Oct 9, 4:25 pm, Bertie the Bunyip > wrote:
>> Randy Poe > wrote
>> groups.com:
>>
>>
>>
>>
>>
>> > On Oct 9, 4:08 pm, Le Chaud Lapin > wrote:
>> >> Hi All,
>>
>> >> There is a long discussion ongoing in rec.aviation.piloting about
>> what
>> >> causes lift on a plane.
>>
>> > Heh. I know the argument. I think it's broken out here
>> > (sci.physics) many times.
>>
>> > (a) It's the Bernoulli effect due to the shape of the
>> > wing cross-section, the way we were all taught as kids.
>>
>> > (b) No, it's just the angle of attack.
>>
>> > I'm no expert, but I heard enough in similar arguments here
>> > to convince me that the angle-of-attack people are right and
>> > the shape of the wing has more to do with controlling
>> > turbulence.
> [snip]
>>
>> Well, thanks be to god that that';s been authoritatively setttled.
>
> "Authoritatively"? Can you read? Can you read the
> part where I said "I'm no expert" and where I said that
> I was convinced by other people?


Oow, you ned a sarcasm detector. I can put one up on Ebay for you if you
like.


Bertie

[Bertie the Bunyip[_19_]]

Randy Poe > wrote in
ps.com:

> On Oct 9, 4:30 pm, Le Chaud Lapin > wrote:
>> On Oct 9, 3:22 pm, Randy Poe > wrote:
>>
>>
>>
>> > On Oct 9, 4:08 pm, Le Chaud Lapin > wrote:
>>
>> > > Hi All,
>>
>> > > There is a long discussion ongoing in rec.aviation.piloting about
>> > > what causes lift on a plane.
>>
>> > Heh. I know the argument. I think it's broken out here
>> > (sci.physics) many times.
>>
>> > (a) It's the Bernoulli effect due to the shape of the
>> > wing cross-section, the way we were all taught as kids.
>>
>> > (b) No, it's just the angle of attack.
>>
>> > I'm no expert, but I heard enough in similar arguments here
>> > to convince me that the angle-of-attack people are right and
>> > the shape of the wing has more to do with controlling
>> > turbulence.
>>
>> > > There are people in the pilot's group, who think that lift on a
>> > > wing is analyzed as such:
>>
>> > > 1. There is air on outside of top of wing that is pushing down,
>> > > but reduced because of aerodynamics.
>> > > 2. The *inside* of the wing contains air pushing up against the
>> > > underside of top of wing .
>>
>> > Er... that's a new one. OK, I haven't heard this argument
>> > then.
>>
>> > > 3. Let us ignore that the same air inside the wing pushes down on
>> > > the overside of bottom part of wing.
>> > > 4. The difference in pressure against the underside of the top
>> > > wing on the inside of wing and top of wing on outside, is what
>> > > gives plane lift.
>>
>> > You can consider that last just a definition of lift. You
>> > won't get lift unless the upward forces are stronger than
>> > then downward forces.
>>
>> > > Note that they ignore the pressure inside the wing that pushes
>> > > downward on the wing.
>>
>> > A wing doesn't need to be hollow to fly.
>>
>> > > I am trying to convince them that, if there is air on the inside
>> > > of the wing, it pushes against all sides of the inside of the
>> > > wing, including both top underside and bottom overside, and
>> > > thereby nullifying any effect it would have on the wing. Lift is
>> > > caused by a difference in pressure between the underside of the
>> > > bottom of the wing, and the overside of the top of the wing.
>>
>> Thanks Randy,
>>
>> But before we talk about what causes lift on the plane, we should
>> clear up the basic physics 1st. Note that what I have described
>> above has nothing to do with airplanes really.
>>
>> If you read carefully, the premise of what they are saying is that,
>> if you have, for example, a sealed jar with air in it, you are
>> permitted to consider the air on the _inside_ of the jar, pushing up
>> on the lid as contributing to a force to lift the jar off the ground,
>> but you are not allowed to consider the air on the _inside_ of the
>> jar, pushing down on the jar un the upper surface of the bottom of
>> the jar.
>
> Sure, there's air pressure inside a sealed jar, but:
>
> (1) Sealed jars sitting on tables don't spontaneously start
> flying, and
>
> (2) Conservation of momentum (for every action there's
> an equal and opposite reaction) says that you can't push
> up from the inside. You'll create a counter force pushing
> down.
>
> (3) Solid things fly in wind also.
>

You also need a bull**** detector.

I can do that and the sarcasm detector as a deal for you if you like.


Bertie

[Bertie the Bunyip[_19_]]

Ray Vickson > wrote in news:1191971717.488856.299560
@g4g2000hsf.googlegroups.com:

> On Oct 9, 1:22 pm, Randy Poe > wrote:
>> On Oct 9, 4:08 pm, Le Chaud Lapin > wrote:
>>
>> > Hi All,
>>
>> > There is a long discussion ongoing in rec.aviation.piloting about
what
>> > causes lift on a plane.
>>
>> Heh. I know the argument. I think it's broken out here (sci.physics)
>> many times.
>>
>> (a) It's the Bernoulli effect due to the shape of the
>> wing cross-section, the way we were all taught as kids.
>>
>> (b) No, it's just the angle of attack.
>
> Probably true, in large part anyway. Just consider that aerobatics
> pilots can fly their planes upside-down over considerable distances.
> If Bernoulli were the sole factor this couldn't happen.

Bernoulli still works when you're upside down.


Even with a flat bottomed wing..


Doesn't work so good, BTW, which only strengthens the bernoulli
position, but it does work.



Bertie
>
>

[Le Chaud Lapin]

On Oct 9, 6:15 pm, Randy Poe > wrote:
> (2) Conservation of momentum (for every action there's
> an equal and opposite reaction) says that you can't push
> up from the inside. You'll create a counter force pushing
> down.

Finally, someone speaks reason.

Now all we need to do is see that the jar might as well be a the
volume of a wing, and the same principle applies.

Not possible to have air on inside of wing pushing up against
underside of top of wing without having same said air pushing downward
on overside of bottom part of wing.

-Le Chaud Lapin-

[Le Chaud Lapin]

On Oct 9, 6:15 pm, Ray Vickson > wrote:
> On Oct 9, 1:22 pm, Randy Poe > wrote:
>
> > On Oct 9, 4:08 pm, Le Chaud Lapin > wrote:
>
> > > Hi All,
>
> > > There is a long discussion ongoing in rec.aviation.piloting about what
> > > causes lift on a plane.
>
> > Heh. I know the argument. I think it's broken out here (sci.physics)
> > many times.
>
> > (a) It's the Bernoulli effect due to the shape of the
> > wing cross-section, the way we were all taught as kids.
>
> > (b) No, it's just the angle of attack.
>
> Probably true, in large part anyway. Just consider that aerobatics
> pilots can fly their planes upside-down over considerable distances.
> If Bernoulli were the sole factor this couldn't happen.

Hmm..more reasoning going on in sci.physics.

> R.G. Vickson

I am beginning to think I should have posted my OP in
rec.aviation.piloting to sci.physics.

Very comforting to see people focusing on physics to guide their
arguments.

-Le Chaud Lapin-

[Morgans[_2_]]

"Randy Poe" > wrote

BS and more BS.
***********************
And another sock puppet is born. Sheesh.
--
Jim in NC

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
oups.com:

> On Oct 9, 6:15 pm, Ray Vickson > wrote:
>> On Oct 9, 1:22 pm, Randy Poe > wrote:
>>
>> > On Oct 9, 4:08 pm, Le Chaud Lapin > wrote:
>>
>> > > Hi All,
>>
>> > > There is a long discussion ongoing in rec.aviation.piloting about
>> > > what causes lift on a plane.
>>
>> > Heh. I know the argument. I think it's broken out here
>> > (sci.physics) many times.
>>
>> > (a) It's the Bernoulli effect due to the shape of the
>> > wing cross-section, the way we were all taught as kids.
>>
>> > (b) No, it's just the angle of attack.
>>
>> Probably true, in large part anyway. Just consider that aerobatics
>> pilots can fly their planes upside-down over considerable distances.
>> If Bernoulli were the sole factor this couldn't happen.
>
> Hmm..more reasoning going on in sci.physics.
>
>> R.G. Vickson
>
> I am beginning to think I should have posted my OP in
> rec.aviation.piloting to sci.physics.
>
> Very comforting to see people focusing on physics to guide their
> arguments.
>


Just as long as you **** off there and don't ever fly an airplane.

All of the posts I have seen in reply to yours are either completely
wrong, partially wrong or just off the wallm so you'll be in good
company.


Bertie

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in news:1191974445.830019.13730
@57g2000hsv.googlegroups.com:

> On Oct 9, 6:15 pm, Randy Poe > wrote:
>> (2) Conservation of momentum (for every action there's
>> an equal and opposite reaction) says that you can't push
>> up from the inside. You'll create a counter force pushing
>> down.
>
> Finally, someone speaks reason.
>
> Now all we need to do is see that the jar might as well be a the
> volume of a wing, and the same principle applies.
>
> Not possible to have air on inside of wing pushing up against
> underside of top of wing without having same said air pushing downward
> on overside of bottom part of wing.
>


Good god.

Bertie

[Bertie the Bunyip[_19_]]

"Morgans" > wrote in news:EKUOi.35$KS3.30
@newsfe03.lga:

>
> "Randy Poe" > wrote
>
> BS and more BS.
> ***********************
> And another sock puppet is born. Sheesh.

Nah, he's not a sock. just someone who isn't up to speed on aerodynamics
that Anthony sucked in with a crosspost.


His sock didn't work so he's looking for reinforcements elsewhere.

Told you it would get good!


Bertie

[[email protected]]

On Oct 9, 6:00 pm, Le Chaud Lapin > wrote:
> On Oct 9, 6:15 pm, Randy Poe > wrote:
>
> > (2) Conservation of momentum (for every action there's
> > an equal and opposite reaction) says that you can't push
> > up from the inside. You'll create a counter force pushing
> > down.
>
> Finally, someone speaks reason.
>
> Now all we need to do is see that the jar might as well be a the
> volume of a wing, and the same principle applies.
>
> Not possible to have air on inside of wing pushing up against
> underside of top of wing without having same said air pushing downward
> on overside of bottom part of wing.
>
> -Le Chaud Lapin-

Shoot. And here we used to help the 150 off the ground on a hot
day by pushing up on the ceiling, and if the wind was calm we'd blow
on the windshield, too. Are you saying we were wasting our time?

Seems to me there was ONE guy who talked about the air inside
the wing, but you implied that there were "people" that believed the
air inside had something to do with lift. Not honest about things,
trying to make us all look as ignorant as Mx, or trying to raise your
reputation by finding others to step on. It won't work.

MX and someone else talked about wings with no camber. He was
referring to a sheet of plywood with no curvature and was out to
lunch, as usual, but symmetrical wings have no camber. Camber is the
difference between the chord line and the centerline of the airfoil,
here: http://www.av8n.com/how/htm/airfoils.html#toc56 scroll
down to Figure 3.12. Or this one:
http://www.centennialofflight.gov/essay/Theories_of_Flight/Airfoils/TH13G2.jpg

It would help if these "experts" used the correct terminology so the
rest of us misguided pilots knew what they were talking
about.

Dan

[Le Chaud Lapin]

On Oct 9, 8:18 pm, wrote:
> > Not possible to have air on inside of wing pushing up against
> > underside of top of wing without having same said air pushing downward
> > on overside of bottom part of wing.
>
> > -Le Chaud Lapin-
>
> Shoot. And here we used to help the 150 off the ground on a hot
> day by pushing up on the ceiling, and if the wind was calm we'd blow
> on the windshield, too. Are you saying we were wasting our time?
>
> Seems to me there was ONE guy who talked about the air inside
> the wing, but you implied that there were "people" that believed the
> air inside had something to do with lift. Not honest about things,
> trying to make us all look as ignorant as Mx, or trying to raise your
> reputation by finding others to step on. It won't work.

MX was not the one talking about air inside the wing.

Also, even though you are correct that there was only one person who
was talking about air inside the wing, there were several other posts
made by different people that demonstrated equally questionable
understanding of basic physics.

-Le Chaud Lapin-

[Bertie the Bunyip[_19_]]

wrote in
oups.com:

> On Oct 9, 6:00 pm, Le Chaud Lapin > wrote:
>> On Oct 9, 6:15 pm, Randy Poe > wrote:
>>
>> > (2) Conservation of momentum (for every action there's
>> > an equal and opposite reaction) says that you can't push
>> > up from the inside. You'll create a counter force pushing
>> > down.
>>
>> Finally, someone speaks reason.
>>
>> Now all we need to do is see that the jar might as well be a the
>> volume of a wing, and the same principle applies.
>>
>> Not possible to have air on inside of wing pushing up against
>> underside of top of wing without having same said air pushing
>> downward on overside of bottom part of wing.
>>
>> -Le Chaud Lapin-
>
> Shoot. And here we used to help the 150 off the ground on a hot
> day by pushing up on the ceiling, and if the wind was calm we'd blow
> on the windshield, too. Are you saying we were wasting our time?
>
> Seems to me there was ONE guy who talked about the air inside
> the wing, but you implied that there were "people" that believed the
> air inside had something to do with lift. Not honest about things,
> trying to make us all look as ignorant as Mx, or trying to raise your
> reputation by finding others to step on. It won't work.
>
> MX and someone else talked about wings with no camber. He was
> referring to a sheet of plywood with no curvature and was out to
> lunch, as usual, but symmetrical wings have no camber. Camber is the
> difference between the chord line and the centerline of the airfoil,
> here: http://www.av8n.com/how/htm/airfoils.html#toc56 scroll
> down to Figure 3.12. Or this one:
> http://www.centennialofflight.gov/essay/Theories_of_Flight/Airfoils/TH
1
> 3G2.jpg
>
> It would help if these "experts" used the correct terminology so the
> rest of us misguided pilots knew what they were talking
> about.
>
> Dan
>
>

Symmetrical airfoils have camber because they're not acting
symmetrically when they are in flight.


Bertie

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
ps.com:

> On Oct 9, 8:18 pm, wrote:
>> > Not possible to have air on inside of wing pushing up against
>> > underside of top of wing without having same said air pushing
downward
>> > on overside of bottom part of wing.
>>
>> > -Le Chaud Lapin-
>>
>> Shoot. And here we used to help the 150 off the ground on a hot
>> day by pushing up on the ceiling, and if the wind was calm we'd blow
>> on the windshield, too. Are you saying we were wasting our time?
>>
>> Seems to me there was ONE guy who talked about the air inside
>> the wing, but you implied that there were "people" that believed the
>> air inside had something to do with lift. Not honest about things,
>> trying to make us all look as ignorant as Mx, or trying to raise your
>> reputation by finding others to step on. It won't work.
>
> MX was not the one talking about air inside the wing.
>

Thanks for clearing that up Sockpuppet boi.



> Also, even though you are correct that there was only one person who
> was talking about air inside the wing, there were several other posts
> made by different people that demonstrated equally questionable
> understanding of basic physics.


You have no idea what you're talking about , fjukkwit.


Bertie
>

[CWatters[_2_]]

"Le Chaud Lapin" > wrote in message
ps.com...
> I am trying to convince them that, if there is air on the inside of
> the wing, it pushes against all sides of the inside of the wing,
> including both top underside and bottom overside, and thereby
> nullifying any effect it would have on the wing.

Correct.

If it's sealed the inside of the wing could contain anything at any
pressure. It could be solid metal. Most wings are full of fuel etc etc Makes
no difference to the aerodynamics outside (ignoring weight issues).

[CWatters[_2_]]

"Mxsmanic" > wrote in message
...
> The essential feature of an airfoil is that it twists the flow of air as
it
> passes (or as the airfoil passes through still air, which is equivalent,
and
> that's how it works in airplanes). The air is accelerated downward, and
this
> engenders an equal and opposite force that is lift.

Nope. That wouldn't explain how wing sections for tailless planes work. The
sections for those curve up towards the trailing edge. The leading edge
produces lift but the trailing edge produces a _downward_ force to counter
the pitching moment. Example section...

http://www.desktopaero.com/appliedaero/configuration/images/image13_43.gif

[CWatters[_2_]]

"Mxsmanic" > wrote in message
...
> Gatt writes:
>
> > The day the physics guys were passing out good wing designs, the
aerospace
> > designers were all out drinking beer, which is why every airplane since
the
> > Wright flyer has camber when they could have just used flat plywood.
>
> Some wings do not have camber. Anyway, the purpose of the curve is to
reduce
> drag and increase the stall angle, not to produce lift.

That's simply not correct. Explain why sections for tailless aircraft curve
both ways then.

http://www.desktopaero.com/appliedaero/configuration/images/image13_43.gif

[CWatters[_2_]]

"Mxsmanic" > wrote in message
...
> Le Chaud Lapin writes:
>
> > Even though this (new) thread is not about what causes a wing to lift,
> > I just wanted to say for the record that I agree with this answer,
> > that it is both AoA and curvature of the wing.
>
> It's just AOA.

Nope.

How come most wing sections still produce lift at ZERO degrees AOA?..

Why do slow flying aircraft such as gliders have wing sections with more
camber than fast jets?

[Denny]

Thank the lord that most of the lists I follow are moderated, and
unlike this one do not have this endless baloney going on...

[Bertie the Bunyip[_19_]]

"CWatters" > wrote in
:

>
> "Le Chaud Lapin" > wrote in message
> ps.com...
> > I am trying to convince them that, if there is air on the inside of
>> the wing, it pushes against all sides of the inside of the wing,
>> including both top underside and bottom overside, and thereby
>> nullifying any effect it would have on the wing.
>
> Correct.

Except that he is not trying to convince "them" of anything.

One guy used the air inthe ing thing as an analogy and wannabe troll boi
here is trying to make hay of it.



Bertie

[Bertie the Bunyip[_19_]]

"CWatters" > wrote in
:

>
> "Mxsmanic" > wrote in message
> ...
> > The essential feature of an airfoil is that it twists the flow of
> > air as
> it
>> passes (or as the airfoil passes through still air, which is
>> equivalent,
> and
>> that's how it works in airplanes). The air is accelerated downward,
>> and
> this
>> engenders an equal and opposite force that is lift.
>
> Nope. That wouldn't explain how wing sections for tailless planes
> work. The sections for those curve up towards the trailing edge. The
> leading edge produces lift but the trailing edge produces a _downward_
> force to counter the pitching moment. Example section...
>
> http://www.desktopaero.com/appliedaero/configuration/images/image13_
43.
> gif
>
>
>


Good point.

The porblem with this guy is (and it's just one guy with a handful of
sockpuppets) is that he ses some discrepencies in how bernoulli is
explained and has concluded that it must be incorrect since there is
"disagreement amongst the experts"

A good analogy here would be the eeedjit creationists who grasp at the
straws presented by the minor scuffles occuring within the evolutionary
sciences.


Bertie

[Bertie the Bunyip[_19_]]

"CWatters" > wrote in
:

>
> "Mxsmanic" > wrote in message
> ...
>> Le Chaud Lapin writes:
>>
>> > Even though this (new) thread is not about what causes a wing to
lift,
>> > I just wanted to say for the record that I agree with this answer,
>> > that it is both AoA and curvature of the wing.
>>
>> It's just AOA.
>
> Nope.
>
> How come most wing sections still produce lift at ZERO degrees AOA?..

that is a fact..


>
> Why do slow flying aircraft such as gliders have wing sections with
more
> camber than fast jets?
>
>
>

Ooooh oooh! let me try.

It's because they have to have thicker wings because their spars are
longer and need more stregth,

or it's because the fast ones are made out of meta and are stronger and
their wings don't have to be as thick.

OR

The lift gremlins that hold up gliders don't get as much exercise and
therefore are fatter and need more room.



Or they just fodo it to make 'em look faster. Same reason they sweep the
wings and tail, cuz it makes 'em look kewl!


Bertie

[[email protected]]

Denny, this newsgroup is pretty effectively moderated by Bertie. The
Dudley man does a good job too.

For some of us, even like me mostly trained in the soft sciences, it's
amusing to listen to the wannabe pilots and alleged engineers offer
theories of flight, fluid dynamics, and so on.

It would appear they wouldn't recognize a partial differential
equation if one bit them on the ankle.

Over in the alt.physics group the same class of posters like to
discuss relativity and the message content indicates the relativity
most often at play is inbreeding between family members.

There's a pathology at work with them. It used to be said, with
tongue only partially in cheek, that if you wanted to learn of a
person's character play a round of golf with him (or her). I wish
potential employers would have access to the unsernet postings of
candidates: what a way to screen! Employee turnover would be greatly
reduced. Said differently, if an employer knew of Anthony's postings
and read a little that he wrote, he'd conclude the chances are Anthony
is not likely to be effective in working with others.

Le Chaud presents himself as having a sophmore like mentality -- a
wise fool. Think of a know it all teenager, with little experience,
knowing everything. Those are people who are bad risks as employees,
but whose postings are sometimes fun to read.

And then there are most of us, who go out to our airplane, and
actually fly. That's our reality. Mx needs a gallon's value of avgas
to buy his next meal, and our airplane (it just gets pulled around by
an IO360) uses his weekly food allowance in 90 minutes if we lean it
correctly.

It would seem some dogs like to get kicked.

[Dudley Henriques[_2_]]

Bertie the Bunyip wrote:
> "CWatters" > wrote in
> :
>
>> "Mxsmanic" > wrote in message
>> ...
>>> The essential feature of an airfoil is that it twists the flow of
>>> air as
>> it
>>> passes (or as the airfoil passes through still air, which is
>>> equivalent,
>> and
>>> that's how it works in airplanes). The air is accelerated downward,
>>> and
>> this
>>> engenders an equal and opposite force that is lift.
>> Nope. That wouldn't explain how wing sections for tailless planes
>> work. The sections for those curve up towards the trailing edge. The
>> leading edge produces lift but the trailing edge produces a _downward_
>> force to counter the pitching moment. Example section...
>>
>> http://www.desktopaero.com/appliedaero/configuration/images/image13_
> 43.
>> gif
>>
>>
>>
>
>
> Good point.
>
> The porblem with this guy is (and it's just one guy with a handful of
> sockpuppets) is that he ses some discrepencies in how bernoulli is
> explained and has concluded that it must be incorrect since there is
> "disagreement amongst the experts"
>
> A good analogy here would be the eeedjit creationists who grasp at the
> straws presented by the minor scuffles occuring within the evolutionary
> sciences.
>
>
> Bertie

This is exactly how I see this as well. This character and his puppets
are playing out a conversation with themselves (one person) designed to
capitalize on the few simple misconceptions concerning Bernoulli that
are common knowledge among the professional aviation community and have
been "corrected" years ago.
Unfortunately for this forum, there are still a few old textbooks
hanging around out there reflecting these misconceptions. This, coupled
with the fact that there are individual pilots out here (from the GA
community mostly) who apparently lack the formal physics knowledge to
take on someone whose sole intent is to discredit them by cleverly using
the remaining confusion in the community concerning Bernoulli against them.
The REAL rub in this situation is that the idiot doing this, from what I
have seen in his posting, has very little knowledge HIMSELF about the
lift issue and is totally wrong in critical areas of his argument.
It's an unfortunate situation designed by a person who seems to pleasure
himself by what he's doing.
Personally I wouldn't give this idiot the time of day. His understanding
of Bernoulli is much worse than those with whom he has engaged. Those
who are on to him he avoids, only taking glancing shots at them knowing
he won't be answered directly.
It's a shame really....but what the hell, it's Usenet!!
:-)))

--
Dudley Henriques

[Bertie the Bunyip[_19_]]

wrote in news:1192021318.554579.287500
@o3g2000hsb.googlegroups.com:

> Denny, this newsgroup is pretty effectively moderated by Bertie. The
> Dudley man does a good job too.
>
> For some of us, even like me mostly trained in the soft sciences, it's
> amusing to listen to the wannabe pilots and alleged engineers offer
> theories of flight, fluid dynamics, and so on.
>
> It would appear they wouldn't recognize a partial differential
> equation if one bit them on the ankle.
>
> Over in the alt.physics group the same class of posters like to
> discuss relativity and the message content indicates the relativity
> most often at play is inbreeding between family members.
>
> There's a pathology at work with them. It used to be said, with
> tongue only partially in cheek, that if you wanted to learn of a
> person's character play a round of golf with him (or her). I wish
> potential employers would have access to the unsernet postings of
> candidates: what a way to screen! Employee turnover would be greatly
> reduced. Said differently, if an employer knew of Anthony's postings
> and read a little that he wrote, he'd conclude the chances are Anthony
> is not likely to be effective in working with others.


I don't think that that would be much of a sruprise to them.


>
> Le Chaud presents himself as having a sophmore like mentality -- a
> wise fool. Think of a know it all teenager, with little experience,
> knowing everything. Those are people who are bad risks as employees,
> but whose postings are sometimes fun to read.


He's a sockpuppet. A creation.
>
> And then there are most of us, who go out to our airplane, and
> actually fly. That's our reality. Mx needs a gallon's value of avgas
> to buy his next meal, and our airplane (it just gets pulled around by
> an IO360) uses his weekly food allowance in 90 minutes if we lean it
> correctly.
>
> It would seem some dogs like to get kicked.
>
>

It's what i live for.


Bertie
>
>
>
>

[Bertie the Bunyip[_19_]]

Dudley Henriques > wrote in
:

> Bertie the Bunyip wrote:
>> "CWatters" > wrote in
>> :
>>
>>> "Mxsmanic" > wrote in message
>>> ...
>>>> The essential feature of an airfoil is that it twists the flow of
>>>> air as
>>> it
>>>> passes (or as the airfoil passes through still air, which is
>>>> equivalent,
>>> and
>>>> that's how it works in airplanes). The air is accelerated
>>>> downward, and
>>> this
>>>> engenders an equal and opposite force that is lift.
>>> Nope. That wouldn't explain how wing sections for tailless planes
>>> work. The sections for those curve up towards the trailing edge. The
>>> leading edge produces lift but the trailing edge produces a
>>> _downward_ force to counter the pitching moment. Example section...
>>>
>>> http://www.desktopaero.com/appliedaero/configuration/images/image13_
>> 43.
>>> gif
>>>
>>>
>>>
>>
>>
>> Good point.
>>
>> The porblem with this guy is (and it's just one guy with a handful of
>> sockpuppets) is that he ses some discrepencies in how bernoulli is
>> explained and has concluded that it must be incorrect since there is
>> "disagreement amongst the experts"
>>
>> A good analogy here would be the eeedjit creationists who grasp at
>> the straws presented by the minor scuffles occuring within the
>> evolutionary sciences.
>>
>>
>> Bertie
>
> This is exactly how I see this as well. This character and his puppets
> are playing out a conversation with themselves (one person) designed
> to capitalize on the few simple misconceptions concerning Bernoulli
> that are common knowledge among the professional aviation community
> and have been "corrected" years ago.
> Unfortunately for this forum, there are still a few old textbooks
> hanging around out there reflecting these misconceptions. This,
> coupled with the fact that there are individual pilots out here (from
> the GA community mostly) who apparently lack the formal physics
> knowledge to take on someone whose sole intent is to discredit them by
> cleverly using the remaining confusion in the community concerning
> Bernoulli against them. The REAL rub in this situation is that the
> idiot doing this, from what I have seen in his posting, has very
> little knowledge HIMSELF about the lift issue and is totally wrong in
> critical areas of his argument. It's an unfortunate situation designed
> by a person who seems to pleasure himself by what he's doing.
> Personally I wouldn't give this idiot the time of day. His
> understanding of Bernoulli is much worse than those with whom he has
> engaged. Those who are on to him he avoids, only taking glancing shots
> at them knowing he won't be answered directly.
> It's a shame really....but what the hell, it's Usenet!!
>:-)))

Absolutely. Actually, trolling around the net, it's a bit surprising the
amount of info out there that is so intent on adressing the deficienceis
in the way Bernoulli was described that they appear to be trying to say
that he was wrong. Some of them actually say this flatly.
Bernoulli works and NASA know it.
Their website appears to be disowning him ot the uninitiated, but at the
end of the day, if you need to fly on the edge, there are several colors
you have to paint on he inside of your skull to get your hands to
continuousl select the Alpha required to get th eflight path you want

Bertie

>

[Gig 601XL Builder]

Bertie the Bunyip wrote:

> He's a sockpuppet. A creation.

Who do you think he is a sock puppet for, MX?

[Mxsmanic]

CWatters writes:

> Nope. That wouldn't explain how wing sections for tailless planes work. The
> sections for those curve up towards the trailing edge. The leading edge
> produces lift but the trailing edge produces a _downward_ force to counter
> the pitching moment. Example section...
>
> http://www.desktopaero.com/appliedaero/configuration/images/image13_43.gif

The first thing I saw in this image was "Angle of attack 5.50." Case closed.

[Mxsmanic]

CWatters writes:

> How come most wing sections still produce lift at ZERO degrees AOA?..

They don't do that.

> Why do slow flying aircraft such as gliders have wing sections with more
> camber than fast jets?

Camber becomes more of a liability than an asset at higher speeds.

[Mxsmanic]

Denny writes:

> Thank the lord that most of the lists I follow are moderated, and
> unlike this one do not have this endless baloney going on...

Most moderated lists have nothing going on at all.

[Bertie the Bunyip[_19_]]

Mxsmanic > wrote in
:

> CWatters writes:
>
>> Nope. That wouldn't explain how wing sections for tailless planes
>> work. The sections for those curve up towards the trailing edge. The
>> leading edge produces lift but the trailing edge produces a
>> _downward_ force to counter the pitching moment. Example section...
>>
>> http://www.desktopaero.com/appliedaero/configuration/images/image13_43
>> .gif
>
> The first thing I saw in this image was "Angle of attack 5.50." Case
> closed.
>

Nope


Bertie

[Bertie the Bunyip[_19_]]

Mxsmanic > wrote in
:

> CWatters writes:
>
>> How come most wing sections still produce lift at ZERO degrees AOA?..
>
> They don't do that.
>
>> Why do slow flying aircraft such as gliders have wing sections with more
>> camber than fast jets?
>
> Camber becomes more of a liability than an asset at higher speeds.
>

For reasonswaaaaay beyond you, less is better, but it's still better to
have.

But you've been saying it's not neccesary at all.

So why is it required at low speeds fjukktard?






Or rather, why do you think it is?

(I feel like I've just left a banana skin on the pavement)

[Bertie the Bunyip[_19_]]

"Gig 601XL Builder" <wrDOTgiaconaATsuddenlink.net> wrote in
:

> Bertie the Bunyip wrote:
>
>> He's a sockpuppet. A creation.
>
> Who do you think he is a sock puppet for, MX?
>
>
>

Oh yeah. Classic k00k strategy. He needed someone he could have an
"intelligent" discussion with since we're all too thick to understadn waht
he's talking about.


Bertie

[Bertie the Bunyip[_19_]]

Mxsmanic > wrote in
:

> Denny writes:
>
>> Thank the lord that most of the lists I follow are moderated, and
>> unlike this one do not have this endless baloney going on...
>
> Most moderated lists have nothing going on at all.
>

Much like yourself


Bertie

[[email protected]]

On Oct 10, 7:46 am, Dudley Henriques > wrote:
> Bertie the Bunyip wrote:
> > "CWatters" > wrote in
> :
>
> >> "Mxsmanic" > wrote in message
> ...
> >>> The essential feature of an airfoil is that it twists the flow of
> >>> air as
> >> it
> >>> passes (or as the airfoil passes through still air, which is
> >>> equivalent,
> >> and
> >>> that's how it works in airplanes). The air is accelerated downward,
> >>> and
> >> this
> >>> engenders an equal and opposite force that is lift.
> >> Nope. That wouldn't explain how wing sections for tailless planes
> >> work. The sections for those curve up towards the trailing edge. The
> >> leading edge produces lift but the trailing edge produces a _downward_
> >> force to counter the pitching moment. Example section...
>
> >>http://www.desktopaero.com/appliedaero/configuration/images/image13_
> > 43.
> >> gif
>
> > Good point.
>
> > The porblem with this guy is (and it's just one guy with a handful of
> > sockpuppets) is that he ses some discrepencies in how bernoulli is
> > explained and has concluded that it must be incorrect since there is
> > "disagreement amongst the experts"
>
> > A good analogy here would be the eeedjit creationists who grasp at the
> > straws presented by the minor scuffles occuring within the evolutionary
> > sciences.
>
> > Bertie
>
> This is exactly how I see this as well. This character and his puppets
> are playing out a conversation with themselves (one person) designed to
> capitalize on the few simple misconceptions concerning Bernoulli that
> are common knowledge among the professional aviation community and have
> been "corrected" years ago.
> Unfortunately for this forum, there are still a few old textbooks
> hanging around out there reflecting these misconceptions. This, coupled
> with the fact that there are individual pilots out here (from the GA
> community mostly) who apparently lack the formal physics knowledge to
> take on someone whose sole intent is to discredit them by cleverly using
> the remaining confusion in the community concerning Bernoulli against them.
> The REAL rub in this situation is that the idiot doing this, from what I
> have seen in his posting, has very little knowledge HIMSELF about the
> lift issue and is totally wrong in critical areas of his argument.
> It's an unfortunate situation designed by a person who seems to pleasure
> himself by what he's doing.
> Personally I wouldn't give this idiot the time of day. His understanding
> of Bernoulli is much worse than those with whom he has engaged. Those
> who are on to him he avoids, only taking glancing shots at them knowing
> he won't be answered directly.
> It's a shame really....but what the hell, it's Usenet!!
> :-)))
>
> --
> Dudley Henriques

I haven't minded taking the bait. The process has
pointed out many good websites we can use in instruction, and has
forced a review of some basic principles. Got to find the silver
lining, right?

Dan

[Le Chaud Lapin]

On Oct 10, 10:25 am, wrote:
> > This is exactly how I see this as well. This character and his puppets
> > are playing out a conversation with themselves (one person) designed to
> > capitalize on the few simple misconceptions concerning Bernoulli that
> > are common knowledge among the professional aviation community and have
> > been "corrected" years ago.
> > Unfortunately for this forum, there are still a few old textbooks
> > hanging around out there reflecting these misconceptions. This, coupled
> > with the fact that there are individual pilots out here (from the GA
> > community mostly) who apparently lack the formal physics knowledge to
> > take on someone whose sole intent is to discredit them by cleverly using
> > the remaining confusion in the community concerning Bernoulli against them.
> > The REAL rub in this situation is that the idiot doing this, from what I
> > have seen in his posting, has very little knowledge HIMSELF about the
> > lift issue and is totally wrong in critical areas of his argument.
> > It's an unfortunate situation designed by a person who seems to pleasure
> > himself by what he's doing.
> > Personally I wouldn't give this idiot the time of day. His understanding
> > of Bernoulli is much worse than those with whom he has engaged. Those
> > who are on to him he avoids, only taking glancing shots at them knowing
> > he won't be answered directly.
> > It's a shame really....but what the hell, it's Usenet!!
> > :-)))
>
> > --
> > Dudley Henriques
>
> I haven't minded taking the bait. The process has
> pointed out many good websites we can use in instruction, and has
> forced a review of some basic principles. Got to find the silver
> lining, right?

Right.

Nothing wrong with a little discussion.

-Le Chaud Lapin-

[Uncle Al]

Le Chaud Lapin wrote:
>
> Hi All,
>
> There is a long discussion ongoing in rec.aviation.piloting about what
> causes lift on a plane. You can read from the link below. Please
> note that about 80% of the post are mostly ad hominem attacks and
> should be ignored. There are some small bits of real discussion.
>
> http://groups.google.com/group/rec.aviation.piloting/browse_frm/thread/b85a49e900a0c791/bb11fa289cd7864a#bb11fa289cd7864a
>
> I am an electrical engineer with experience in analag design and
> software, with math and physics background that you would expect of an
> electrical engineer.
>
> There are many points made in the discussion, but I would like to
> focus on one in particular for the sake of progress.
>
> There are people in the pilot's group, who think that lift on a wing
> is analyzed as such:
>
> 1. There is air on outside of top of wing that is pushing down, but
> reduced because of aerodynamics.
> 2. The *inside* of the wing contains air pushing up against the
> underside of top of wing .
> 3. Let us ignore that the same air inside the wing pushes down on the
> overside of bottom part of wing.
> 3. The difference in pressure against the underside of the top wing on
> the inside of wing and top of wing on outside, is what gives plane
> lift.
>
> Note that they ignore the pressure inside the wing that pushes
> downward on the wing.
>
> I am trying to convince them that, if there is air on the inside of
> the wing, it pushes against all sides of the inside of the wing,
> including both top underside and bottom overside, and thereby
> nullifying any effect it would have on the wing. Lift is caused by a
> difference in pressure between the underside of the bottom of the
> wing, and the overside of the top of the wing.
>
> I count 8-9 people in the group who are utterly convinced that I am
> inept at physics, mathematics, etc.
>
> Note that some of these people have been flying aircraft for years,
> even decades, while I am still a student pilot.
>
> Comments from anyone who knows physics welcome.

1) Acrobatic airplane wings are essentially symmetric in
cross-section. They fly equally well rightside-up or inverted. Angle
of attack is important.

2) Bernoulli's law is strictly a 2-D analysis.

3) Dr. Penelope Smith rigorously derived vortex shedding is a major
lift component in 3-D. Don't be Cessna behind a jumbo.

--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/lajos.htm#a2

[Bertie the Bunyip[_19_]]

Uncle Al > wrote in
:

> Le Chaud Lapin wrote:
>>
>> Hi All,
>>
>> There is a long discussion ongoing in rec.aviation.piloting about
>> what causes lift on a plane. You can read from the link below.
>> Please note that about 80% of the post are mostly ad hominem attacks
>> and should be ignored. There are some small bits of real discussion.
>>
>>
http://groups.google.com/group/rec.aviation.piloting/browse_frm/thread
>> /b85a49e900a0c791/bb11fa289cd7864a#bb11fa289cd7864a
>>
>> I am an electrical engineer with experience in analag design and
>> software, with math and physics background that you would expect of
>> an electrical engineer.
>>
>> There are many points made in the discussion, but I would like to
>> focus on one in particular for the sake of progress.
>>
>> There are people in the pilot's group, who think that lift on a wing
>> is analyzed as such:
>>
>> 1. There is air on outside of top of wing that is pushing down, but
>> reduced because of aerodynamics.
>> 2. The *inside* of the wing contains air pushing up against the
>> underside of top of wing .
>> 3. Let us ignore that the same air inside the wing pushes down on the
>> overside of bottom part of wing.
>> 3. The difference in pressure against the underside of the top wing
>> on the inside of wing and top of wing on outside, is what gives plane
>> lift.
>>
>> Note that they ignore the pressure inside the wing that pushes
>> downward on the wing.
>>
>> I am trying to convince them that, if there is air on the inside of
>> the wing, it pushes against all sides of the inside of the wing,
>> including both top underside and bottom overside, and thereby
>> nullifying any effect it would have on the wing. Lift is caused by a
>> difference in pressure between the underside of the bottom of the
>> wing, and the overside of the top of the wing.
>>
>> I count 8-9 people in the group who are utterly convinced that I am
>> inept at physics, mathematics, etc.
>>
>> Note that some of these people have been flying aircraft for years,
>> even decades, while I am still a student pilot.
>>
>> Comments from anyone who knows physics welcome.
>
> 1) Acrobatic airplane wings are essentially symmetric in
> cross-section. They fly equally well rightside-up or inverted. Angle
> of attack is important.
>
> 2) Bernoulli's law is strictly a 2-D analysis.
>
> 3) Dr. Penelope Smith rigorously derived vortex shedding is a major
> lift component in 3-D. Don't be Cessna behind a jumbo.
>

Wow, you are a cut and paste genius Anthony.


Bertie

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
ups.com:

> On Oct 10, 10:25 am, wrote:
>> > This is exactly how I see this as well. This character and his
>> > puppets are playing out a conversation with themselves (one person)
>> > designed to capitalize on the few simple misconceptions concerning
>> > Bernoulli that are common knowledge among the professional aviation
>> > community and have been "corrected" years ago.
>> > Unfortunately for this forum, there are still a few old textbooks
>> > hanging around out there reflecting these misconceptions. This,
>> > coupled with the fact that there are individual pilots out here
>> > (from the GA community mostly) who apparently lack the formal
>> > physics knowledge to take on someone whose sole intent is to
>> > discredit them by cleverly using the remaining confusion in the
>> > community concerning Bernoulli against them. The REAL rub in this
>> > situation is that the idiot doing this, from what I have seen in
>> > his posting, has very little knowledge HIMSELF about the lift issue
>> > and is totally wrong in critical areas of his argument. It's an
>> > unfortunate situation designed by a person who seems to pleasure
>> > himself by what he's doing.
>> > Personally I wouldn't give this idiot the time of day. His
>> > understanding of Bernoulli is much worse than those with whom he
>> > has engaged. Those who are on to him he avoids, only taking
>> > glancing shots at them knowing he won't be answered directly.
>> > It's a shame really....but what the hell, it's Usenet!!
>> > :-)))
>>
>> > --
>> > Dudley Henriques
>>
>> I haven't minded taking the bait. The process has
>> pointed out many good websites we can use in instruction, and has
>> forced a review of some basic principles. Got to find the silver
>> lining, right?
>
> Right.
>
> Nothing wrong with a little discussion.
>


You're not intersted in discussion, fjukkwit


Bertie
>
>

[Bertie the Bunyip[_19_]]

Uncle Al > wrote in
:

> Le Chaud Lapin wrote:
>>
>> Hi All,
>>
>> There is a long discussion ongoing in rec.aviation.piloting about
>> what causes lift on a plane. You can read from the link below.
>> Please note that about 80% of the post are mostly ad hominem attacks
>> and should be ignored. There are some small bits of real discussion.
>>
>>
http://groups.google.com/group/rec.aviation.piloting/browse_frm/thread
>> /b85a49e900a0c791/bb11fa289cd7864a#bb11fa289cd7864a
>>
>> I am an electrical engineer with experience in analag design and
>> software, with math and physics background that you would expect of
>> an electrical engineer.
>>
>> There are many points made in the discussion, but I would like to
>> focus on one in particular for the sake of progress.
>>
>> There are people in the pilot's group, who think that lift on a wing
>> is analyzed as such:
>>
>> 1. There is air on outside of top of wing that is pushing down, but
>> reduced because of aerodynamics.
>> 2. The *inside* of the wing contains air pushing up against the
>> underside of top of wing .
>> 3. Let us ignore that the same air inside the wing pushes down on the
>> overside of bottom part of wing.
>> 3. The difference in pressure against the underside of the top wing
>> on the inside of wing and top of wing on outside, is what gives plane
>> lift.
>>
>> Note that they ignore the pressure inside the wing that pushes
>> downward on the wing.
>>
>> I am trying to convince them that, if there is air on the inside of
>> the wing, it pushes against all sides of the inside of the wing,
>> including both top underside and bottom overside, and thereby
>> nullifying any effect it would have on the wing. Lift is caused by a
>> difference in pressure between the underside of the bottom of the
>> wing, and the overside of the top of the wing.
>>
>> I count 8-9 people in the group who are utterly convinced that I am
>> inept at physics, mathematics, etc.
>>
>> Note that some of these people have been flying aircraft for years,
>> even decades, while I am still a student pilot.
>>
>> Comments from anyone who knows physics welcome.
>
> 1) Acrobatic airplane wings are essentially symmetric in
> cross-section. They fly equally well rightside-up or inverted. Angle
> of attack is important.
>
> 2) Bernoulli's law is strictly a 2-D analysis.
>
> 3) Dr. Penelope Smith rigorously derived vortex shedding is a major
> lift component in 3-D. Don't be Cessna behind a jumbo.
>


Oops, sorry, friendly fire.


Bertie

[JimboCat]

On Oct 10, 7:06 am, Bertie the Bunyip > wrote:
> "CWatters" > wrote :
>
> > "Mxsmanic" > wrote in message
> ...
> > > The essential feature of an airfoil is that it twists the flow of
> > > air as
> > it
> >> passes (or as the airfoil passes through still air, which is
> >> equivalent,
> > and
> >> that's how it works in airplanes). The air is accelerated downward,
> >> and
> > this
> >> engenders an equal and opposite force that is lift.
>
> > Nope. That wouldn't explain how wing sections for tailless planes
> > work. The sections for those curve up towards the trailing edge. The
> > leading edge produces lift but the trailing edge produces a _downward_
> > force to counter the pitching moment. Example section...
>
> >http://www.desktopaero.com/appliedaero/configuration/images/image13_
> 43.
> > gif
>
> Good point.
>
> The porblem with this guy is (and it's just one guy with a handful of
> sockpuppets) is that he ses some discrepencies in how bernoulli is
> explained and has concluded that it must be incorrect since there is
> "disagreement amongst the experts"
>
> A good analogy here would be the eeedjit creationists who grasp at the
> straws presented by the minor scuffles occuring within the evolutionary
> sciences.
>
> Bertie

Obviously, pilots AND the airplanes they fly are just plain too
stoopid to fall.

"Scientists Refute Gravity with New "Intelligent Falling" Theory"
http://www.theonion.com/news/index.php?issue=4133&n=2

Jim Deutch (JimboCat)
--
The Japanese tried coating airplane wings with teflon, but could never
come up with a good nonstick flying plan.

[Bertie the Bunyip[_19_]]

JimboCat > wrote in
ups.com:

> On Oct 10, 7:06 am, Bertie the Bunyip > wrote:
>> "CWatters" > wrote
>> :
>>
>> > "Mxsmanic" > wrote in message
>> ...
>> > > The essential feature of an airfoil is that it twists the flow of
>> > > air as
>> > it
>> >> passes (or as the airfoil passes through still air, which is
>> >> equivalent,
>> > and
>> >> that's how it works in airplanes). The air is accelerated
>> >> downward, and
>> > this
>> >> engenders an equal and opposite force that is lift.
>>
>> > Nope. That wouldn't explain how wing sections for tailless planes
>> > work. The sections for those curve up towards the trailing edge.
>> > The leading edge produces lift but the trailing edge produces a
>> > _downward_ force to counter the pitching moment. Example section...
>>
>> >http://www.desktopaero.com/appliedaero/configuration/images/image13_
>> 43.
>> > gif
>>
>> Good point.
>>
>> The porblem with this guy is (and it's just one guy with a handful of
>> sockpuppets) is that he ses some discrepencies in how bernoulli is
>> explained and has concluded that it must be incorrect since there is
>> "disagreement amongst the experts"
>>
>> A good analogy here would be the eeedjit creationists who grasp at
>> the straws presented by the minor scuffles occuring within the
>> evolutionary sciences.
>>
>> Bertie
>
> Obviously, pilots AND the airplanes they fly are just plain too
> stoopid to fall.
>


This is it.

A bit like the high rise housing in Monty Python that existed only
because he residents had been hypnotised into believeing they did.


Bertie

[JimboCat]

On Oct 9, 4:08 pm, Le Chaud Lapin > wrote:
> Comments from anyone who knows physics welcome.

Hee, hee! You obviously don't know sci.physics!

Jim Deutch (JimboCat)
--
"The world is raining knowledge and most
folks use their soupbowls as rain bonnets."
-- Uncle Al

[Phil]

On Oct 9, 6:15 pm, Ray Vickson > wrote:
> > Heh. I know the argument. I think it's broken out here (sci.physics)
> > many times.
>
> > (a) It's the Bernoulli effect due to the shape of the
> > wing cross-section, the way we were all taught as kids.
>
> > (b) No, it's just the angle of attack.
>
> Probably true, in large part anyway. Just consider that aerobatics
> pilots can fly their planes upside-down over considerable distances.
> If Bernoulli were the sole factor this couldn't happen.
>
> R.G. Vickson

It doesn't have to be either-or. Both Bernoulli and angle of attack
are at work in generating lift. Both the top and bottom surfaces of
the wing contribute. The fact that aerobatic planes can be flown
upside down shows that if you take a normal airfoil and fly it upside
down at the right angle of attack, it will still generate lift. But
unless it has a symmetric airfoil, it will be a lot less efficient
when it is operated upside down. This is because the when it is
upside down, the top surface of the wing is flat rather than curved,
and hence you lose a lot of the lift which this surface generates when
it is rightside up. This is why many aerobatic planes have symmetric
airfoils. A symmetric airfoil works well upside down because it still
has a curved surface on top to help generate lift.

[Jim Logajan]

Uncle Al > wrote:
> 2) Bernoulli's law is strictly a 2-D analysis.

Are you sure? I ask because I know the application of Bernoulli's theorem
to airfoils is typically restricted to 2-D and wondering if that is what
you meant. Otherwise there doesn't appear to be any dimensional assumption
in the theory itself or its derivation. Here's one typical presentation of
Bernoulli's theorem:

"In the steady motion of an inviscid fluid the quantity

p/rho + K

is constant along a streamline, where p is the pressure, rho is the density
and K is the energy per unit mass of fluid."

And the definition of streamline also appears void of dimensional
restriction:

"A line drawn in the fluid so that its tangent at each point is in the
direction of the fluid velocity at that point is called a streamline."

Both quotes from "Theoretical Aerodynamics" by L. M. Milne-Thomson.

So unless I'm mistaken (and I could be) it appears that Bernoulli's
theorem:
1) Applies to compressible or incompressible fluids.
2) Does not necessarily apply to viscous fluid flows.
3) Does not necessarily apply to turbulent flow (it's not "steady motion".)
4) Does not itself define the flow streamlines.
5) Is not restricted to 1 or 2 dimensional analysis.

[Bertie the Bunyip[_19_]]

Phil > wrote in news:1192037923.115677.275220
@o3g2000hsb.googlegroups.com:

> On Oct 9, 6:15 pm, Ray Vickson > wrote:
>> > Heh. I know the argument. I think it's broken out here (sci.physics)
>> > many times.
>>
>> > (a) It's the Bernoulli effect due to the shape of the
>> > wing cross-section, the way we were all taught as kids.
>>
>> > (b) No, it's just the angle of attack.
>>
>> Probably true, in large part anyway. Just consider that aerobatics
>> pilots can fly their planes upside-down over considerable distances.
>> If Bernoulli were the sole factor this couldn't happen.
>>
>> R.G. Vickson
>
> It doesn't have to be either-or. Both Bernoulli and angle of attack
> are at work in generating lift.


That's right, but what's more is that Bernoulli is strengthened by angle of
attack and it's that which provides most of the increase n lift at higher
angles.
Even with a flat bottom wing being flown inverted, most of the lift is
still coming from Bernoulli.



Bertie

[[email protected]]

On Oct 9, 7:33 pm, Bertie the Bunyip > wrote:
> Ray Vickson > wrote in news:1191971717.488856.299560
> @g4g2000hsf.googlegroups.com:
>
>
>
>
>
>
>
> > On Oct 9, 1:22 pm, Randy Poe > wrote:
> >> On Oct 9, 4:08 pm, Le Chaud Lapin > wrote:
>
> >> > Hi All,
>
> >> > There is a long discussion ongoing in rec.aviation.piloting about
> what
> >> > causes lift on a plane.
>
> >> Heh. I know the argument. I think it's broken out here (sci.physics)
> >> many times.
>
> >> (a) It's the Bernoulli effect due to the shape of the
> >> wing cross-section, the way we were all taught as kids.
>
> >> (b) No, it's just the angle of attack.
>
> > Probably true, in large part anyway. Just consider that aerobatics
> > pilots can fly their planes upside-down over considerable distances.
> > If Bernoulli were the sole factor this couldn't happen.
>
> Bernoulli still works when you're upside down.
>
> Even with a flat bottomed wing..
>
> Doesn't work so good, BTW, which only strengthens the bernoulli
> position, but it does work.

But the Bernoulli position works best with helicopters.
That's why they were invented for winged weirdos,
who know kust about nothing about Bernoulli.
Other than he once made a principle for
Newton idiots.
c

>
> Bertie
>
>
>
> - Hide quoted text -
>
> - Show quoted text -- Hide quoted text -
>
> - Show quoted text -

[Bertie the Bunyip[_19_]]

" > wrote in
ups.com:

> On Oct 9, 7:33 pm, Bertie the Bunyip > wrote:
>> Ray Vickson > wrote in news:1191971717.488856.299560
>> @g4g2000hsf.googlegroups.com:
>>
>>
>>
>>
>>
>>
>>
>> > On Oct 9, 1:22 pm, Randy Poe > wrote:
>> >> On Oct 9, 4:08 pm, Le Chaud Lapin > wrote:
>>
>> >> > Hi All,
>>
>> >> > There is a long discussion ongoing in rec.aviation.piloting
about
>> what
>> >> > causes lift on a plane.
>>
>> >> Heh. I know the argument. I think it's broken out here
(sci.physics)
>> >> many times.
>>
>> >> (a) It's the Bernoulli effect due to the shape of the
>> >> wing cross-section, the way we were all taught as kids.
>>
>> >> (b) No, it's just the angle of attack.
>>
>> > Probably true, in large part anyway. Just consider that aerobatics
>> > pilots can fly their planes upside-down over considerable
distances.
>> > If Bernoulli were the sole factor this couldn't happen.
>>
>> Bernoulli still works when you're upside down.
>>
>> Even with a flat bottomed wing..
>>
>> Doesn't work so good, BTW, which only strengthens the bernoulli
>> position, but it does work.
>
> But the Bernoulli position works best with helicopters.
> That's why they were invented for winged weirdos,
> who know kust about nothing about Bernoulli.
> Other than he once made a principle for
> Newton idiots.
> c
>


I see

Bertie>

[CWatters[_2_]]

"Mxsmanic" > wrote in message
...
> CWatters writes:
>
> > Nope. That wouldn't explain how wing sections for tailless planes work.
The
> > sections for those curve up towards the trailing edge. The leading edge
> > produces lift but the trailing edge produces a _downward_ force to
counter
> > the pitching moment. Example section...
> >
> >
http://www.desktopaero.com/appliedaero/configuration/images/image13_43.gif
>
> The first thing I saw in this image was "Angle of attack 5.50." Case
closed.

So what's that got to do with anything. You can simulate the performance of
a section at any AOA you like. Try it yourself at AOA = 0 degrees. You might
be surprised.

[CWatters[_2_]]

"Mxsmanic" > wrote in message
...
> CWatters writes:
>
> > How come most wing sections still produce lift at ZERO degrees AOA?..
>
> They don't do that.

Yes they do. Almost any wing that has camber generates lift at zero degrees
AOA. The more camber a wing has the more pronounced this effect is

The very first polar plot google finds shows this...

http://www.mh-aerotools.de/airfoils/images/hdi_pol3.gif

Notice how Cl is about 0.45 when the AOA is zero.

[CWatters[_2_]]

"Mxsmanic" > wrote in message
...
> Le Chaud Lapin writes:
>
> > Even though this (new) thread is not about what causes a wing to lift,
> > I just wanted to say for the record that I agree with this answer,
> > that it is both AoA and curvature of the wing.
>
> It's just AOA.

Ok so explain how we measure the AOA of the ball in this video...

http://uk.youtube.com/watch?v=Vg-_nnYm7mw&mode=related&search=

[Gig 601XL Builder]

CWatters wrote:
> "Mxsmanic" > wrote in message
> ...
>> Le Chaud Lapin writes:
>>
>>> Even though this (new) thread is not about what causes a wing to
>>> lift, I just wanted to say for the record that I agree with this
>>> answer, that it is both AoA and curvature of the wing.
>>
>> It's just AOA.
>
> Ok so explain how we measure the AOA of the ball in this video...
>
> http://uk.youtube.com/watch?v=Vg-_nnYm7mw&mode=related&search=

And if that one doesn't do it for you here's another.

http://uk.youtube.com/watch?v=5YHqCkCJbWQ&NR=1

[ABLE_1[_2_]]

http://uk.youtube.com/watch?v=KCcZyW-6-5o

Enjoy!!!





>>
>> Ok so explain how we measure the AOA of the ball in this video...
>>
>> http://uk.youtube.com/watch?v=Vg-_nnYm7mw&mode=related&search=
>
> And if that one doesn't do it for you here's another.
>
> http://uk.youtube.com/watch?v=5YHqCkCJbWQ&NR=1
>
>
>

[Jim Logajan]

"ABLE_1" > wrote:
> http://uk.youtube.com/watch?v=KCcZyW-6-5o
>
> Enjoy!!!

Here's something that flies which doesn't rely on Bernoulli's theorem:

http://uk.youtube.com/watch?v=1T2gg4zpyuo

Enjoy!

(By my estimate, at Akron's max speed of 72 knots it would travel its own
length in about 6.5 seconds. That's roughly in range of how fast its shadow
appears to cross points on the clouds, so IMHO the Youtube poster who said
it appeared to be traveling 500 mph is wrong.

Anyway, it's nice to imagine the 8 Maybach engines sounding about like that
at full throttle.)

[Jim Logajan]

Jim Logajan > wrote:
> Here's something that flies which doesn't rely on Bernoulli's theorem:
>
> http://uk.youtube.com/watch?v=1T2gg4zpyuo

Correction - should have used past tense.

[george]

On Oct 11, 10:10 am, Nomen Nescio > wrote:

> Just a "heads up".
> "Mxsmanic" and "Le Chaud Lapin" are the same person.
>
> And they're both idiots. :)

You rate him/them far to highly

[Dudley Henriques[_2_]]

wrote:
> On Oct 10, 7:46 am, Dudley Henriques > wrote:
>> Bertie the Bunyip wrote:
>>> "CWatters" > wrote in
>>> :
>>>> "Mxsmanic" > wrote in message
>>>> ...
>>>>> The essential feature of an airfoil is that it twists the flow of
>>>>> air as
>>>> it
>>>>> passes (or as the airfoil passes through still air, which is
>>>>> equivalent,
>>>> and
>>>>> that's how it works in airplanes). The air is accelerated downward,
>>>>> and
>>>> this
>>>>> engenders an equal and opposite force that is lift.
>>>> Nope. That wouldn't explain how wing sections for tailless planes
>>>> work. The sections for those curve up towards the trailing edge. The
>>>> leading edge produces lift but the trailing edge produces a _downward_
>>>> force to counter the pitching moment. Example section...
>>>> http://www.desktopaero.com/appliedaero/configuration/images/image13_
>>> 43.
>>>> gif
>>> Good point.
>>> The porblem with this guy is (and it's just one guy with a handful of
>>> sockpuppets) is that he ses some discrepencies in how bernoulli is
>>> explained and has concluded that it must be incorrect since there is
>>> "disagreement amongst the experts"
>>> A good analogy here would be the eeedjit creationists who grasp at the
>>> straws presented by the minor scuffles occuring within the evolutionary
>>> sciences.
>>> Bertie
>> This is exactly how I see this as well. This character and his puppets
>> are playing out a conversation with themselves (one person) designed to
>> capitalize on the few simple misconceptions concerning Bernoulli that
>> are common knowledge among the professional aviation community and have
>> been "corrected" years ago.
>> Unfortunately for this forum, there are still a few old textbooks
>> hanging around out there reflecting these misconceptions. This, coupled
>> with the fact that there are individual pilots out here (from the GA
>> community mostly) who apparently lack the formal physics knowledge to
>> take on someone whose sole intent is to discredit them by cleverly using
>> the remaining confusion in the community concerning Bernoulli against them.
>> The REAL rub in this situation is that the idiot doing this, from what I
>> have seen in his posting, has very little knowledge HIMSELF about the
>> lift issue and is totally wrong in critical areas of his argument.
>> It's an unfortunate situation designed by a person who seems to pleasure
>> himself by what he's doing.
>> Personally I wouldn't give this idiot the time of day. His understanding
>> of Bernoulli is much worse than those with whom he has engaged. Those
>> who are on to him he avoids, only taking glancing shots at them knowing
>> he won't be answered directly.
>> It's a shame really....but what the hell, it's Usenet!!
>> :-)))
>>
>> --
>> Dudley Henriques
>
> I haven't minded taking the bait. The process has
> pointed out many good websites we can use in instruction, and has
> forced a review of some basic principles. Got to find the silver
> lining, right?
>
> Dan
>

A good visual tool I've used as an example through the years is a
cylinder. Stationary with no circulation on a cylinder in a freestream
you have a 0 AOA stagnation point leading and trailing edge with equal
streamlines. No Bernoulli; no Newton. no lift.
Now spin the cylinder (same as increasing AOA on an airfoil...simple
Magnus effect)and you lower both stagnation points front and back as
circulation becomes a factor. You now have Bernoulli top and bottom and
up wash and down wash created simultaneously on the cylinder; you also
now have lift!
An airfoil works the same way as it rotates through angle of attack.
Actually, a barn door will work the same way as well :-))

There are differences of course in how symmetrical and cambered airfoils
work as far as the center of pressure and moment arms work on the wings
vs angle of attack and zero lift but basically using a cylinder then
rotating it demonstrates simply that if lift is being created, both
Bernoulli and Newton are existing at the same time and either can be
used to explain how a net lift force is created.
The rest of it is all peripheral data and usually confuses both people
as well as the airport cat as they get lost in what causes what how what
causes lift.

--
Dudley Henriques

[Morgans[_2_]]

> wrote
> Denny, this newsgroup is pretty effectively moderated by Bertie. The
> Dudley man does a good job too.
\
Sadly, it has deteriorated to the current state.

People used to have real discussions about flying, instead of the constant
discord.

I long for the return of discussions where an idiot does not pervert every
thread, and all of the people that left, return.
--
Jim in NC

[CWatters[_2_]]

"Jim Logajan" > wrote in message
.. .
> "ABLE_1" > wrote:
> > http://uk.youtube.com/watch?v=KCcZyW-6-5o
> >
> > Enjoy!!!
>
> Here's something that flies which doesn't rely on Bernoulli's theorem:
>
> http://uk.youtube.com/watch?v=1T2gg4zpyuo
>

....except when it's trying to climb fast, or turn. :-)

[CWatters[_2_]]

"CWatters" > wrote in message
...
>
> "Jim Logajan" > wrote in message
> .. .
> > "ABLE_1" > wrote:
> > > http://uk.youtube.com/watch?v=KCcZyW-6-5o
> > >
> > > Enjoy!!!
> >
> > Here's something that flies which doesn't rely on Bernoulli's theorem:
> >
> > http://uk.youtube.com/watch?v=1T2gg4zpyuo
> >
>
> ...except when it's trying to climb fast, or turn. :-)
>
>

Oh and for the props.

[mike regish]

I think that the shape of the wing simply allows for a greater range of
angles of attack. A sheet of plywood would provide lift, but only at a very
precise and small angle of attack. The airfoil shape allows the wing to
provide lift through a much larger range of angles of attack.

JMO.

mike
"Gatt" > wrote in message
...
>
> "Bertie the Bunyip" > wrote in message
> ...
>> Mxsmanic > wrote in
>> :
>>
>>> Le Chaud Lapin writes:
>>>
>>>> Even though this (new) thread is not about what causes a wing to lift,
>>>> I just wanted to say for the record that I agree with this answer,
>>>> that it is both AoA and curvature of the wing.
>>>
>>> It's just AOA.
>>>
>> Nope.
>
> There goes my Lapin = MX theory. Apologies to Chaud are probably in
> order. (I probably apologize?)
>
> -c
>

[Uncle Al]

Jim Logajan wrote:
>
> Uncle Al > wrote:
> > 2) Bernoulli's law is strictly a 2-D analysis.
>
> Are you sure? I ask because I know the application of Bernoulli's theorem
> to airfoils is typically restricted to 2-D and wondering if that is what
> you meant. Otherwise there doesn't appear to be any dimensional assumption
> in the theory itself or its derivation. Here's one typical presentation of
> Bernoulli's theorem:
>
> "In the steady motion of an inviscid fluid the quantity
>
> p/rho + K
>
> is constant along a streamline, where p is the pressure, rho is the density
> and K is the energy per unit mass of fluid."
>
> And the definition of streamline also appears void of dimensional
> restriction:
>
> "A line drawn in the fluid so that its tangent at each point is in the
> direction of the fluid velocity at that point is called a streamline."
>
> Both quotes from "Theoretical Aerodynamics" by L. M. Milne-Thomson.
>
> So unless I'm mistaken (and I could be) it appears that Bernoulli's
> theorem:
> 1) Applies to compressible or incompressible fluids.
> 2) Does not necessarily apply to viscous fluid flows.
> 3) Does not necessarily apply to turbulent flow (it's not "steady motion".)
> 4) Does not itself define the flow streamlines.
> 5) Is not restricted to 1 or 2 dimensional analysis.

3-D wings are more than Bernoulli's law. If they weren't they
wouldn't vastly benefit from shaped distal winglets to control vortex
shedding. Adding small drag surfaces at the wingtips normal to the
wings' surfaces does not have beneficial - much less hugely beneficial
- effects in 2-D analysis. In the real world airlines madly scrambled
to add winglets to improve fuel economy.

Look at the ratio of surface areas, wing and its winglet. The real
world benefits are wholly disproportional to area ratio. It is a
matter of leverage. A tiny tweaking of vortices rolling off distal
wing ends creates major energy control.

--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/lajos.htm#a2

[Gatt]

"Le Chaud Lapin" > wrote in message
ups.com...

>> I haven't minded taking the bait. The process has pointed
>> out many good websites we can use in instruction, and has
>> forced a review of some basic principles. Got to find the silver lining,
>> right?
>
> Right.
>
> Nothing wrong with a little discussion.

Why did you post "True Understanding Or Monkey Mode" about the same thing in
rec.aviation.piloting. Are you accusing pilots of being monkeys?

If so, do you expect to be treated with some sort of respect by people who
actually read aviation textbooks and fly planes? By the way, how's that
EB-6 training going?

-c

[Gatt]

"Gig 601XL Builder" <wrDOTgiaconaATsuddenlink.net> wrote in message
...

>> He's a sockpuppet. A creation.
>
> Who do you think he is a sock puppet for, MX?

Yes. His content, character and tone are strikingly similar to what MX was
posting around the time everybody was at Oshkosh. Lots of nonsense about
AOA, camber, downwash, etc.

-c

[Gatt]

"Morgans" > wrote in message
...

> Sadly, it has deteriorated to the current state.
>
> People used to have real discussions about flying, instead of the constant
> discord.

Actually, I'm enjoying the tangental stuff that people like Dudley are
posting. Actual physics. Even if somebody appears to be trolling, it's
useful to hear experts articulate what we all pretty much know, plus I've
gotten at least two useful book recommendations out of the thread.

Maybe the OP is just a foil for the rest of us to talk about aerodynamics.
Works for me.

-c

[Le Chaud Lapin]

On Oct 11, 10:23 am, "Gatt" > wrote:
> "Le Chaud Lapin" > wrote in
> > Nothing wrong with a little discussion.
>
> Why did you post "True Understanding Or Monkey Mode" about the same thing in
> rec.aviation.piloting. Are you accusing pilots of being monkeys?

No. If you read the posts, I was complaining about both the students
and the pilots, mostly the students.

As I mentioned, I was sitting in lobby of flight school one day,
toward the end of ground school class, and there were 7-8 students
cramming for their final and to take FAA KT. We were talking about
what we think we should know, and one of the students hintet that
understanding was not really important. And said, "Well, I'm going to
take the final, and pass hopefully, but I get the feeling that this
class was too fast, and frankly, the only reason I have passed so far
is that I've been cramming." They all laughed and said, "Yeah, and?.
Look, if you want to pass the FAA KT, forget about that book
(Jeppesen's private) pilot. Go to Sporty's. They have a bunch of
questions. Plus you should get as many real FAA test questions.
That's all you need to do, to be able to anticipate what they are
going to ask you." I asked, "Don't you really want to know..or?" They
said, "No, after the exam, it doesn't matter. Not like I'm going for
ATP or anything." I looked around the room and there was general
agreement, although there was one student who understood because he'd
been into flying from very early age (like 10). One of students
announced that this was his 4th time around, and this time he was
focused...but it was apparent that by, "focused", he meant passing the
exam.

> If so, do you expect to be treated with some sort of respect by people who
> actually read aviation textbooks and fly planes? By the way, how's that
> EB-6 training going?

Just trying to get to the bottom of what expectations there should
be. I've taught at professional level, and I can tell you that, while
I did not expect my students to know everything we've covered, when
they took an exam and wrote down an answer, it was due to thinking
through the problem, not memorization.

As for the EB-6, no problem. I studied it in advance before the ground
school class. I knew how to covert between the various types of
altitudes, etc...but I did not really know what density altitude.

I think these topics would be easier to remember if they were thought
through. For example, remember 29.92 on barometer is good, but would
be better if people had some idea of where 29.92 comes from. I asked
around the room, and no one knew, not even the CFI.

-Le Chaud Lapin-

[Le Chaud Lapin]

On Oct 11, 12:15 am, "Morgans" > wrote:
> > wrote> Denny, this newsgroup is pretty effectively moderated by Bertie. The
> > Dudley man does a good job too.
>
> \
> Sadly, it has deteriorated to the current state.
>
> People used to have real discussions about flying, instead of the constant
> discord.
>
> I long for the return of discussions where an idiot does not pervert every
> thread, and all of the people that left, return.
> --
> Jim in NC

Hmm...I re-read my original 3 posts, two to rec.aviation.piloting, and
I do not see much perversion in them. I have recopied the most
controversial post for benefit of people in sci.physics.

If there is any perversion, it mostly came from susquent insults from
people who were upset by the idea that I might be reevaluating
backwash.

-Le Chaud Lapin-

Orginal Post Entitled "Backwash Causes Lift?" in
rec.aviation.piloting:

On Oct 2, 8:57 pm, Le Chaud Lapin > wrote:
> Hi,
>
> Student pilot here, self-teaching using the Jeppensen Private Pilot
> Kit after taking ground school. :D
>
> I read in the book that combustion "creates" energy, which is
> technically not true, but I decided to ignore it since the pictures
> are sooo pretty.
>
> Now, in Chapter 3, section about airfoils, it actually says:
>
> "In addition to the lowered pressure, a downward-backward flow of air
> also is generated from the top surface of the wing. The reaction to
> this downwash results in an upward force on the wing which demnstrates
> Newtons' third law of motion. This action/reaction principle also is
> apparent as the airstream strikes the lwoer surface of the wing when
> inclinded at a small angle (the angle of attack) to its direction of
> motion. The air is forced downward and therefore causes an upward
> reaction resulting in positive lift."
>
> IMHO, the latter part of this paragraph is correct, but the former
> part is wrong.
>
> Obviously, any air above the wing can only result in a force downward
> on top of the wing. The only force causing the plane to want to move
> upward comes from beneath the wing. The effect of any air above the
> wing is to cause rarefication above the wing, resulting in lower
> pressure, thereby giving the 14.7lbs/in^2 (plus) to do its work. That
> "reaction" coming from downward movement of air seems just plain silly
> to me.
>
> I am also inclined to take issue with the explanations of Bernouilli's
> Principle which I see often in the literature, but that's a different
> subject. [Note, I don't doubt Bernouilli's Principle, I just think
> there is more to it than the way it is being described in context of
> flying.]
>
> -Le Chaud Lapin-

[BDS[_2_]]

"Le Chaud Lapin" > wrote

> As I mentioned, I was sitting in lobby of flight school one day,
> toward the end of ground school class, and there were 7-8 students
> cramming for their final and to take FAA KT. We were talking about
> what we think we should know, and one of the students hintet that
> understanding was not really important.

Anyone who thinks that will be in for a surprise when they take the oral
portion of the practical test, if they get that far. Good instructors will
be checking their students' comprehension of the required knowledge on a
continuing basis as flight lessons progress. I doubt that you would get a
signoff for your practical from an instructor who suspected that you were
only at the rote learning level.

> I think these topics would be easier to remember if they were thought
> through. For example, remember 29.92 on barometer is good, but would
> be better if people had some idea of where 29.92 comes from. I asked
> around the room, and no one knew, not even the CFI.

If true, that's one end of the spectrum I suppose, and one isolated
instance.

BDS

[Mxsmanic]

Le Chaud Lapin writes:

> For example, remember 29.92 on barometer is good, but would
> be better if people had some idea of where 29.92 comes from. I asked
> around the room, and no one knew, not even the CFI.

Seriously?

[Jim Logajan]

"CWatters" > wrote:
> "CWatters" > wrote in message
> ...
>>
>> "Jim Logajan" > wrote in message
>> .. .
>> > "ABLE_1" > wrote:
>> > > http://uk.youtube.com/watch?v=KCcZyW-6-5o
>> > >
>> > > Enjoy!!!
>> >
>> > Here's something that flies which doesn't rely on Bernoulli's theorem:
>> >
>> > http://uk.youtube.com/watch?v=1T2gg4zpyuo
>>
>> ...except when it's trying to climb fast, or turn. :-)
>
> Oh and for the props.

Minor details! ;-)

(I also know that rigid airships typically flew deliberately "heavy" and
relied a bit on dynamic lift.)

[Le Chaud Lapin]

On Oct 11, 12:31 pm, "BDS" > wrote:
> "Le Chaud Lapin" > wrote
>
> > As I mentioned, I was sitting in lobby of flight school one day,
> > toward the end of ground school class, and there were 7-8 students
> > cramming for their final and to take FAA KT. We were talking about
> > what we think we should know, and one of the students hintet that
> > understanding was not really important.
>
> Anyone who thinks that will be in for a surprise when they take the oral
> portion of the practical test, if they get that far. Good instructors will
> be checking their students' comprehension of the required knowledge on a
> continuing basis as flight lessons progress. I doubt that you would get a
> signoff for your practical from an instructor who suspected that you were
> only at the rote learning level.

That brings me to next question:

How difficult is the oral part?. Time is limited so obviously they
cannot ask every thing. Is it possible for a student to slip by on the
oral portion and just do well on practical and still pass?

Also, can FAA examiners act as instructors simultaneously or is there
a rule forbidding it?

-Le Chaud Lapin-

[B A R R Y[_2_]]

Le Chaud Lapin wrote:
> >
> How difficult is the oral part?. Time is limited so obviously they
> cannot ask every thing.

No, but displaying weakness on a subject matter will usually draw more
questions, or requests for clarification, on that subject. In my
experience, the examiner will arrive with a plan for each section of the
exam, so that the important stuff will be covered.

For stuff that isn't often used, ex:// FAR minute details, you can ask
to look it up. BS'ing is usually a bad plan if you really don't know
something.

The actual time period is at the discretion of the examiner. There is
no egg timer running during the test.

Also, the oral portion doesn't end when you get into the airplane for
the practical portion. The oral can theoretically continue right up to
when your temporary certificate is issued.

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
ps.com:

> On Oct 11, 10:23 am, "Gatt" > wrote:
>> "Le Chaud Lapin" > wrote in
>> > Nothing wrong with a little discussion.
>>
>> Why did you post "True Understanding Or Monkey Mode" about the same
>> thing in rec.aviation.piloting. Are you accusing pilots of being
>> monkeys?
>
> No. If you read the posts, I was complaining about both the students
> and the pilots, mostly the students.
>
> As I mentioned, I was sitting in lobby of flight school one day,
> toward the end of ground school class, and there were 7-8 students
> cramming for their final and to take FAA KT. We were talking about
> what we think we should know, and one of the students hintet that
> understanding was not really important. And said, "Well, I'm going to
> take the final, and pass hopefully, but I get the feeling that this
> class was too fast, and frankly, the only reason I have passed so far
> is that I've been cramming." They all laughed and said, "Yeah, and?.
> Look, if you want to pass the FAA KT, forget about that book
> (Jeppesen's private) pilot. Go to Sporty's. They have a bunch of
> questions. Plus you should get as many real FAA test questions.
> That's all you need to do, to be able to anticipate what they are
> going to ask you." I asked, "Don't you really want to know..or?" They
> said, "No, after the exam, it doesn't matter. Not like I'm going for
> ATP or anything." I looked around the room and there was general
> agreement, although there was one student who understood because he'd
> been into flying from very early age (like 10). One of students
> announced that this was his 4th time around, and this time he was
> focused...but it was apparent that by, "focused", he meant passing the
> exam.
>
>> If so, do you expect to be treated with some sort of respect by
>> people who actually read aviation textbooks and fly planes? By the
>> way, how's that EB-6 training going?
>
> Just trying to get to the bottom of what expectations there should
> be. I've taught at professional level, and I can tell you that, while
> I did not expect my students to know everything we've covered, when
> they took an exam and wrote down an answer, it was due to thinking
> through the problem, not memorization.
>
> As for the EB-6, no problem. I studied it in advance before the ground
> school class. I knew how to covert between the various types of
> altitudes, etc...but I did not really know what density altitude.
>
> I think these topics would be easier to remember if they were thought
> through. For example, remember 29.92 on barometer is good, but would
> be better if people had some idea of where 29.92 comes from. I asked
> around the room, and no one knew, not even the CFI.


I do, send me 200$ and I'll tell you

I still take paypal.


Bertie
>
>

[Bertie the Bunyip[_19_]]

Mxsmanic > wrote in
:

> Le Chaud Lapin writes:
>
>> For example, remember 29.92 on barometer is good, but would
>> be better if people had some idea of where 29.92 comes from. I asked
>> around the room, and no one knew, not even the CFI.
>
> Seriously?
>



Bwawhahwhahwhahwhahwhahwhahwhhahwhahwhahwhahwhahwh ha!

God you're pathetic sockpuppetboi



Bertie

[Gatt]

"Le Chaud Lapin" > wrote in message
ps.com...

>> Why did you post "True Understanding Or Monkey Mode" about the same thing
>> in
>> rec.aviation.piloting. Are you accusing pilots of being monkeys?
>
> No. If you read the posts, I was complaining about both the students
> and the pilots, mostly the students.

You ARE a student. You, IIRC, where discussing the logarithmic flaws of the
"EB-6" if I remember correctly.

> As for the EB-6, no problem. I studied it in advance before the ground
> school class.

I can tell. But, like I said in r.a.s, I made it clear through the
commercial license without ever once using an EB-6.

-c

[Gatt]

"Le Chaud Lapin" > wrote in message
oups.com...

> How difficult is the oral part?.

It's easy if you know the material. It's going to be related to practical
things like airspace, regulations, medical and equipment requirements, cross
country planning, etc.

>Time is limited so obviously they cannot ask every thing. Is it possible
>for a student to slip by on the
> oral portion and just do well on practical and still pass?

It's possible, but if you can't do well on the oral portion the practical
might really kick your ass, particularly in the flight planning phase.

-c

[Le Chaud Lapin]

On Oct 11, 12:38 pm, Mxsmanic > wrote:
> Le Chaud Lapin writes:
> > For example, remember 29.92 on barometer is good, but would
> > be better if people had some idea of where 29.92 comes from. I asked
> > around the room, and no one knew, not even the CFI.
>
> Seriously?

Yes, seriously. The CFI was a very likeable person, a bit young,
maybe mid 20's. I am sure he is competent as a pilot. I would not
hesitate to fly with him. But personally, I have a real hard time
being told to plug in numbers with no real understanding why. My
ability to retain quickly drops to zero doing that.

-Le Chaud Lapin-

[Le Chaud Lapin]

On Oct 11, 1:27 pm, "Gatt" > wrote:
> "Le Chaud Lapin" > wrote in glegroups.com...
>
> >> Why did you post "True Understanding Or Monkey Mode" about the same thing
> >> in
> >> rec.aviation.piloting. Are you accusing pilots of being monkeys?
>
> > No. If you read the posts, I was complaining about both the students
> > and the pilots, mostly the students.
>
> You ARE a student. You, IIRC, where discussing the logarithmic flaws of the
> "EB-6" if I remember correctly.

Nope. I mentioned that I had followed the yellow and blue book page
by page, and after that, I want to look at the EB-6 a little more, to
try to understand if there were any relationships on the scales to
help with memory. I asked if those relationships were linear, and one
or two other people said that it was logarithm, and another person
said that it is effectively a slide rule. I did not say whether it
was linear or logarithmic, except for the temperature scale.

> > As for the EB-6, no problem. I studied it in advance before the ground
> > school class.
>
> I can tell. But, like I said in r.a.s, I made it clear through the
> commercial license without ever once using an EB-6.

So, my question might have been, which B A R R Y seems to have
answered, is...

"Given all the things in the Jeppesen $200 kit, are we expected to
know those things or not?"

I had been assuming that the FAA actually wants people to know. I had
decided for myself not to take the KT yet even though I could probably
pass (barely) right now.

-Le Chaud Lapin-

[Le Chaud Lapin]

On Oct 11, 1:31 pm, "Gatt" > wrote:
> "Le Chaud Lapin" > wrote in ooglegroups.com...
>
> > How difficult is the oral part?.
>
> It's easy if you know the material. It's going to be related to practical
> things like airspace, regulations, medical and equipment requirements, cross
> country planning, etc.
>
> >Time is limited so obviously they cannot ask every thing. Is it possible
> >for a student to slip by on the
> > oral portion and just do well on practical and still pass?
>
> It's possible, but if you can't do well on the oral portion the practical
> might really kick your ass, particularly in the flight planning phase.

Hmm...that answers that question. We had some flight planning toward
end of class. That's when it really hit me that one actually has to
know what he's doing.

-Le Chaud Lapin-

[BDS[_2_]]

"Le Chaud Lapin" > wrote

> How difficult is the oral part?. Time is limited so obviously they
> cannot ask every thing. Is it possible for a student to slip by on the
> oral portion and just do well on practical and still pass?

Download and review the PTS - in general you can be asked about anything in
it. You can fail on the oral alone and never get to the flying portion of
the test. If you do that badly I suspect the examiner will be in touch with
the CFI who gave you the endorsement to take the practical.

Also note that the CFI who endorses you for the practical must also certify
that they have given you instruction in the areas you were found to be
deficient in when you took your knowledge test.

> Also, can FAA examiners act as instructors simultaneously or is there
> a rule forbidding it?

Depends on what you mean by instruction. If you fail to perform any
maneuver to the PTS standards you are probably not going to get instruction
on how to meet them and then also be rated as satisfactory. Same goes for
the oral.

CFIs who send too many poorly prepared students to examiners will probably
draw the attention of the local FSDO office at some point.

BDS

[CWatters[_2_]]

"mike regish" > wrote in message
. ..
> I think that the shape of the wing simply allows for a greater range of
> angles of attack. A sheet of plywood would provide lift, but only at a
very
> precise and small angle of attack.
>
> The airfoil shape allows the wing to
> provide lift through a much larger range of angles of attack.

Well sort of.

Thick wings do tend to operate over a wider range of angles than thin wings
but most subsonic wing sections will work from 0 to 10 degrees or more. It's
above 12 or 15 degrees that the section becomes more critical.

A conventional wing section with camber can produce +ve lift at zero degrees
AOA.

The zero lift angle (the angle at which no lift is produced) is actually
negative on many conventional sections.

Colin

> JMO.
>
> mike
> "Gatt" > wrote in message
> ...
> >
> > "Bertie the Bunyip" > wrote in message
> > ...
> >> Mxsmanic > wrote in
> >> :
> >>
> >>> Le Chaud Lapin writes:
> >>>
> >>>> Even though this (new) thread is not about what causes a wing to
lift,
> >>>> I just wanted to say for the record that I agree with this answer,
> >>>> that it is both AoA and curvature of the wing.
> >>>
> >>> It's just AOA.
> >>>
> >> Nope.
> >
> > There goes my Lapin = MX theory. Apologies to Chaud are probably in
> > order. (I probably apologize?)
> >
> > -c
> >
>
>

[Androcles]

"CWatters" > wrote in message
...
:
: "mike regish" > wrote in message
: . ..
: > I think that the shape of the wing simply allows for a greater range of
: > angles of attack. A sheet of plywood would provide lift, but only at a
: very
: > precise and small angle of attack.
: >
: > The airfoil shape allows the wing to
: > provide lift through a much larger range of angles of attack.
:
: Well sort of.
:
: Thick wings do tend to operate over a wider range of angles than thin
wings
: but most subsonic wing sections will work from 0 to 10 degrees or more.
It's
: above 12 or 15 degrees that the section becomes more critical.
:
: A conventional wing section with camber can produce +ve lift at zero
degrees
: AOA.
:
: The zero lift angle (the angle at which no lift is produced) is actually
: negative on many conventional sections.

Ever heard of Bernoulli?
Try this demonstration:
http://www.youtube.com/watch?v=KCcZyW-6-5o
A Tomahawk cruise missile uses its wings as a control surface more
than for lift. Straight and level is useful for the computer programmer.
He thinks that way.
http://www.youtube.com/watch?v=19XXTArAGaM

[Gatt]

"Le Chaud Lapin" > wrote in message
oups.com...
>
>> You ARE a student. You, IIRC, where discussing the logarithmic flaws of
>> the
>> "EB-6" if I remember correctly.
>
> Nope. I mentioned that I had followed the yellow and blue book page
> by page, and after that, I want to look at the EB-6 a little more,


I suggest you take a much closer look at your flight computer. I recommend
a Google Search of EB-6. Like I said, science is exact and requires
precision.


-c

[Jim Logajan]

"Gatt" > wrote:
> I recommend a Google Search of EB-6.

It's E-6B or just E6B. (I suppose E6-B is used also.)
But not EB-6.

I've been seeing the same typo repeated for quite a few postings on this
thread and until now had no reason to correct it.

[Le Chaud Lapin]

On Oct 11, 4:18 pm, "Gatt" > wrote:
> "Le Chaud Lapin" > wrote in ooglegroups.com...
>
>
>
> >> You ARE a student. You, IIRC, where discussing the logarithmic flaws of
> >> the
> >> "EB-6" if I remember correctly.
>
> > Nope. I mentioned that I had followed the yellow and blue book page
> > by page, and after that, I want to look at the EB-6 a little more,
>
> I suggest you take a much closer look at your flight computer. I recommend
> a Google Search of EB-6. Like I said, science is exact and requires
> precision.

????????

-Le Chaud Lapin-

[Marty Shapiro]

Jim Logajan > wrote in
:

> "Gatt" > wrote:
>> I recommend a Google Search of EB-6.
>
> It's E-6B or just E6B. (I suppose E6-B is used also.)
> But not EB-6.
>
> I've been seeing the same typo repeated for quite a few postings on this
> thread and until now had no reason to correct it.

Gee, Jim. the use of EB-6 was a dead give away that the sock puppet
didn't know **** from shinola.

--
Marty Shapiro
Silicon Rallye Inc.

(remove SPAMNOT to email me)

[Gatt]

"Jim Logajan" > wrote in message
.. .
> "Gatt" > wrote:
>> I recommend a Google Search of EB-6.
>
> It's E-6B or just E6B. (I suppose E6-B is used also.)
> But not EB-6.
>
> I've been seeing the same typo repeated for quite a few postings on this
> thread and until now had no reason to correct it.

Dang, I was trying to see how far it would go. I was being perfectly honest
when I said I never used an EB-6 for navigation.

-c

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
ups.com:

> On Oct 11, 12:38 pm, Mxsmanic > wrote:
>> Le Chaud Lapin writes:
>> > For example, remember 29.92 on barometer is good, but would
>> > be better if people had some idea of where 29.92 comes from. I asked
>> > around the room, and no one knew, not even the CFI.
>>
>> Seriously?
>
> Yes, seriously. The CFI was a very likeable person, a bit young,
> maybe mid 20's. I am sure he is competent as a pilot. I would not
> hesitate to fly with him. But personally, I have a real hard time
> being told to plug in numbers with no real understanding why. My
> ability to retain quickly drops to zero doing that.


Who, exaclty, besides yourself, of course, do you think you are kidding?

Bertie

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
oups.com:

> On Oct 11, 1:27 pm, "Gatt" > wrote:
>> "Le Chaud Lapin" > wrote in
>> glegroups.com...
>>
>> >> Why did you post "True Understanding Or Monkey Mode" about the
>> >> same thing in
>> >> rec.aviation.piloting. Are you accusing pilots of being monkeys?
>>
>> > No. If you read the posts, I was complaining about both the
>> > students and the pilots, mostly the students.
>>
>> You ARE a student. You, IIRC, where discussing the logarithmic flaws
>> of the "EB-6" if I remember correctly.
>
> Nope. I mentioned that I had followed the yellow and blue book page
> by page, and after that, I want to look at the EB-6 a little more, to
> try to understand if there were any relationships on the scales to
> help with memory. I asked if those relationships were linear, and one
> or two other people said that it was logarithm, and another person
> said that it is effectively a slide rule. I did not say whether it
> was linear or logarithmic, except for the temperature scale.
>
>> > As for the EB-6, no problem. I studied it in advance before the
>> > ground school class.
>>
>> I can tell. But, like I said in r.a.s, I made it clear through the
>> commercial license without ever once using an EB-6.
>
> So, my question might have been, which B A R R Y seems to have
> answered, is...
>
> "Given all the things in the Jeppesen $200 kit, are we expected to
> know those things or not?"
>
> I had been assuming that the FAA actually wants people to know. I had
> decided for myself not to take the KT yet even though I could probably
> pass (barely) right now.


No, I don't think they want you to know.



But i'll tell you ,

Send me $4,ooo and I'll tell all.


Bertie>
>
>

[Morgans[_2_]]

"Le Chaud Lapin" > wrote in message

> Hmm...I re-read my original 3 posts, two to rec.aviation.piloting, and
> I do not see much perversion in them. I have recopied the most
> controversial post for benefit of people in sci.physics.
idiot

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
oups.com:


>
> ????????
>


Hey, you could make this your sig, anthony..

Bertie
>

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
oups.com:

> On Oct 11, 1:31 pm, "Gatt" > wrote:
>> "Le Chaud Lapin" > wrote in
>> ooglegroups.com...
>>
>> > How difficult is the oral part?.
>>
>> It's easy if you know the material. It's going to be related to
>> practical things like airspace, regulations, medical and equipment
>> requirements, cross country planning, etc.
>>
>> >Time is limited so obviously they cannot ask every thing. Is it
>> >possible for a student to slip by on the
>> > oral portion and just do well on practical and still pass?
>>
>> It's possible, but if you can't do well on the oral portion the
>> practical might really kick your ass, particularly in the flight
>> planning phase.
>
> Hmm...that answers that question. We had some flight planning toward
> end of class. That's when it really hit me that one actually has to
> know what he's doing.


Ya think?

Bertie

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
oups.com:

> On Oct 11, 12:31 pm, "BDS" > wrote:
>> "Le Chaud Lapin" > wrote
>>
>> > As I mentioned, I was sitting in lobby of flight school one day,
>> > toward the end of ground school class, and there were 7-8 students
>> > cramming for their final and to take FAA KT. We were talking about
>> > what we think we should know, and one of the students hintet that
>> > understanding was not really important.
>>
>> Anyone who thinks that will be in for a surprise when they take the
>> oral portion of the practical test, if they get that far. Good
>> instructors will be checking their students' comprehension of the
>> required knowledge on a continuing basis as flight lessons progress.
>> I doubt that you would get a signoff for your practical from an
>> instructor who suspected that you were only at the rote learning
>> level.
>
> That brings me to next question:
>
> How difficult is the oral part?.


For you?Impossible,.

You have to listen to the question before you answer it, ya see.

Also, he will not come to your bedroom to give it.

the flight test is going to be even more difficult unless you've
installed dual controls on your computer.



Bertie

[mike regish]

The mad scientist! :-)

Excellent demonstrations. I liked when he held up the boomerang..."whatever
these do"

I used to make boomerangs out of 3/8" plywood. I made them by making each
wing an airfoil shape-the thick part of the airfoil on the outside on one
wing and on the inside of the other. Many commercial boomerangs have a sort
of aileron sanded into the bottom of one wing tip, but you don't need that.
As each wing starts moving forward in its rotation, that wing is moving
faster and provides more lift than the other, giving it an impulse to the
left. As the bottom wing comes around, it now provides more lift and gives
it another push-and so it goes. And the boomerang makes a curving flight
back to you.

mike

"Androcles"

> wrote in message
.uk...
>
> "CWatters" > wrote in message
> ...
> :
> : "mike regish" > wrote in message
> : . ..
> : > I think that the shape of the wing simply allows for a greater range
> of
> : > angles of attack. A sheet of plywood would provide lift, but only at a
> : very
> : > precise and small angle of attack.
> : >
> : > The airfoil shape allows the wing to
> : > provide lift through a much larger range of angles of attack.
> :
> : Well sort of.
> :
> : Thick wings do tend to operate over a wider range of angles than thin
> wings
> : but most subsonic wing sections will work from 0 to 10 degrees or more.
> It's
> : above 12 or 15 degrees that the section becomes more critical.
> :
> : A conventional wing section with camber can produce +ve lift at zero
> degrees
> : AOA.
> :
> : The zero lift angle (the angle at which no lift is produced) is actually
> : negative on many conventional sections.
>
> Ever heard of Bernoulli?
> Try this demonstration:
> http://www.youtube.com/watch?v=KCcZyW-6-5o
> A Tomahawk cruise missile uses its wings as a control surface more
> than for lift. Straight and level is useful for the computer programmer.
> He thinks that way.
> http://www.youtube.com/watch?v=19XXTArAGaM
>
>
>
>
>
>
>
>

[JGalban via AviationKB.com]

Le Chaud Lapin wrote:
>
>How difficult is the oral part?. Time is limited so obviously they
>cannot ask every thing.

I don't know where you got the idea that time for the oral is limited. A
good examiner will take as much time as he feels appropriate. I know a
recent applicant that had a 3 1/2 hr. oral.

John Galban=====>N4BQ (PA28-180)

--
Message posted via AviationKB.com
http://www.aviationkb.com/Uwe/Forums.aspx/aviation/200710/1

[Dudley Henriques[_2_]]

JGalban via AviationKB.com wrote:
> Le Chaud Lapin wrote:
>> How difficult is the oral part?. Time is limited so obviously they
>> cannot ask every thing.
>
> I don't know where you got the idea that time for the oral is limited. A
> good examiner will take as much time as he feels appropriate. I know a
> recent applicant that had a 3 1/2 hr. oral.
>
> John Galban=====>N4BQ (PA28-180)
>
...............and after this guy finishes impressing the examiner with
how much more he knows than the examiner knows, we might just be looking
at a new world record here :-))

--
Dudley Henriques

[Le Chaud Lapin]

On Oct 10, 11:43 am, JimboCat > wrote:
> On Oct 9, 4:08 pm, Le Chaud Lapin > wrote:
>
> > Comments from anyone who knows physics welcome.
>
> Hee, hee! You obviously don't know sci.physics!

You're right. :)

I've been watching sci.physics for the past few days for first time.

Certainly, while there are some really brilliant people here, not
everyone agrees on controversial topics, which is not a bad thing.

The difference I see between sci.physics and rec.aviation.piloting is
that, if someone attempts to re-examine long-standing accepted
theories, there is genuine debate, at least a lot more than ad hominem
attacks.

Perhaps I should have posed the question here first, then taken a
summary back to rec.aviation.piloting.

-Le Chaud Lapin-

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
oups.com:

> On Oct 10, 11:43 am, JimboCat > wrote:
>> On Oct 9, 4:08 pm, Le Chaud Lapin > wrote:
>>
>> > Comments from anyone who knows physics welcome.
>>
>> Hee, hee! You obviously don't know sci.physics!
>
> You're right. :)
>
> I've been watching sci.physics for the past few days for first time.
>
> Certainly, while there are some really brilliant people here, not
> everyone agrees on controversial topics, which is not a bad thing.
>
> The difference I see between sci.physics and rec.aviation.piloting is
> that, if someone attempts to re-examine long-standing accepted
> theories, there is genuine debate, at least a lot more than ad hominem
> attacks.
>

No, there is no debate. there is waht is, and then tere are k00ks.

I'll take a wild guess that you just might fall into the latter category.

Bertie

[george]

On Oct 12, 10:42 am, Jim Logajan > wrote:
> "Gatt" > wrote:
> > I recommend a Google Search of EB-6.
>
> It's E-6B or just E6B. (I suppose E6-B is used also.)
> But not EB-6.
>
> I've been seeing the same typo repeated for quite a few postings on this
> thread and until now had no reason to correct it.

I use the old term whizz wheel :-)
No batteries no comms requirements.
Just rotate the bezel and read the answer...

[Gatt]

"Le Chaud Lapin" > wrote in message
oups.com...

> The difference I see between sci.physics and rec.aviation.piloting is
> that, if someone attempts to re-examine long-standing accepted
> theories, there is genuine debate, at least a lot more than ad hominem
> attacks.

Guys like Kelly Johnson didn't design the P-38, U-2 and the SR-71 Blackbird
by not understanding aerospace physics. Basically, you came into r.a.p.
popping off like a sophomoric twit, and got called on it by everybody who
bothered to respond.

When I look out the window at 5,000 feet and see my wings continue to work
as described in the manual and the textbooks, just like they do in every
airplane I've flown, I'm dramatically more inclined to believe the physics
of the engineers who actually proved their worth by designed airplanes than
some usenet-know-it-all.

>Perhaps I should have posed the question here first, then taken a summary
>back to rec.aviation.piloting.

Perhaps before you come out here blathering about possible errors you see in
your flight computer, you should at least know what it's called. It's an
E6B, not an EB-6. (Been that way since before World War II.) Why invest
effort in a "genuine debate" with somebody who can't even correctly identify
his own tool? Even most student pilots learning in, as you called it,
"monkey mode", know that one.

"My question is: How many graduated students, in your opinion, have true
understanding of what is going on and how many have learned by
iliarity?" -you

-c
r.a.p.

[Le Chaud Lapin]

On Oct 15, 5:32 pm, "Gatt" > wrote:
> "Le Chaud Lapin" > wrote in
> Guys like Kelly Johnson didn't design the P-38, U-2 and the SR-71 Blackbird
> by not understanding aerospace physics. Basically, you came into r.a.p.
> popping off like a sophomoric twit, and got called on it by everybody who
> bothered to respond.

The fact remains that there is still considerable dispute about the
fundamentals of the dynamics of airfoils from multipile prominent
organizations involved in the theory of flight.

In the 2-3 weeks that I have been searching, I have found, with help
of others, countless examples of the fundamentals being disputed by
people who write textbooks, scientific papers, etc. There is also the
link at NASA that claims that many of the textbooks are wrong. I read
last night in another piloting book, again, that the common belief
about the dynamics of airfoils is wrong, but the explanation of what
was right contrasted with the other textbook's explanation.

> When I look out the window at 5,000 feet and see my wings continue to work
> as described in the manual and the textbooks, just like they do in every
> airplane I've flown, I'm dramatically more inclined to believe the physics
> of the engineers who actually proved their worth by designed airplanes than
> some usenet-know-it-all.

Who said your textbooks are right? How do you determine that your
textbook is right and the others are wrong? It is not necessary for
you to have (true) understanding of airfoil dynamics to be able to fly
an aircraft. Many pilots might not understand the physics of
electrogmagnetic propagation, but they still use the radio.

My question was a statement of my opinion, something that I, like all
USENET posters, are entitled to. If you disagree with my opinion, it
is your right to not participate in the conversation.

The insults are really unnecessary. I read my original posts, and
there were little in them to warrant personal attacks other than that
I was broaching a subject that you and others felt should not be
discussed, at least by someone like me.

> Perhaps before you come out here blathering about possible errors you see in
> your flight computer, you should at least know what it's called. It's an
> E6B, not an EB-6. (Been that way since before World War II.) Why invest
> effort in a "genuine debate" with somebody who can't even correctly identify
> his own tool? Even most student pilots learning in, as you called it,
> "monkey mode", know that one.

E6B, EB-6...this has little to do with my original question. And what
it is called has no bearing on how it functions. And the topic I
introduced had nothing to do with an E6B, nor did I ever dispute teh
operation of it.

-Le Chaud Lapin-

[Gatt]

"Le Chaud Lapin" > wrote in message
ups.com...

> I read last night in another piloting book, again, that the common belief
> about the dynamics of airfoils is wrong,

Yeah? Which one?

>> I'm dramatically more inclined to believe the physics
>> of the engineers who actually proved their worth by designed airplanes
>> than
>> some usenet-know-it-all.
>
> Who said your textbooks are right?

No kidding. I mean, HOW DO I KNOW THE AIRPLANE I'M FLYING ACTUALLY FLIES?!


>How do you determine that your textbook is right and the others are wrong?

Why do you repeatedly snip the bits about Kelly Johnson, the SR-71, etc?

> E6B, EB-6...this has little to do with my original question.

It shows your lack of understanding of the subject matter and your lack of
attention to detail. As I told you before, physics is an exact science.
If you're unable to properly name the hammer, you're not going to convince
anybody you're a useful carpenter.

-c

[Androcles]

"Le Chaud Lapin" > wrote in message
oups.com...
: On Oct 15, 6:42 pm, "Gatt" > wrote:
: > "Le Chaud Lapin" > wrote in
oglegroups.com...
: >
: > > I read last night in another piloting book, again, that the common
belief
: > > about the dynamics of airfoils is wrong,
: >
: > Yeah? Which one?
:
: I'd have to go back to bookstore to find the name.

AHAHAHAHAHAHA!
Or back to sleep to dream again...

[Mxsmanic]

Gatt writes:

> Guys like Kelly Johnson didn't design the P-38, U-2 and the SR-71 Blackbird
> by not understanding aerospace physics.

Actually there was a lot of trial and error involved. They experimented and
found what worked.

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
oups.com:

> On Oct 15, 6:42 pm, "Gatt" > wrote:
>> "Le Chaud Lapin" > wrote in
>> oglegroups.com...
>>
>> > I read last night in another piloting book, again, that the common
>> > belief about the dynamics of airfoils is wrong,
>>
>> Yeah? Which one?
>
> I'd have to go back to bookstore to find the name.
>
>> >> I'm dramatically more inclined to believe the physics
>> >> of the engineers who actually proved their worth by designed
>> >> airplanes than
>> >> some usenet-know-it-all.
>>
>> > Who said your textbooks are right?
>>
>> No kidding. I mean, HOW DO I KNOW THE AIRPLANE I'M FLYING ACTUALLY
>> FLIES?!
>
> Seeing is believing.
>
>> >How do you determine that your textbook is right and the others are
>> >wrong?
>>
>> Why do you repeatedly snip the bits about Kelly Johnson, the SR-71,
>> etc?
>
> The snipping was not intended. In any case, are you sayin that Kelly
> Johnson is the final authority on the dynamics of flight? Are you
> saying that the design of the SR-71 would not have been possible if
> the dynamics of flight were not resolved? If there is resolution, why
> so much disagreement among experts?

No there isn't

At the very least, the textbooks
> are wrong.
>


No they aren;t

You gotta go deeper than the "little golden book of airplanes" to get a
grip on aeodynamics, fjukwit.





Bertie
>> > E6B, EB-6...this has little to do with my original question.
>>
>> It shows your lack of understanding of the subject matter and your
>> lack of attention to detail. As I told you before, physics is an
>> exact science. If you're unable to properly name the hammer, you're
>> not going to convince anybody you're a useful carpenter.
>
> So basically you are saying that people who make typographical errors
> demonstrate their lack of understanding.
>
> What is it that you do not understand by writing "iliarity" in the
> post you wrote today?
>
> -Le Chaud Lapin-
>
>

[Bertie the Bunyip[_19_]]

Mxsmanic > wrote in
:

> Gatt writes:
>
>> Guys like Kelly Johnson didn't design the P-38, U-2 and the SR-71
>> Blackbird by not understanding aerospace physics.
>
> Actually there was a lot of trial and error involved. They
> experimented and found what worked.
>


Like you'd know, fjukkwit.

Bertie

[Le Chaud Lapin]

On Oct 15, 7:54 pm, "Androcles" > wrote:
> "Le Chaud Lapin" > wrote in ooglegroups.com...
> : On Oct 15, 6:42 pm, "Gatt" > wrote:
> : > "Le Chaud Lapin" > wrote in
> oglegroups.com...
> : >
> : > > I read last night in another piloting book, again, that the common
> belief
> : > > about the dynamics of airfoils is wrong,
> : >
> : > Yeah? Which one?
> :
> : I'd have to go back to bookstore to find the name.
>
> AHAHAHAHAHAHA!
> Or back to sleep to dream again...

Barry Schiff, in "The Proficient Pilot", "An AOPA Book", writes on
page 2:

"There is, for example, this amusing fable: "Air flowing above the
wing has a greater distance to travel (because of camber) than air
flowing beneath the wing. Therefore, air above the wing must travel
faster so as to arrive at the wing's trailing edge at the same time as
air flowing underneath. This is pure nonsense."

He goes on to write:

"Pilot's are generally curious, intelligent breaed who desire to learn
as much as possible about the science of flight. This seprates them
from most automobile drivers who don't konw and couldn't care less
about the different between a distributor and a differential."

This last paragraph sounds reasonable, except for the fact that all
but 3 or 4 of the pilots that I "met" in rec.piloting.aviation did not
seem to fit this characterization. Even though there is undeniable
evidence both in print and on the WWW that there is not conscensus
about the dynamics of lift, there is been vehement rejection by almost
all (except the 3-4 mentioned) to broach the topic.

He then writes:

"Pilots use lift; their lives depend on it. They read and talk about
it, are quizzed about it, and even try explaining this miracle of
flight to their lay friends. The problem is that most pilots really
don't know how lift is created; they only think they do."

Hmmm...

Before I started reading his book, I had the idea (don't ask me what
possessed me to make such an assumption) that most pilots understood
the dynamics of flight. I did have personal experiences before taking
ground school that made me almost sure that the pilots that I had
spoken with personally did not understand the physics (not really),
but I thought this was due to my own bad luck. Then after ground
school and reading the Jeppesen description of lift, the NASA site,
the sites at some aero/astro departments in the USA, books at the
bookstore, and especially after my brief visit to
rec.aviation.piloting, I am inclined to believe what Barry Schiff
wrote above.

Also, if the pilots in rec.aviation.piloting really understood the
dynamics of lift, they might not have responded so vitriollically to
my original post. At the very least, there would have been open
discussion without personal attacks.

Furthermore, I have visited 4 or 5 other sites tonight about the
theory of lift, and each of them said the same thing: "the other
writers think they know, but they don't." In fact, while writing this
very post, I noticed a Google ad in the right column entitled "A
Physical Description of Lift" Here is what is written in the first
paragraph:

"Almost everyone today has flown in an airplane. Many ask the simple
question "what makes an airplane fly?" The answer one frequently gets
is misleading and often just plain wrong."
(http://groups.google.com/group/sci.physics/browse_frm/thread/
f0ee729cabbcb903/#)

I cannot see how much clearer it could be. More than 90% of every
description of lift I have seen in print and on the WWW have all said
basically the same thing: "other people got it wrong."

Not everyone can be right when each of them are saying that some of
the others are wrong.

Therefore, one could conclude that the vitriolic attacks against me
personally for broaching the subject might be a sign of something
deeper, perhaps the attackers' distaste for having the topic openly
discussed.

And yet still, after my 1st post, after more than 600 replies
cummulative, not one pilot has dared answered the question why the
bottom paper rises.

Perhaps I will re-post the experiment in sci.physics to see what the
physicists think.

-Le Chaud Lapin-

[Androcles]

"Le Chaud Lapin" > wrote in message
ps.com...
: On Oct 15, 7:54 pm, "Androcles" > wrote:
: > "Le Chaud Lapin" > wrote in
ooglegroups.com...
: > : On Oct 15, 6:42 pm, "Gatt" > wrote:
: > : > "Le Chaud Lapin" > wrote in
: > oglegroups.com...
: > : >
: > : > > I read last night in another piloting book, again, that the common
: > belief
: > : > > about the dynamics of airfoils is wrong,
: > : >
: > : > Yeah? Which one?
: > :
: > : I'd have to go back to bookstore to find the name.
: >
: > AHAHAHAHAHAHA!
: > Or back to sleep to dream again...
:
: Barry Schiff, in "The Proficient Pilot", "An AOPA Book", writes on
: page 2:
:
: "There is, for example, this amusing fable: "Air flowing above the
: wing has a greater distance to travel (because of camber) than air
: flowing beneath the wing. Therefore, air above the wing must travel
: faster so as to arrive at the wing's trailing edge at the same time as
: air flowing underneath. This is pure nonsense."

Since it is true Schiff must be a raving lunatic. Maybe you don't
understand that travelling the greater path in the same time involves
a greater speed.

[BDS]

"Le Chaud Lapin" > wrote>

> Therefore, one could conclude that the vitriolic attacks against me
> personally for broaching the subject might be a sign of something
> deeper, perhaps the attackers' distaste for having the topic openly
> discussed.
>
> And yet still, after my 1st post, after more than 600 replies
> cummulative, not one pilot has dared answered the question why the
> bottom paper rises.

[Yawn] Perhaps no one here is interested in discussing this with you and
going out of their way to help you to learn because of your abrasive and
insulting approach. I think you will find that pilots with a considerable
amount of experience no longer feel like they have anything to prove, so the
"insulting challenge" approach does not work with them. IOW, they are not
interested in trying to impress you.

> Perhaps I will re-post the experiment in sci.physics to see what the
> physicists think.

Please do. Might I suggest you try a different approach when you ask
someone for help?

BDS

[Thomas]

On 9 Oct, 21:08, Le Chaud Lapin > wrote:
> Hi All,
>
> There is a long discussion ongoing in rec.aviation.piloting about what
> causes lift on a plane. You can read from the link below. Please
> note that about 80% of the post are mostly ad hominem attacks and
> should be ignored. There are some small bits of real discussion.
>
> http://groups.google.com/group/rec.aviation.piloting/browse_frm/threa...
>
> I am an electrical engineer with experience in analag design and
> software, with math and physics background that you would expect of an
> electrical engineer.
>
> There are many points made in the discussion, but I would like to
> focus on one in particular for the sake of progress.
>
> There are people in the pilot's group, who think that lift on a wing
> is analyzed as such:
>
> 1. There is air on outside of top of wing that is pushing down, but
> reduced because of aerodynamics.
> 2. The *inside* of the wing contains air pushing up against the
> underside of top of wing .
> 3. Let us ignore that the same air inside the wing pushes down on the
> overside of bottom part of wing.
> 3. The difference in pressure against the underside of the top wing on
> the inside of wing and top of wing on outside, is what gives plane
> lift.
>
> Note that they ignore the pressure inside the wing that pushes
> downward on the wing.
>
> I am trying to convince them that, if there is air on the inside of
> the wing, it pushes against all sides of the inside of the wing,
> including both top underside and bottom overside, and thereby
> nullifying any effect it would have on the wing. Lift is caused by a
> difference in pressure between the underside of the bottom of the
> wing, and the overside of the top of the wing.
>
> I count 8-9 people in the group who are utterly convinced that I am
> inept at physics, mathematics, etc.
>
> Note that some of these people have been flying aircraft for years,
> even decades, while I am still a student pilot.
>
> Comments from anyone who knows physics welcome.
>
> -Le Chaud Lapin-


You may want to check out my web pages http://www.physicsmyths.org.uk/bernoulli.htm
and http://www.physicsmyths.org.uk/drag.htm for a closer examination
of the physics behind the aerodynamic lift and drag.

The main point I am making there is that it is physically nonsense to
claim that changing merely the tangential velocity of the air stream
relative to the surface would in any way produce a resultant force (at
least for a non-viscous gas). What one needs for a pressure change
(and thus a force) on the surface is a change in the numbers and/or
the velocity of the molecules hitting it, i.e. it is only the vertical
component of the velocity that is relevant here. Only this can produce
the lift for an airfoil, either because of the increased number of
collisions on the lower side or the decreased number of collisions on
the upper side (both situations lead to a lift). And it should be
obvious that for this to be the case, one must either have the lower
side of the wing facing to a certain degree into the airstream, and/or
the upper side facing to a certain degree opposite to the airstream.
This is why one either needs a certain 'angle of attack' or a
correspondingly shaped airfoil. And it should be obvious that in order
to have an asymmetric force (i.e. a higher upward than downward force)
one needs the surfaces of the airfoil to be orientated in some way
asymmetrical relatively to the airstream. So a perfectly symmetrical
airfoil (front to back) at a zero angle of attack (like I indicated in
Fig.1 on my page http://www.physicsmyths.org.uk/bernoulli.htm ) should
not produce any lift as the upward force (from the rear part) is
exactly equal to the downward force (from the front part). All that
would happen is that the wing experiences an anti-clockwise torque.
This is the reason why the rear part of the wing (behind the apex)
must always have a larger surface than the front part. At least I have
yet to see an airfoil where this is not the case and where it can be
used at a zero angle of attack.
(the Bernoulli principle is in direct contradiction to this as it
would also predict a lift for a perfectly symmetric airfoil in this
sense).

Thomas

[Le Chaud Lapin]

On Oct 16, 5:01 am, "BDS" > wrote:
> "Le Chaud Lapin" > wrote>
>
> > Therefore, one could conclude that the vitriolic attacks against me
> > personally for broaching the subject might be a sign of something
> > deeper, perhaps the attackers' distaste for having the topic openly
> > discussed.
>
> > And yet still, after my 1st post, after more than 600 replies
> > cummulative, not one pilot has dared answered the question why the
> > bottom paper rises.
>
> [Yawn] Perhaps no one here is interested in discussing this with you and
> going out of their way to help you to learn because of your abrasive and
> insulting approach. I think you will find that pilots with a considerable
> amount of experience no longer feel like they have anything to prove, so the
> "insulting challenge" approach does not work with them. IOW, they are not
> interested in trying to impress you.

What about my orignial post is abrasive and insulting?

> > Perhaps I will re-post the experiment in sci.physics to see what the
> > physicists think.
>
> Please do. Might I suggest you try a different approach when you ask
> someone for help?

-Le Chaud Lapin-

[Le Chaud Lapin]

On Oct 16, 3:47 am, "Androcles" > wrote:
> "Le Chaud Lapin" > wrote in glegroups.com...
> : On Oct 15, 7:54 pm, "Androcles" > wrote:
> : > "Le Chaud Lapin" > wrote in
> ooglegroups.com...
> : > : On Oct 15, 6:42 pm, "Gatt" > wrote:
> : > : > "Le Chaud Lapin" > wrote in
> : > oglegroups.com...
> : > : >
> : > : > > I read last night in another piloting book, again, that the common
> : > belief
> : > : > > about the dynamics of airfoils is wrong,
> : > : >
> : > : > Yeah? Which one?
> : > :
> : > : I'd have to go back to bookstore to find the name.
> : >
> : > AHAHAHAHAHAHA!
> : > Or back to sleep to dream again...
> :
> : Barry Schiff, in "The Proficient Pilot", "An AOPA Book", writes on
> : page 2:
> :
> : "There is, for example, this amusing fable: "Air flowing above the
> : wing has a greater distance to travel (because of camber) than air
> : flowing beneath the wing. Therefore, air above the wing must travel
> : faster so as to arrive at the wing's trailing edge at the same time as
> : air flowing underneath. This is pure nonsense."
>
> Since it is true Schiff must be a raving lunatic. Maybe you don't
> understand that travelling the greater path in the same time involves
> a greater speed.

Perhaps you could explain in detail what you mean by this last
statement. I am sure that there are plenty of people here would would
like, for once, that a pilot explains what s/he means by this.

-Le Chaud Lapin-

[Gatt]

"Le Chaud Lapin" > wrote in message
oups.com...

> Are you saying that the design of the SR-71 would not have been possible
> if
> the dynamics of flight were not resolved?

LMAO! Read what you just wrote. Gee, the SR-71 would have been TOTALLY
possible if the designer didn't know what he was doing. I guess he just got
lucky. What your airplane design look like?


>> > E6B, EB-6...this has little to do with my original question.

> So basically you are saying that people who make typographical errors
> demonstrate their lack of understanding.

It wasn't a typo. You said it repeatedly in multiple newsgroups.

Sorry. Your entertainment value has pretty much expired. Good luck in the
future.

-c

[Gatt]

> Barry Schiff, in "The Proficient Pilot", "An AOPA Book", writes on
> page 2:
>
> "There is, for example, this amusing fable: "Air flowing above the
> wing has a greater distance to travel (because of camber) than air
> flowing beneath the wing. Therefore, air above the wing must travel
> faster so as to arrive at the wing's trailing edge at the same time as
> air flowing underneath. This is pure nonsense."

Like I said. Upper camber is a conspiracy by the aluminum manufacturers to
sell more metal... Bournoulli was a shill.


-c

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
ps.com:


>
> Perhaps I will re-post the experiment in sci.physics to see what the
> physicists think.
>

I await the outcome of that with a giant yawn.


Bertie

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
ups.com:

> On Oct 16, 3:47 am, "Androcles" > wrote:
>> "Le Chaud Lapin" > wrote in
>> glegroups.com...
>> : On Oct 15, 7:54 pm, "Androcles" > wrote:
>> : > "Le Chaud Lapin" > wrote in
>> ooglegroups.com...
>> : > : On Oct 15, 6:42 pm, "Gatt" > wrote:
>> : > : > "Le Chaud Lapin" > wrote in
>> : > messagenews:1192488325.423647.30120
@i38g2000prf.googlegroups.com..
>> : > .
>> : > : >
>> : > : > > I read last night in another piloting book, again, that the
>> : > : > > common
>> : > belief
>> : > : > > about the dynamics of airfoils is wrong,
>> : > : >
>> : > : > Yeah? Which one?
>> : > :
>> : > : I'd have to go back to bookstore to find the name.
>> : >
>> : > AHAHAHAHAHAHA!
>> : > Or back to sleep to dream again...
>> :
>> : Barry Schiff, in "The Proficient Pilot", "An AOPA Book", writes on
>> : page 2:
>> :
>> : "There is, for example, this amusing fable: "Air flowing above the
>> : wing has a greater distance to travel (because of camber) than air
>> : flowing beneath the wing. Therefore, air above the wing must travel
>> : faster so as to arrive at the wing's trailing edge at the same time
>> : as air flowing underneath. This is pure nonsense."
>>
>> Since it is true Schiff must be a raving lunatic. Maybe you don't
>> understand that travelling the greater path in the same time involves
>> a greater speed.
>
> Perhaps you could explain in detail what you mean by this last
> statement. I am sure that there are plenty of people here would would
> like, for once, that a pilot explains what s/he means by this.
>


What's it matter? Yo'll never be a pilot. Any math that wil enable you
to dial up for home delivered pizza and escargot should suffice. #



Bertie
>
>

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
oups.com:

> On Oct 16, 5:01 am, "BDS" > wrote:
>> "Le Chaud Lapin" > wrote>
>>
>> > Therefore, one could conclude that the vitriolic attacks against me
>> > personally for broaching the subject might be a sign of something
>> > deeper, perhaps the attackers' distaste for having the topic openly
>> > discussed.
>>
>> > And yet still, after my 1st post, after more than 600 replies
>> > cummulative, not one pilot has dared answered the question why the
>> > bottom paper rises.
>>
>> [Yawn] Perhaps no one here is interested in discussing this with you
>> and going out of their way to help you to learn because of your
>> abrasive and insulting approach. I think you will find that pilots
>> with a considerable amount of experience no longer feel like they
>> have anything to prove, so the "insulting challenge" approach does
>> not work with them. IOW, they are not interested in trying to
>> impress you.
>
> What about my orignial post is abrasive and insulting?
>


Bwawahwhahwhahwhahwhahhwhahwhahwwhahwhahwhahhwhahw hahwwhahwhahwhahhwhahw
hahwwhahwhahwhahhwhahwhahwwhahwhahwhahhwhahwhahwwh ahwhahwhahhwhahwhahwwh
ahwhahwhahhwhahwhahwwhahwhahwhahhwhahwhahwwhahwhah whahhwhah



Bertie
>
>
>

[Le Chaud Lapin]

On Oct 16, 6:31 am, Thomas > wrote:
> On 9 Oct, 21:08, Le Chaud Lapin > wrote:
> You may want to check out my web pageshttp://www.physicsmyths.org.uk/bernoulli.htm
> andhttp://www.physicsmyths.org.uk/drag.htm for a closer examination
> of the physics behind the aerodynamic lift and drag.
>
> The main point I am making there is that it is physically nonsense to
> claim that changing merely the tangential velocity of the air stream
> relative to the surface would in any way produce a resultant force (at
> least for a non-viscous gas).

> What one needs for a pressure change
> (and thus a force) on the surface is a change in the numbers and/or
> the velocity of the molecules hitting it, i.e. it is only the vertical
> component of the velocity that is relevant here. Only this can produce
> the lift for an airfoil, either because of the increased number of
> collisions on the lower side or the decreased number of collisions on
> the upper side (both situations lead to a lift).

I agree, but there are some that seem to think the contrary, as you
know, with the Coanda effect.
http://en.wikipedia.org/wiki/Coand%C4%83_effect

What is troubling about many of these theories is that, at the precise
moment where the reader is most alert in anticipation of the meat of
the explanation, the hand-waving begins. In the link above, the clause
entitled Causes, it is written:

"The effect of a spoon apparently attracting a flow of water is caused
by this effect as well, since the flow of water entrains gases to flow
down along the stream, and these gases are then pulled, along with the
flow of water, in towards the spoon, as a result of the pressure
differential. "

Hmmm...."and these gases are then pulled"...

pulled? By what?

> And it should be
> obvious that for this to be the case, one must either have the lower
> side of the wing facing to a certain degree into the airstream, and/or
> the upper side facing to a certain degree opposite to the airstream.
> This is why one either needs a certain 'angle of attack' or a
> correspondingly shaped airfoil. And it should be obvious that in order
> to have an asymmetric force (i.e. a higher upward than downward force)
> one needs the surfaces of the airfoil to be orientated in some way
> asymmetrical relatively to the airstream. So a perfectly symmetrical
> airfoil (front to back) at a zero angle of attack (like I indicated in
> Fig.1 on my pagehttp://www.physicsmyths.org.uk/bernoulli.htm) should
> not produce any lift as the upward force (from the rear part) is
> exactly equal to the downward force (from the front part). All that
> would happen is that the wing experiences an anti-clockwise torque.
> This is the reason why the rear part of the wing (behind the apex)
> must always have a larger surface than the front part. At least I have
> yet to see an airfoil where this is not the case and where it can be
> used at a zero angle of attack.
> (the Bernoulli principle is in direct contradiction to this as it
> would also predict a lift for a perfectly symmetric airfoil in this
> sense).

I just read both your web pages.

BTW, your explanation of d'Alembert's Paradox and the blow-over-paper-
attached-to-table experiment could both use diagrams. I am trying the
blow over the paper experiment now and I am not sure if I am doing it
as you described. Could you provide a more vivid description so I can
make sure?

-Le Chaud Lapin-

[Androcles]

"Le Chaud Lapin" > wrote in message
ups.com...
: On Oct 16, 3:47 am, "Androcles" > wrote:
: > "Le Chaud Lapin" > wrote in
glegroups.com...
: > : On Oct 15, 7:54 pm, "Androcles" > wrote:
: > : > "Le Chaud Lapin" > wrote in
: > ooglegroups.com...
: > : > : On Oct 15, 6:42 pm, "Gatt" > wrote:
: > : > : > "Le Chaud Lapin" > wrote in
: > : > oglegroups.com...
: > : > : >
: > : > : > > I read last night in another piloting book, again, that the
common
: > : > belief
: > : > : > > about the dynamics of airfoils is wrong,
: > : > : >
: > : > : > Yeah? Which one?
: > : > :
: > : > : I'd have to go back to bookstore to find the name.
: > : >
: > : > AHAHAHAHAHAHA!
: > : > Or back to sleep to dream again...
: > :
: > : Barry Schiff, in "The Proficient Pilot", "An AOPA Book", writes on
: > : page 2:
: > :
: > : "There is, for example, this amusing fable: "Air flowing above the
: > : wing has a greater distance to travel (because of camber) than air
: > : flowing beneath the wing. Therefore, air above the wing must travel
: > : faster so as to arrive at the wing's trailing edge at the same time as
: > : air flowing underneath. This is pure nonsense."
: >
: > Since it is true Schiff must be a raving lunatic. Maybe you don't
: > understand that travelling the greater path in the same time involves
: > a greater speed.
:
: Perhaps you could explain in detail what you mean by this last
: statement. I am sure that there are plenty of people here would would
: like, for once, that a pilot explains what s/he means by this.

Really?
Ok, for plenty of cretins such as yourself...

Travelling 70 miles (distance) in one hour (duration of time)
is a speed of 70 mph by definition.
100 miles (the greater distance) in the same time (1 hour)
is 100 mph.
100 mph is faster than 70 mph.
People unaware of this simple fact are prone to getting
speeding tickets and losing their license.
Aircraft pilots are even more aware of it than motorists,
using their stop watches to compute distance.

In this video the air moves MUCH faster over the top of the wing
than it does over the bottom:
http://www.youtube.com/watch?v=KCcZyW-6-5o

Now you can go back to sleep and dream of Barry Schiff and
his "nonsense".

[Le Chaud Lapin]

On Oct 16, 9:53 am, "Gatt" > wrote:
> > Barry Schiff, in "The Proficient Pilot", "An AOPA Book", writes on
> > page 2:
>
> > "There is, for example, this amusing fable: "Air flowing above the
> > wing has a greater distance to travel (because of camber) than air
> > flowing beneath the wing. Therefore, air above the wing must travel
> > faster so as to arrive at the wing's trailing edge at the same time as
> > air flowing underneath. This is pure nonsense."
>
> Like I said. Upper camber is a conspiracy by the aluminum manufacturers to
> sell more metal... Bournoulli was a shill.

You wrote repeatedly that lack of attention to detail (mostly due to
my spelling errors) indicated lack of understangind, was not becoming
of a critical thinker, etc...yet you keep making spelling errors
youself. :)

I never disputed Bernoulli's Principle, not once. I said that there
was a lot of hand-waving going on when pilots uttered greater/lesser/
camber/Bernoulli in the same sentence.

Bernoulli's principle is correct.

That the camber influences lift is correct.

But how the camber influences lift has nothing to do with greater
distances traveled, IMO.

-Le Chaud Lapin-

[Le Chaud Lapin]

On Oct 16, 10:20 am, "Androcles" > wrote:
> "Le Chaud Lapin" > wrote in oglegroups.com...
> : On Oct 16, 3:47 am, "Androcles" > wrote:
> : > "Le Chaud Lapin" > wrote in
> glegroups.com...
> : > : On Oct 15, 7:54 pm, "Androcles" > wrote:
> : > : > "Le Chaud Lapin" > wrote in
> : > ooglegroups.com...
> : > : > : On Oct 15, 6:42 pm, "Gatt" > wrote:
> : > : > : > "Le Chaud Lapin" > wrote in
> : > : > oglegroups.com...
> : > : > : >
> : > : > : > > I read last night in another piloting book, again, that the
> common
> : > : > belief
> : > : > : > > about the dynamics of airfoils is wrong,
> : > : > : >
> : > : > : > Yeah? Which one?
> : > : > :
> : > : > : I'd have to go back to bookstore to find the name.
> : > : >
> : > : > AHAHAHAHAHAHA!
> : > : > Or back to sleep to dream again...
> : > :
> : > : Barry Schiff, in "The Proficient Pilot", "An AOPA Book", writes on
> : > : page 2:
> : > :
> : > : "There is, for example, this amusing fable: "Air flowing above the
> : > : wing has a greater distance to travel (because of camber) than air
> : > : flowing beneath the wing. Therefore, air above the wing must travel
> : > : faster so as to arrive at the wing's trailing edge at the same time as
> : > : air flowing underneath. This is pure nonsense."
> : >
> : > Since it is true Schiff must be a raving lunatic. Maybe you don't
> : > understand that travelling the greater path in the same time involves
> : > a greater speed.
> :
> : Perhaps you could explain in detail what you mean by this last
> : statement. I am sure that there are plenty of people here would would
> : like, for once, that a pilot explains what s/he means by this.
>
> Really?
> Ok, for plenty of cretins such as yourself...
>
> Travelling 70 miles (distance) in one hour (duration of time)
> is a speed of 70 mph by definition.
> 100 miles (the greater distance) in the same time (1 hour)
> is 100 mph.
> 100 mph is faster than 70 mph.
> People unaware of this simple fact are prone to getting
> speeding tickets and losing their license.
> Aircraft pilots are even more aware of it than motorists,
> using their stop watches to compute distance.

> In this video the air moves MUCH faster over the top of the wing
> than it does over the bottom:
> http://www.youtube.com/watch?v=KCcZyW-6-5o

I just looked at this video.

What you wrote and what this video demonstrates are two entirely
different things. There is no reason to say that the air moving above
the wing must meet beneath the wing.

I keep hearing people say,

"The air moves faster, therefore Bernoulli's Principle must be
invoked."

The thesis of what I have been saying all along can be seeing in an
inversion of this sentence.

"It is Bernoulli's principle that causes the air to flow faster."

In particular, it is the pressure gradient that causes the air in the
contstriction to flow faster. This same pressure gradient exists
above a wing in an air craft, and it has nothing to do with the
distance traveled. The camber of the wing is carefully designed my
airfcraft manufacturers to incudes, as much as possible, this pressure
gradient, at a particular speed, but *with* the conflicting
requirement that resulting drag must be reduced. This is why I said
earlier that pressure at the front of the wing is not necessarily bad.
It is desirable, but it also causes some laminar drag. Intuitively,
one can see what the edge must not be made sharp - doing that would
elimate the very pressure that is need to bring about the pressure
gradient.

> Now you can go back to sleep and dream of Barry Schiff and
> his "nonsense".

-Le Chaud Lapin-

[Morgans[_2_]]

"Bertie the Bunyip" > wrote

>
> What's it matter? Yo'll never be a pilot. Any math that wil enable you
> to dial up for home delivered pizza and escargot should suffice. #

Are you kidding? He doesn't have a job to provide enough money for
escargot.

The only escargot he is going to see is from the snails he plucks out of the
river!

Mmmmmm!
--
Jim in NC

[Androcles]

"Le Chaud Lapin" > wrote in message
ups.com...
: On Oct 16, 10:20 am, "Androcles" > wrote:
: > "Le Chaud Lapin" > wrote in
oglegroups.com...
: > : On Oct 16, 3:47 am, "Androcles" > wrote:
: > : > "Le Chaud Lapin" > wrote in
: > glegroups.com...
: > : > : On Oct 15, 7:54 pm, "Androcles" > wrote:
: > : > : > "Le Chaud Lapin" > wrote in
: > : > ooglegroups.com...
: > : > : > : On Oct 15, 6:42 pm, "Gatt" > wrote:
: > : > : > : > "Le Chaud Lapin" > wrote in
: > : > : >
oglegroups.com...
: > : > : > : >
: > : > : > : > > I read last night in another piloting book, again, that
the
: > common
: > : > : > belief
: > : > : > : > > about the dynamics of airfoils is wrong,
: > : > : > : >
: > : > : > : > Yeah? Which one?
: > : > : > :
: > : > : > : I'd have to go back to bookstore to find the name.
: > : > : >
: > : > : > AHAHAHAHAHAHA!
: > : > : > Or back to sleep to dream again...
: > : > :
: > : > : Barry Schiff, in "The Proficient Pilot", "An AOPA Book", writes on
: > : > : page 2:
: > : > :
: > : > : "There is, for example, this amusing fable: "Air flowing above the
: > : > : wing has a greater distance to travel (because of camber) than air
: > : > : flowing beneath the wing. Therefore, air above the wing must
travel
: > : > : faster so as to arrive at the wing's trailing edge at the same
time as
: > : > : air flowing underneath. This is pure nonsense."
: > : >
: > : > Since it is true Schiff must be a raving lunatic. Maybe you don't
: > : > understand that travelling the greater path in the same time
involves
: > : > a greater speed.
: > :
: > : Perhaps you could explain in detail what you mean by this last
: > : statement. I am sure that there are plenty of people here would would
: > : like, for once, that a pilot explains what s/he means by this.
: >
: > Really?
: > Ok, for plenty of cretins such as yourself...
: >
: > Travelling 70 miles (distance) in one hour (duration of time)
: > is a speed of 70 mph by definition.
: > 100 miles (the greater distance) in the same time (1 hour)
: > is 100 mph.
: > 100 mph is faster than 70 mph.
: > People unaware of this simple fact are prone to getting
: > speeding tickets and losing their license.
: > Aircraft pilots are even more aware of it than motorists,
: > using their stop watches to compute distance.
:
: > In this video the air moves MUCH faster over the top of the wing
: > than it does over the bottom:
: > http://www.youtube.com/watch?v=KCcZyW-6-5o
:
: I just looked at this video.
:
: What you wrote and what this video demonstrates are two entirely
: different things. There is no reason to say that the air moving above
: the wing must meet beneath the wing.

What do you think it meets, water?



:
: I keep hearing people say,
:
: "The air moves faster, therefore Bernoulli's Principle must be
: invoked."

That's right.

:
: The thesis of what I have been saying all along can be seeing in an
: inversion of this sentence.
:
: "It is Bernoulli's principle that causes the air to flow faster."

Oh sure... and it is falling that causes gravity and losing that
causes cretins to buy lottery tickets.

As the other person said, your entertainment value is zero.

*plonk*

[Morgans[_2_]]

"BDS" > wrote
>
> Please do. Might I suggest you try a different approach when you ask
> someone for help?

Too late. Everyone knows that he is not worth the dynamite it would take to
blow him to H*ll and back.
--
Jim in NC

[Le Chaud Lapin]

On Oct 16, 11:04 am, "Androcles" > wrote:
> "Le Chaud Lapin" > wrote in
> : > In this video the air moves MUCH faster over the top of the wing
> : > than it does over the bottom:
> : > http://www.youtube.com/watch?v=KCcZyW-6-5o
> :
> : I just looked at this video.
> :
> : What you wrote and what this video demonstrates are two entirely
> : different things. There is no reason to say that the air moving above
> : the wing must meet beneath the wing.
>
> What do you think it meets, water?

BTW, there is nothing in that video about airplane wings. It only
shows Bernoulli's principle using smoke stacks, hanging balls, piece
of paper, etc. At no point do I see any demonstration of air above
and below having disparity in speed, unless you count the book.

-Le Chaud Lapin-

[Thomas]

On 16 Oct, 16:17, Le Chaud Lapin > wrote:
> On Oct 16, 6:31 am, Thomas > wrote:
>
>
>
> > On 9 Oct, 21:08, Le Chaud Lapin > wrote:
> > You may want to check out my web pageshttp://www.physicsmyths.org.uk/bernoulli.htm
> > andhttp://www.physicsmyths.org.uk/drag.htmfor a closer examination
> > of the physics behind the aerodynamic lift and drag.
>
> > The main point I am making there is that it is physically nonsense to
> > claim that changing merely the tangential velocity of the air stream
> > relative to the surface would in any way produce a resultant force (at
> > least for a non-viscous gas).
> > What one needs for a pressure change
> > (and thus a force) on the surface is a change in the numbers and/or
> > the velocity of the molecules hitting it, i.e. it is only the vertical
> > component of the velocity that is relevant here. Only this can produce
> > the lift for an airfoil, either because of the increased number of
> > collisions on the lower side or the decreased number of collisions on
> > the upper side (both situations lead to a lift).
>
> I agree, but there are some that seem to think the contrary, as you
> know, with the Coanda effect.http://en.wikipedia.org/wiki/Coand%C4%83_effect

The Coanda effect is only due to the viscosity of the gas/fluid and
thus would not appear for a non-viscous gas, but the aerodynamic lift
does (so the Coanda effect can not possibly be an instrumental cause
for the latter).

Based on the simple kinematical model for the change of the molecular
collision rates with the wing surface, one can indeed get a good
estimate for the lift of Boeing 747 for instance:

consider first a plate of a size 1 m^2 moving head-on with a velocity
of 250 m/s in air; air has a number density of about 10^25 molecules/
m^3 (at 10,000 m), so in 1 sec the plate will be hit by 10^25*250 =
2.5*10^27 molecules. If you assume that each molecule has a weight of
4.5*10^-26 kg, this means that the force on the plate is 2.5*10^27
*4.5*10^-26 *250 = 5.6*10^4 N = 12,600 lb. Of course, the wing surface
is not directly facing into the airstream but only at a very shallow
angle. Let's assume that this angle (the average slope of the upper
wing surface) is about 5 deg; this means that the force calculated
above has to be multiplied by a factor sin(5)*cos(5) to obtain the
lift and by a factor sin^2(5) to obtain the drag force, which results
in about 1,100 lb and 95 lb respectively. Now this would be for a wing
surface of 1m^2; however the total wing area of the Boeing 747 is 541
m^2 (see http://www.airliners.net/info/stats.main?id=100 ), so the
forces become about 600,000 lb for the lift and 50,000 lb for the drag
(by the wings). Note that this figure for the lift force is pretty
close to the maximum weight of a 747 (considering the crude nature of
the derivation, in particular the assumption of a 5 deg angle for the
slope of the upper wing surface).


> I just read both your web pages.
>
> BTW, your explanation of d'Alembert's Paradox and the blow-over-paper-
> attached-to-table experiment could both use diagrams. I am trying the
> blow over the paper experiment now and I am not sure if I am doing it
> as you described. Could you provide a more vivid description so I can
> make sure?

Well, the point is that the commonly given example with blowing over
the sheet of paper only works because (due to the orientation of the
paper surface) you are blowing away from the paper. The (on avarage)
initially stationary air molecules will thus be pulled with the air
molecules coming out of your mouth, i.e. away from the paper, which
will thus create a corresponding reduction of the number of molecules
near the paper surface, i.e. a pressure reduction. However, this all
can only happen a) because of the viscosity of the air (the molecules
coming out of your mouth collide with the air molecules, and b)
because you are blowing to a certain degree away from the paper. Would
you blow exactly parallel to the surface of a flat sheet of paper,
nothing would happen at all (it is obvious that if the sheet would
lift up at the 'downstream' end, it would be pushed right back again
into a position where the surface is parallel to the airstream (as
this is the force free equilibrium position)).

So since this effect (llike the Coanda effect) relies on the
viscosity of the air, it has nothing to do with the aerodynamic lift
(which also would occur if the air was completely inviscid).

Thomas

[Thomas]

On 16 Oct, 16:17, Le Chaud Lapin > wrote:
> On Oct 16, 6:31 am, Thomas > wrote:
>
>
>
> > On 9 Oct, 21:08, Le Chaud Lapin > wrote:
> > You may want to check out my web pageshttp://www.physicsmyths.org.uk/bernoulli.htm
> > andhttp://www.physicsmyths.org.uk/drag.htmfor a closer examination
> > of the physics behind the aerodynamic lift and drag.
>
> > The main point I am making there is that it is physically nonsense to
> > claim that changing merely the tangential velocity of the air stream
> > relative to the surface would in any way produce a resultant force (at
> > least for a non-viscous gas).
> > What one needs for a pressure change
> > (and thus a force) on the surface is a change in the numbers and/or
> > the velocity of the molecules hitting it, i.e. it is only the vertical
> > component of the velocity that is relevant here. Only this can produce
> > the lift for an airfoil, either because of the increased number of
> > collisions on the lower side or the decreased number of collisions on
> > the upper side (both situations lead to a lift).
>
> I agree, but there are some that seem to think the contrary, as you
> know, with the Coanda >effect.http://en.wikipedia.org/wiki/Coand%C4%83_effect
>
> What is troubling about many of these theories is that, at the precise
> moment where the reader is most alert in anticipation of the meat of
> the explanation, the hand-waving begins. In the link above, the clause
> entitled Causes, it is written:
>
> "The effect of a spoon apparently attracting a flow of water is caused
> by this effect as well, since the flow of water entrains gases to flow
> down along the stream, and these gases are then pulled, along with the
> flow of water, in towards the spoon, as a result of the pressure
> differential. "
>
> Hmmm...."and these gases are then pulled"...
>
> pulled? By what?


The Coanda effect is only due to the viscosity of the gas/fluid and
thus would not appear for a non-viscous gas, but the aerodynamic lift
does (so the Coanda effect can not possibly be an instrumental cause
for the latter).

Based on the simple kinematical model for the change of the molecular
collision rates with the wing surface, one can indeed get a good
estimate for the lift of Boeing 747 for instance:

consider first a plate of a size 1 m^2 moving head-on with a velocity
of 250 m/s in air; air has a number density of about 10^25 molecules/
m^3 (at 10,000 m), so in 1 sec the plate will be hit by 10^25*250 =
2.5*10^27 molecules. If you assume that each molecule has a weight of
4.5*10^-26 kg, this means that the force on the plate is 2*2.5*10^27
*4.5*10^-26 *250 = 5.6*10^4 N = 12,600 lb (the additional factor 2 is
due to the fact that in an elastic collision with the plate, the
momentum change is twice the momentum of the molecule). Of course, the
wing surface is not directly facing into the airstream but only at a
very shallow angle. Let's assume that this angle (the average slope of
the upper wing surface) is about 5 deg; this means that the force
calculated above has to be multiplied by a factor sin(5)*cos(5) to
obtain the lift and by a factor sin^2(5) to obtain the drag force,
which results in about 1,100 lb and 95 lb respectively. Now this would
be for a wing surface of 1m^2; however the total wing area of the
Boeing 747 is 541 m^2 (see http://www.airliners.net/info/stats.main?id=100
), so the forces become about 600,000 lb for the lift and 50,000 lb
for the drag (by the wings). Note that this figure for the lift force
is pretty close to the maximum weight of a 747 (considering the crude
nature of the derivation, in particular the assumption of a 5 deg
angle for the slope of the upper wing surface).

> > And it should be
> > obvious that for this to be the case, one must either have the lower
> > side of the wing facing to a certain degree into the airstream, and/or
> > the upper side facing to a certain degree opposite to the airstream.
> > This is why one either needs a certain 'angle of attack' or a
> > correspondingly shaped airfoil. And it should be obvious that in order
> > to have an asymmetric force (i.e. a higher upward than downward force)
> > one needs the surfaces of the airfoil to be orientated in some way
> > asymmetrical relatively to the airstream. So a perfectly symmetrical
> > airfoil (front to back) at a zero angle of attack (like I indicated in
> > Fig.1 on my pagehttp://www.physicsmyths.org.uk/bernoulli.htm) should
> > not produce any lift as the upward force (from the rear part) is
> > exactly equal to the downward force (from the front part). All that
> > would happen is that the wing experiences an anti-clockwise torque.
> > This is the reason why the rear part of the wing (behind the apex)
> > must always have a larger surface than the front part. At least I have
> > yet to see an airfoil where this is not the case and where it can be
> > used at a zero angle of attack.
> > (the Bernoulli principle is in direct contradiction to this as it
> > would also predict a lift for a perfectly symmetric airfoil in this
> > sense).
>
> I just read both your web pages.
>
> BTW, your explanation of d'Alembert's Paradox and the blow-over-paper-
> attached-to-table experiment could both use diagrams. I am trying the
> blow over the paper experiment now and I am not sure if I am doing it
> as you described. Could you provide a more vivid description so I can
> make sure?


Well, the point is that the commonly given example with blowing over
the sheet of paper only works because (due to the orientation of the
paper surface) you are blowing away from the paper. The (on avarage)
initially stationary air molecules will thus be pulled with the air
molecules coming out of your mouth, i.e. away from the paper, which
will thus create a corresponding reduction of the number of molecules
near the paper surface, i.e. a pressure reduction. However, this all
can only happen a) because of the viscosity of the air (the molecules
coming out of your mouth collide with the air molecules, and b)
because you are blowing to a certain degree away from the paper. Would
you blow exactly parallel to the surface of a flat sheet of paper,
nothing would happen at all (it is obvious that if the sheet would
lift up at the 'downstream' end, it would be pushed right back again
into a position where the surface is parallel to the airstream (as
this is the force free equilibrium position)).


So since this effect (llike the Coanda effect) relies on the
viscosity of the air, it has nothing to do with the aerodynamic lift
(which also would occur if the air was completely inviscid).

Thomas

[Thomas]

On 16 Oct, 18:29, Thomas > wrote:
> If you assume that each molecule has a weight of
> 4.5*10^-26 kg, this means that the force on the plate is 2.5*10^27
> *4.5*10^-26 *250 = 5.6*10^4 N = 12,600 lb. Of course, the wing

I forgot actually to write an additional factor 2 here which I added
because in an elastic collision with the plate, the momentum change is
twice the momentum of the molecule. So it should read:
"the force on the plate is 2*2.5*10^27 *4.5*10^-26 *250 = 5.6*10^4 N =
12,600 lb.

Thomas

[Jim Logajan]

Thomas > wrote:
> You may want to check out my web pages
> http://www.physicsmyths.org.uk/bernoulli.htm and
> http://www.physicsmyths.org.uk/drag.htm for a closer examination of
> the physics behind the aerodynamic lift and drag.

You might want to actually _include_ Bernoulli's theorem somewhere in your
pages. You talk about Bernoulli's equation, Bernoulli's principle, and
Bernoulli's law. And yet none of them are actually presented. Are you
saying they all the same or all different? Why not use the terminology used
by the professionals and stick with "Bernoulli's theorem"? How about
including references to relevant texts on your pages? It's not like serious
texts and lab experiments haven't been done on the subject for a zillion
years. It helps to show you know what you're talking about by showing
you've first read the professional literature on the subject and done your
own relevant research.

You might also want to redraw your figures so they include vertical labeled
arrows. Then present the assumptions and math needed to show your work and
why you think the vertical magnitudes sum to zero. Just saying they do, or
they only yield a torque, isn't good enough. It is more useful to _show_ -
not pontificate and hand-wave.

P.S. Chapter section 40-3 in volume 2 of Feynman's Lectures on Physics is
as good a place as any to start.

[Thomas]

On 16 Oct, 19:41, Jim Logajan > wrote:
> Thomas > wrote:
> > You may want to check out my web pages
> >http://www.physicsmyths.org.uk/bernoulli.htmand
> >http://www.physicsmyths.org.uk/drag.htm for a closer examination of
> > the physics behind the aerodynamic lift and drag.
>
> You might want to actually _include_ Bernoulli's theorem somewhere in your
> pages. You talk about Bernoulli's equation, Bernoulli's principle, and
> Bernoulli's law. And yet none of them are actually presented. Are you
> saying they all the same or all different? Why not use the terminology used
> by the professionals and stick with "Bernoulli's theorem"? How about
> including references to relevant texts on your pages? It's not like serious
> texts and lab experiments haven't been done on the subject for a zillion
> years. It helps to show you know what you're talking about by showing
> you've first read the professional literature on the subject and done your
> own relevant research.
>
> You might also want to redraw your figures so they include vertical labeled
> arrows. Then present the assumptions and math needed to show your work and
> why you think the vertical magnitudes sum to zero. Just saying they do, or
> they only yield a torque, isn't good enough. It is more useful to _show_ -
> not pontificate and hand-wave.
>
> P.S. Chapter section 40-3 in volume 2 of Feynman's Lectures on Physics is
> as good a place as any to start.

Bernoulli's theorem is not a fundamental physical law and thus not
required to understand the principle behind the aerodynamic lift. And
its misinterpretation and misapplication quite evidently leads to
incorrect physical conclusions, like the claim that a moving gas would
inherently have a lower static pressure than a stationary one. The net
flow velocity of a gas has per se nothing to do with the static
pressure.
As a thought experiment, consider a large tank containing gas with a
pipe attached to it which leads into a vacuum space. Assume first this
pipe is closed at the end; then the flow velocity in the pipe is zero
because the molecules heading outwards will be reflected at the end
and reverse their velocity (assume for simplicity that the molecules
do not collide with each other but only with the walls of the pipe and
the tank). If one now opens the pipe, the only thing that changes is
that the molecules heading outwards will not be reflected anymore at
the end but simply carry on heading into the vacuum space (with the
corresponding loss of molecules being replaced from the large tank).
So we now have a net flow velocity within the pipe without that either
the density nor the speed of the molecules has changed in any way.
This means that the pressure exerted on the inside wall of the pipe is
unchanged despite the fact that we now have a net flow velocity within
it. So Bernoulli's theorem would quite evidently give a wrong result
here.

Thomas

[Le Chaud Lapin]

On Oct 16, 3:31 pm, Thomas > wrote:
> On 16 Oct, 19:41, Jim Logajan > wrote:
>
>
>
>
>
> > Thomas > wrote:
> > > You may want to check out my web pages
> > >http://www.physicsmyths.org.uk/bernoulli.htmand
> > >http://www.physicsmyths.org.uk/drag.htmfor a closer examination of
> > > the physics behind the aerodynamic lift and drag.
>
> > You might want to actually _include_ Bernoulli's theorem somewhere in your
> > pages. You talk about Bernoulli's equation, Bernoulli's principle, and
> > Bernoulli's law. And yet none of them are actually presented. Are you
> > saying they all the same or all different? Why not use the terminology used
> > by the professionals and stick with "Bernoulli's theorem"? How about
> > including references to relevant texts on your pages? It's not like serious
> > texts and lab experiments haven't been done on the subject for a zillion
> > years. It helps to show you know what you're talking about by showing
> > you've first read the professional literature on the subject and done your
> > own relevant research.
>
> > You might also want to redraw your figures so they include vertical labeled
> > arrows. Then present the assumptions and math needed to show your work and
> > why you think the vertical magnitudes sum to zero. Just saying they do, or
> > they only yield a torque, isn't good enough. It is more useful to _show_ -
> > not pontificate and hand-wave.
>
> > P.S. Chapter section 40-3 in volume 2 of Feynman's Lectures on Physics is
> > as good a place as any to start.
>
> Bernoulli's theorem is not a fundamental physical law and thus not
> required to understand the principle behind the aerodynamic lift. And
> its misinterpretation and misapplication quite evidently leads to
> incorrect physical conclusions, like the claim that a moving gas would
> inherently have a lower static pressure than a stationary one. The net
> flow velocity of a gas has per se nothing to do with the static
> pressure.

I so agree. The amout of hand-waving that goes on when (presumably
technically-inclined) individuals invoke Bernoulli is perplexing.
Oddly, my college physics book is almost as guilty - after chapters
and chapters of Newtonian mechanics that are quite clear, they seem to
imply just that.

> As a thought experiment, consider a large tank containing gas with a
> pipe attached to it which leads into a vacuum space. Assume first this
> pipe is closed at the end; then the flow velocity in the pipe is zero
> because the molecules heading outwards will be reflected at the end
> and reverse their velocity (assume for simplicity that the molecules
> do not collide with each other but only with the walls of the pipe and
> the tank). If one now opens the pipe, the only thing that changes is
> that the molecules heading outwards will not be reflected anymore at
> the end but simply carry on heading into the vacuum space (with the
> corresponding loss of molecules being replaced from the large tank).
> So we now have a net flow velocity within the pipe without that either
> the density nor the speed of the molecules has changed in any way.
> This means that the pressure exerted on the inside wall of the pipe is
> unchanged despite the fact that we now have a net flow velocity within
> it. So Bernoulli's theorem would quite evidently give a wrong result
> here.

Hmmm...technically, someone could argue that, in the vicinity of the
exit hole of the tank, there would be resulting decrease in pressure,
which would be true.

The misapplication, I think, results from too much hand-waving and not
being very specific about what pressure decreases over what. A venturi
apparutus, for example, very clearly demonstrates a drop in pressure,
and that drop is real, but the points chosen to measure the pressure
in the apparutus is very specific.

-Le Chaud Lapin-

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
ups.com:

> On Oct 16, 10:20 am, "Androcles" > wrote:
>> "Le Chaud Lapin" > wrote in
>> oglegroups.com...
>> : On Oct 16, 3:47 am, "Androcles" > wrote:
>> : > "Le Chaud Lapin" > wrote in
>> glegroups.com...
>> : > : On Oct 15, 7:54 pm, "Androcles" >
>> : > : wrote:
>> : > : > "Le Chaud Lapin" > wrote in
>> : > messagenews:1192494448.158299.317200
@v23g2000prn.googlegroups.com.
>> : > ..
>> : > : > : On Oct 15, 6:42 pm, "Gatt" >
>> : > : > : wrote:
>> : > : > : > "Le Chaud Lapin" > wrote in
>> : > : > messagenews:1192488325.423647.30120
@i38g2000prf.googlegroups.c
>> : > : > om...
>> : > : > : >
>> : > : > : > > I read last night in another piloting book, again, that
>> : > : > : > > the
>> common
>> : > : > belief
>> : > : > : > > about the dynamics of airfoils is wrong,
>> : > : > : >
>> : > : > : > Yeah? Which one?
>> : > : > :
>> : > : > : I'd have to go back to bookstore to find the name.
>> : > : >
>> : > : > AHAHAHAHAHAHA!
>> : > : > Or back to sleep to dream again...
>> : > :
>> : > : Barry Schiff, in "The Proficient Pilot", "An AOPA Book", writes
>> : > : on page 2:
>> : > :
>> : > : "There is, for example, this amusing fable: "Air flowing above
>> : > : the wing has a greater distance to travel (because of camber)
>> : > : than air flowing beneath the wing. Therefore, air above the
>> : > : wing must travel faster so as to arrive at the wing's trailing
>> : > : edge at the same time as air flowing underneath. This is pure
>> : > : nonsense."
>> : >
>> : > Since it is true Schiff must be a raving lunatic. Maybe you don't
>> : > understand that travelling the greater path in the same time
>> : > involves a greater speed.
>> :
>> : Perhaps you could explain in detail what you mean by this last
>> : statement. I am sure that there are plenty of people here would
>> : would like, for once, that a pilot explains what s/he means by
>> : this.
>>
>> Really?
>> Ok, for plenty of cretins such as yourself...
>>
>> Travelling 70 miles (distance) in one hour (duration of time)
>> is a speed of 70 mph by definition.
>> 100 miles (the greater distance) in the same time (1 hour)
>> is 100 mph.
>> 100 mph is faster than 70 mph.
>> People unaware of this simple fact are prone to getting
>> speeding tickets and losing their license.
>> Aircraft pilots are even more aware of it than motorists,
>> using their stop watches to compute distance.
>
>> In this video the air moves MUCH faster over the top of the wing
>> than it does over the bottom:
>> http://www.youtube.com/watch?v=KCcZyW-6-5o
>
> I just looked at this video.
>
> What you wrote and what this video demonstrates are two entirely
> different things. There is no reason to say that the air moving above
> the wing must meet beneath the wing.
>
> I keep hearing people say,
>
> "The air moves faster, therefore Bernoulli's Principle must be
> invoked."
>
> The thesis of what I have been saying all along can be seeing in an
> inversion of this sentence.
>
> "It is Bernoulli's principle that causes the air to flow faster."
>
> In particular, it is the pressure gradient that causes the air in the
> contstriction to flow faster. This same pressure gradient exists
> above a wing in an air craft, and it has nothing to do with the
> distance traveled. The camber of the wing is carefully designed my
> airfcraft manufacturers to incudes, as much as possible, this pressure
> gradient, at a particular speed, but *with* the conflicting
> requirement that resulting drag must be reduced. This is why I said
> earlier that pressure at the front of the wing is not necessarily bad.
> It is desirable, but it also causes some laminar drag. Intuitively,
> one can see what the edge must not be made sharp - doing that would
> elimate the very pressure that is need to bring about the pressure
> gradient.
>
>> Now you can go back to sleep and dream of Barry Schiff and
>> his "nonsense".
>
> -Le Chaud Lapin-
>


Bad k00k! BAD!

Now shut up and go back in your box,


Bertie
>

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in news:1192554697.906337.44270
@v29g2000prd.googlegroups.com:

> On Oct 16, 11:04 am, "Androcles" > wrote:
>> "Le Chaud Lapin" > wrote in
>> : > In this video the air moves MUCH faster over the top of the wing
>> : > than it does over the bottom:
>> : > http://www.youtube.com/watch?v=KCcZyW-6-5o
>> :
>> : I just looked at this video.
>> :
>> : What you wrote and what this video demonstrates are two entirely
>> : different things. There is no reason to say that the air moving above
>> : the wing must meet beneath the wing.
>>
>> What do you think it meets, water?
>
> BTW, there is nothing in that video about airplane wings. It only
> shows Bernoulli's principle using smoke stacks, hanging balls, piece
> of paper, etc. At no point do I see any demonstration of air above
> and below having disparity in speed, unless you count the book.


Give it up Anthony. Nobody's buying.

Bertie

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
oups.com:

> On Oct 16, 9:53 am, "Gatt" > wrote:
>> > Barry Schiff, in "The Proficient Pilot", "An AOPA Book", writes on
>> > page 2:
>>
>> > "There is, for example, this amusing fable: "Air flowing above the
>> > wing has a greater distance to travel (because of camber) than air
>> > flowing beneath the wing. Therefore, air above the wing must travel
>> > faster so as to arrive at the wing's trailing edge at the same time
>> > as air flowing underneath. This is pure nonsense."
>>
>> Like I said. Upper camber is a conspiracy by the aluminum
>> manufacturers to sell more metal... Bournoulli was a shill.
>
> You wrote repeatedly that lack of attention to detail (mostly due to
> my spelling errors) indicated lack of understangind, was not becoming
> of a critical thinker, etc...yet you keep making spelling errors
> youself. :)
>
> I never disputed Bernoulli's Principle, not once. I said that there
> was a lot of hand-waving going on when pilots uttered greater/lesser/
> camber/Bernoulli in the same sentence.
>
> Bernoulli's principle is correct.
>
> That the camber influences lift is correct.
>
> But how the camber influences lift has nothing to do with greater
> distances traveled, IMO.
>


Guess what, Your opinion is worthless.

you don;t fly and you never will, so bernoulli wil never be your slave..




M
Bertie

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
oups.com:

> On Oct 16, 3:31 pm, Thomas > wrote:
>> On 16 Oct, 19:41, Jim Logajan > wrote:
>>
>>
>>
>>
>>
>> > Thomas > wrote:
>> > > You may want to check out my web pages
>> > >http://www.physicsmyths.org.uk/bernoulli.htmand
>> > >http://www.physicsmyths.org.uk/drag.htmfor a closer examination of
>> > > the physics behind the aerodynamic lift and drag.
>>
>> > You might want to actually _include_ Bernoulli's theorem somewhere
>> > in your pages. You talk about Bernoulli's equation, Bernoulli's
>> > principle, and Bernoulli's law. And yet none of them are actually
>> > presented. Are you saying they all the same or all different? Why
>> > not use the terminology used by the professionals and stick with
>> > "Bernoulli's theorem"? How about including references to relevant
>> > texts on your pages? It's not like serious texts and lab
>> > experiments haven't been done on the subject for a zillion years.
>> > It helps to show you know what you're talking about by showing
>> > you've first read the professional literature on the subject and
>> > done your own relevant research.
>>
>> > You might also want to redraw your figures so they include vertical
>> > labeled arrows. Then present the assumptions and math needed to
>> > show your work and why you think the vertical magnitudes sum to
>> > zero. Just saying they do, or they only yield a torque, isn't good
>> > enough. It is more useful to _show_ - not pontificate and
>> > hand-wave.
>>
>> > P.S. Chapter section 40-3 in volume 2 of Feynman's Lectures on
>> > Physics is as good a place as any to start.
>>
>> Bernoulli's theorem is not a fundamental physical law and thus not
>> required to understand the principle behind the aerodynamic lift. And
>> its misinterpretation and misapplication quite evidently leads to
>> incorrect physical conclusions, like the claim that a moving gas
>> would inherently have a lower static pressure than a stationary one.
>> The net flow velocity of a gas has per se nothing to do with the
>> static pressure.
>
> I so agree. The amout of hand-waving that goes on when (presumably
> technically-inclined) individuals invoke Bernoulli is perplexing.
> Oddly, my college physics book is almost as guilty - after chapters
> and chapters of Newtonian mechanics that are quite clear, they seem to
> imply just that.
>
>> As a thought experiment, consider a large tank containing gas with a
>> pipe attached to it which leads into a vacuum space. Assume first
>> this pipe is closed at the end; then the flow velocity in the pipe is
>> zero because the molecules heading outwards will be reflected at the
>> end and reverse their velocity (assume for simplicity that the
>> molecules do not collide with each other but only with the walls of
>> the pipe and the tank). If one now opens the pipe, the only thing
>> that changes is that the molecules heading outwards will not be
>> reflected anymore at the end but simply carry on heading into the
>> vacuum space (with the corresponding loss of molecules being replaced
>> from the large tank). So we now have a net flow velocity within the
>> pipe without that either the density nor the speed of the molecules
>> has changed in any way. This means that the pressure exerted on the
>> inside wall of the pipe is unchanged despite the fact that we now
>> have a net flow velocity within it. So Bernoulli's theorem would
>> quite evidently give a wrong result here.
>
> Hmmm...technically, someone could argue that, in the vicinity of the
> exit hole of the tank, there would be resulting decrease in pressure,
> which would be true.
>
> The misapplication, I think, results from too much hand-waving and not
> being very specific about what pressure decreases over what. A venturi
> apparutus, for example, very clearly demonstrates a drop in pressure,
> and that drop is real, but the points chosen to measure the pressure
> in the apparutus is very specific.
>

Hey, i'm waving my hand!

Well, just one finger, to be precise..


Bertie

[Bertie the Bunyip[_19_]]

"Morgans" > wrote in
:

>
> "Bertie the Bunyip" > wrote
>
>>
>> What's it matter? Yo'll never be a pilot. Any math that wil enable
>> you to dial up for home delivered pizza and escargot should suffice.
>> #
>
> Are you kidding? He doesn't have a job to provide enough money for
> escargot.
>
> The only escargot he is going to see is from the snails he plucks out
> of the river!
>
> Mmmmmm!


Nah, they're cheap enough in France.

They sell 'em on the streets for about $2 a bag. I can speak on this with
some authority, BTW, since that's where I am today and I seen some for
sale.



Bertie

[Bertie the Bunyip[_19_]]

Le Chaud Lapin > wrote in
ups.com:

> On Oct 16, 6:31 am, Thomas > wrote:
>> On 9 Oct, 21:08, Le Chaud Lapin > wrote:
>> You may want to check out my web
>> pageshttp://www.physicsmyths.org.uk/bernoulli.htm
>> andhttp://www.physicsmyths.org.uk/drag.htm for a closer examination
>> of the physics behind the aerodynamic lift and drag.
>>
>> The main point I am making there is that it is physically nonsense to
>> claim that changing merely the tangential velocity of the air stream
>> relative to the surface would in any way produce a resultant force
>> (at least for a non-viscous gas).
>
>> What one needs for a pressure change
>> (and thus a force) on the surface is a change in the numbers and/or
>> the velocity of the molecules hitting it, i.e. it is only the
>> vertical component of the velocity that is relevant here. Only this
>> can produce the lift for an airfoil, either because of the increased
>> number of collisions on the lower side or the decreased number of
>> collisions on the upper side (both situations lead to a lift).
>
> I agree, but there are some that seem to think the contrary, as you
> know, with the Coanda effect.
> http://en.wikipedia.org/wiki/Coand%C4%83_effect
>
> What is troubling about many of these theories is that, at the precise
> moment where the reader is most alert in anticipation of the meat of
> the explanation, the hand-waving begins. In the link above, the clause
> entitled Causes, it is written:
>
> "The effect of a spoon apparently attracting a flow of water is caused
> by this effect as well, since the flow of water entrains gases to flow
> down along the stream, and these gases are then pulled, along with the
> flow of water, in towards the spoon, as a result of the pressure
> differential. "
>
> Hmmm...."and these gases are then pulled"...
>
> pulled? By what?
>
>> And it should be
>> obvious that for this to be the case, one must either have the lower
>> side of the wing facing to a certain degree into the airstream,
>> and/or the upper side facing to a certain degree opposite to the
>> airstream. This is why one either needs a certain 'angle of attack'
>> or a correspondingly shaped airfoil. And it should be obvious that in
>> order to have an asymmetric force (i.e. a higher upward than downward
>> force) one needs the surfaces of the airfoil to be orientated in some
>> way asymmetrical relatively to the airstream. So a perfectly
>> symmetrical airfoil (front to back) at a zero angle of attack (like I
>> indicated in Fig.1 on my
>> pagehttp://www.physicsmyths.org.uk/bernoulli.htm) should not produce
>> any lift as the upward force (from the rear part) is exactly equal to
>> the downward force (from the front part). All that would happen is
>> that the wing experiences an anti-clockwise torque. This is the
>> reason why the rear part of the wing (behind the apex) must always
>> have a larger surface than the front part. At least I have yet to see
>> an airfoil where this is not the case and where it can be used at a
>> zero angle of attack. (the Bernoulli principle is in direct
>> contradiction to this as it would also predict a lift for a perfectly
>> symmetric airfoil in this sense).
>
> I just read both your web pages.
>
> BTW, your explanation of d'Alembert's Paradox and the blow-over-paper-
> attached-to-table experiment could both use diagrams. I am trying the
> blow over the paper experiment now and I am not sure if I am doing it
> as you described. Could you provide a more vivid description so I can
> make sure?
>


MAybe if you took your head out of your ass first..

Bertie

[Morgans[_2_]]

"Bertie the Bunyip" > wrote

> MAybe if you took your head out of your ass first..

Or bend over, and blow it up your ass.
--
Jim in NC

[ManhattanMan]

Morgans wrote:
> "Bertie the Bunyip" > wrote
>
>> MAybe if you took your head out of your ass first..
>
> Or bend over, and blow it up your ass.

Well, damn! He did it!!!!!!!!!!!!

http://www.members.cox.net/drpics/hua2.jpg

[Mxsmanic]

BDS writes:

> Please do. Might I suggest you try a different approach when you ask
> someone for help?

Like genuflection?

[Mxsmanic]

Le Chaud Lapin writes:

> What about my orignial post is abrasive and insulting?

You refused to submit to the alpha dog and his pack.

[Bertie the Bunyip[_19_]]

Mxsmanic > wrote in
:

> BDS writes:
>
>> Please do. Might I suggest you try a different approach when you ask
>> someone for help?
>
> Like genuflection?
>

Or you could just kiss my ring.


Bertie

[Bertie the Bunyip[_19_]]

Mxsmanic > wrote in
:

> Le Chaud Lapin writes:
>
>> What about my orignial post is abrasive and insulting?
>
> You refused to submit to the alpha dog and his pack.

God I love usenet.


Bertie

[Thomas]

On 17 Oct, 00:48, Le Chaud Lapin > wrote:
> On Oct 16, 3:31 pm, Thomas > wrote:
>
>
>
> > On 16 Oct, 19:41, Jim Logajan > wrote:
>
> > > Thomas > wrote:
> > > > You may want to check out my web pages
> > > >http://www.physicsmyths.org.uk/bernoulli.htmand
> > > >http://www.physicsmyths.org.uk/drag.htmfora closer examination of
> > > > the physics behind the aerodynamic lift and drag.
>
> > > You might want to actually _include_ Bernoulli's theorem somewhere in your
> > > pages. You talk about Bernoulli's equation, Bernoulli's principle, and
> > > Bernoulli's law. And yet none of them are actually presented. Are you
> > > saying they all the same or all different? Why not use the terminology used
> > > by the professionals and stick with "Bernoulli's theorem"? How about
> > > including references to relevant texts on your pages? It's not like serious
> > > texts and lab experiments haven't been done on the subject for a zillion
> > > years. It helps to show you know what you're talking about by showing
> > > you've first read the professional literature on the subject and done your
> > > own relevant research.
>
> > > You might also want to redraw your figures so they include vertical labeled
> > > arrows. Then present the assumptions and math needed to show your work and
> > > why you think the vertical magnitudes sum to zero. Just saying they do, or
> > > they only yield a torque, isn't good enough. It is more useful to _show_ -
> > > not pontificate and hand-wave.
>
> > > P.S. Chapter section 40-3 in volume 2 of Feynman's Lectures on Physics is
> > > as good a place as any to start.
>
> > Bernoulli's theorem is not a fundamental physical law and thus not
> > required to understand the principle behind the aerodynamic lift. And
> > its misinterpretation and misapplication quite evidently leads to
> > incorrect physical conclusions, like the claim that a moving gas would
> > inherently have a lower static pressure than a stationary one. The net
> > flow velocity of a gas has per se nothing to do with the static
> > pressure.
>
> I so agree. The amout of hand-waving that goes on when (presumably
> technically-inclined) individuals invoke Bernoulli is perplexing.
> Oddly, my college physics book is almost as guilty - after chapters
> and chapters of Newtonian mechanics that are quite clear, they seem to
> imply just that.

It is not so much a case of 'hand waving' arguments, but of
insufficient and contradictory physical definitions (especially with
regard to the notion of an 'inviscid' gas). Applying some physical
equation to a situation where it can not be applied is bound to lead
to paradoxes and wrong results.

>
>
>
> > As a thought experiment, consider a large tank containing gas with a
> > pipe attached to it which leads into a vacuum space. Assume first this
> > pipe is closed at the end; then the flow velocity in the pipe is zero
> > because the molecules heading outwards will be reflected at the end
> > and reverse their velocity (assume for simplicity that the molecules
> > do not collide with each other but only with the walls of the pipe and
> > the tank). If one now opens the pipe, the only thing that changes is
> > that the molecules heading outwards will not be reflected anymore at
> > the end but simply carry on heading into the vacuum space (with the
> > corresponding loss of molecules being replaced from the large tank).
> > So we now have a net flow velocity within the pipe without that either
> > the density nor the speed of the molecules has changed in any way.
> > This means that the pressure exerted on the inside wall of the pipe is
> > unchanged despite the fact that we now have a net flow velocity within
> > it. So Bernoulli's theorem would quite evidently give a wrong result
> > here.
>
> Hmmm...technically, someone could argue that, in the vicinity of the
> exit hole of the tank, there would be resulting decrease in pressure,
> which would be true.

As should be evident from what I said above already, for an inviscid
gas (i.e. assuming the molecules do not collide with each other but
only with the walls), it should not make any difference whatsoever if
the pipe is open or closed at the end. The rate with which the
molecules hit the inside wall (and thus the pressure on it) is exactly
the same anywhere within the pipe (assuming the lost molecules for the
open pipe situation are readily replaced from the tank).

>
> The misapplication, I think, results from too much hand-waving and not
> being very specific about what pressure decreases over what. A venturi
> apparutus, for example, very clearly demonstrates a drop in pressure,
> and that drop is real, but the points chosen to measure the pressure
> in the apparutus is very specific.

The Venturi effect (like the paper sheet example, the Coanda effect
and the Magnus effect) is merely a result of the viscosity of the
medium. It does not occur for an ideally inviscid medium (i.e. if the
collisions of molecules amongst each other can be neglected), whereas
the aerodynamic lift does.

Thomas

[BDS]

"Mxsmanic" > wrote in message
...
> Le Chaud Lapin writes:
>
> > What about my orignial post is abrasive and insulting?
>
> You refused to submit to the alpha dog and his pack.

What, no blame for the angry young males that incessantly torment you?

BDS

[BDS]

"Mxsmanic" > wrote in message
...
> BDS writes:
>
> > Please do. Might I suggest you try a different approach when you ask
> > someone for help?
>
> Like genuflection?

Funny that you and Bugs seem to be the only ones with this problem.

Maybe it's not a problem with the group...

BDS

[jon]

On 11 Okt, 22:49, "Androcles" > wrote:
> "CWatters" > wrote in message
>
> ...
> :
> : "mike regish" > wrote in message
> ...
> : > I think that the shape of the wing simply allows for a greater range of
> : > angles of attack. A sheet of plywood would providelift, but only at a
> : very
> : > precise and small angle of attack.
> : >
> : > The airfoil shape allows the wing to
> : > provideliftthrough a much larger range of angles of attack.
> :
> : Well sort of.
> :
> : Thick wings do tend to operate over a wider range of angles than thin
> wings
> : but most subsonic wing sections will work from 0 to 10 degrees or more.
> It's
> : above 12 or 15 degrees that the section becomes more critical.
> :
> : A conventional wing section with camber can produce +veliftat zero
> degrees
> : AOA.
> :
> : The zeroliftangle (the angle at which noliftis produced) is actually
> : negative on many conventional sections.
>
> Ever heard ofBernoulli?
> Try this demonstration:
> http://www.youtube.com/watch?v=KCcZyW-6-5o
> A Tomahawk cruise missile uses its wings as a control surface more
> than forlift. Straight and level is useful for the computer programmer.
> He thinks that way.
> http://www.youtube.com/watch?v=19XXTArAGaM


All aircraft fly due to wings Angle of Attack (AOA).

All new airliners have supercritical wings and these wings have a
almost upper surface.


This web shows the vertical downwash from heavy jets, on landing at
London/Gatwick.

http://www.efluids.com/efluids/gallery/gallery_pages/1plane_page.jsp

There are more of them att http://airteamimages.com/ search London/
Gatwick final

Before these pictures we only had the Cessna Citation flying over the
fog, making downwash grave.

[Androcles]

"jon" > wrote in message
ups.com...
: On 11 Okt, 22:49, "Androcles" > wrote:
: > "CWatters" > wrote in message
: >
: > ...
: > :
: > : "mike regish" > wrote in message
: > ...
: > : > I think that the shape of the wing simply allows for a greater range
of
: > : > angles of attack. A sheet of plywood would providelift, but only at
a
: > : very
: > : > precise and small angle of attack.
: > : >
: > : > The airfoil shape allows the wing to
: > : > provideliftthrough a much larger range of angles of attack.
: > :
: > : Well sort of.
: > :
: > : Thick wings do tend to operate over a wider range of angles than thin
: > wings
: > : but most subsonic wing sections will work from 0 to 10 degrees or
more.
: > It's
: > : above 12 or 15 degrees that the section becomes more critical.
: > :
: > : A conventional wing section with camber can produce +veliftat zero
: > degrees
: > : AOA.
: > :
: > : The zeroliftangle (the angle at which noliftis produced) is actually
: > : negative on many conventional sections.
: >
: > Ever heard ofBernoulli?
: > Try this demonstration:
: > http://www.youtube.com/watch?v=KCcZyW-6-5o
: > A Tomahawk cruise missile uses its wings as a control surface more
: > than forlift. Straight and level is useful for the computer programmer.
: > He thinks that way.
: > http://www.youtube.com/watch?v=19XXTArAGaM
:
:
: All aircraft fly due to wings Angle of Attack (AOA).

Tell it to a bumble bee (BB).

[Bertie the Bunyip[_19_]]

jon > wrote in
ups.com:

> On 11 Okt, 22:49, "Androcles" > wrote:
>> "CWatters" > wrote in message
>>
>> ...
>> :
>> : "mike regish" > wrote in message
>> ...
>> : > I think that the shape of the wing simply allows for a greater
>> : > range of angles of attack. A sheet of plywood would providelift,
>> : > but only at a
>> : very
>> : > precise and small angle of attack.
>> : >
>> : > The airfoil shape allows the wing to
>> : > provideliftthrough a much larger range of angles of attack.
>> :
>> : Well sort of.
>> :
>> : Thick wings do tend to operate over a wider range of angles than
>> : thin
>> wings
>> : but most subsonic wing sections will work from 0 to 10 degrees or
>> : more.
>> It's
>> : above 12 or 15 degrees that the section becomes more critical.
>> :
>> : A conventional wing section with camber can produce +veliftat zero
>> degrees
>> : AOA.
>> :
>> : The zeroliftangle (the angle at which noliftis produced) is
>> : actually negative on many conventional sections.
>>
>> Ever heard ofBernoulli?
>> Try this demonstration:
>> http://www.youtube.com/watch?v=KCcZyW-6-5o
>> A Tomahawk cruise missile uses its wings as a control surface more
>> than forlift. Straight and level is useful for the computer
>> programmer. He thinks that way.
>> http://www.youtube.com/watch?v=19XXTArAGaM
>
>
> All aircraft fly due to wings Angle of Attack (AOA).
>
> All new airliners have supercritical wings and these wings have a
> almost upper surface.
>
>
> This web shows the vertical downwash from heavy jets, on landing at
> London/Gatwick.
>
> http://www.efluids.com/efluids/gallery/gallery_pages/1plane_page.jsp
>
> There are more of them att http://airteamimages.com/ search London/
> Gatwick final
>
> Before these pictures we only had the Cessna Citation flying over the
> fog, making downwash grave.
>
>

Nope, not downwash, wake vortices,
and in fact this one nicely shows the low pressure causing fog on the
top of the wing...



http://www.efluids.com/efluids/gallery/gallery_pages/Morris_8.jsp



Bertie

[Bertie the Bunyip[_19_]]

Thomas > wrote in
oups.com:

> On 17 Oct, 00:48, Le Chaud Lapin > wrote:
>> On Oct 16, 3:31 pm, Thomas > wrote:
>>
>>
>>
>> > On 16 Oct, 19:41, Jim Logajan > wrote:
>>
>> > > Thomas > wrote:
>> > > > You may want to check out my web pages
>> > > >http://www.physicsmyths.org.uk/bernoulli.htmand
>> > > >http://www.physicsmyths.org.uk/drag.htmfora closer examination
>> > > >of
>> > > > the physics behind the aerodynamic lift and drag.
>>
>> > > You might want to actually _include_ Bernoulli's theorem
>> > > somewhere in your pages. You talk about Bernoulli's equation,
>> > > Bernoulli's principle, and Bernoulli's law. And yet none of them
>> > > are actually presented. Are you saying they all the same or all
>> > > different? Why not use the terminology used by the professionals
>> > > and stick with "Bernoulli's theorem"? How about including
>> > > references to relevant texts on your pages? It's not like serious
>> > > texts and lab experiments haven't been done on the subject for a
>> > > zillion years. It helps to show you know what you're talking
>> > > about by showing you've first read the professional literature on
>> > > the subject and done your own relevant research.
>>
>> > > You might also want to redraw your figures so they include
>> > > vertical labeled arrows. Then present the assumptions and math
>> > > needed to show your work and why you think the vertical
>> > > magnitudes sum to zero. Just saying they do, or they only yield a
>> > > torque, isn't good enough. It is more useful to _show_ - not
>> > > pontificate and hand-wave.
>>
>> > > P.S. Chapter section 40-3 in volume 2 of Feynman's Lectures on
>> > > Physics is as good a place as any to start.
>>
>> > Bernoulli's theorem is not a fundamental physical law and thus not
>> > required to understand the principle behind the aerodynamic lift.
>> > And its misinterpretation and misapplication quite evidently leads
>> > to incorrect physical conclusions, like the claim that a moving gas
>> > would inherently have a lower static pressure than a stationary
>> > one. The net flow velocity of a gas has per se nothing to do with
>> > the static pressure.
>>
>> I so agree. The amout of hand-waving that goes on when (presumably
>> technically-inclined) individuals invoke Bernoulli is perplexing.
>> Oddly, my college physics book is almost as guilty - after chapters
>> and chapters of Newtonian mechanics that are quite clear, they seem
>> to imply just that.
>
> It is not so much a case of 'hand waving' arguments, but of
> insufficient and contradictory physical definitions (especially with
> regard to the notion of an 'inviscid' gas). Applying some physical
> equation to a situation where it can not be applied is bound to lead
> to paradoxes and wrong results.
>
>>
>>
>>
>> > As a thought experiment, consider a large tank containing gas with
>> > a pipe attached to it which leads into a vacuum space. Assume first
>> > this pipe is closed at the end; then the flow velocity in the pipe
>> > is zero because the molecules heading outwards will be reflected at
>> > the end and reverse their velocity (assume for simplicity that the
>> > molecules do not collide with each other but only with the walls of
>> > the pipe and the tank). If one now opens the pipe, the only thing
>> > that changes is that the molecules heading outwards will not be
>> > reflected anymore at the end but simply carry on heading into the
>> > vacuum space (with the corresponding loss of molecules being
>> > replaced from the large tank). So we now have a net flow velocity
>> > within the pipe without that either the density nor the speed of
>> > the molecules has changed in any way. This means that the pressure
>> > exerted on the inside wall of the pipe is unchanged despite the
>> > fact that we now have a net flow velocity within it. So Bernoulli's
>> > theorem would quite evidently give a wrong result here.
>>
>> Hmmm...technically, someone could argue that, in the vicinity of the
>> exit hole of the tank, there would be resulting decrease in pressure,
>> which would be true.
>
> As should be evident from what I said above already, for an inviscid
> gas (i.e. assuming the molecules do not collide with each other but
> only with the walls), it should not make any difference whatsoever if
> the pipe is open or closed at the end. The rate with which the
> molecules hit the inside wall (and thus the pressure on it) is exactly
> the same anywhere within the pipe (assuming the lost molecules for the
> open pipe situation are readily replaced from the tank).
>
>>
>> The misapplication, I think, results from too much hand-waving and
>> not being very specific about what pressure decreases over what. A
>> venturi apparutus, for example, very clearly demonstrates a drop in
>> pressure, and that drop is real, but the points chosen to measure the
>> pressure in the apparutus is very specific.
>
> The Venturi effect (like the paper sheet example, the Coanda effect
> and the Magnus effect) is merely a result of the viscosity of the
> medium. It does not occur for an ideally inviscid medium (i.e. if the
> collisions of molecules amongst each other can be neglected), whereas
> the aerodynamic lift does.

Jesus Christ you're boring.

You want to have something done about that.

Oh yes, also, you;re wrong.


Bertie

[Bertie the Bunyip[_19_]]

"BDS" > wrote in news:WYkRi.60257$YL5.53077
@newssvr29.news.prodigy.net:

>
> "Mxsmanic" > wrote in message
> ...
>> Le Chaud Lapin writes:
>>
>> > What about my orignial post is abrasive and insulting?
>>
>> You refused to submit to the alpha dog and his pack.
>
> What, no blame for the angry young males that incessantly torment you?


We're such bullies. We should be so ashamed.

Bertie

[Mxsmanic]

BDS writes:

> What, no blame for the angry young males that incessantly torment you?

I simply used a synonym.

[Mxsmanic]

BDS writes:

> Funny that you and Bugs seem to be the only ones with this problem.
>
> Maybe it's not a problem with the group...

Or maybe it is.

[Mxsmanic]

Androcles writes:

> Tell it to a bumble bee (BB).

Bees are not aircraft.

[Bertie the Bunyip[_19_]]

Mxsmanic > wrote in
:

> Androcles writes:
>
>> Tell it to a bumble bee (BB).
>
> Bees are not aircraft.
>

Yes, they are, fjukwit.


They certainly do more flying than you do.

But then, so do pigs.



Bertie

[Bertie the Bunyip[_19_]]

Mxsmanic > wrote in
:

> BDS writes:
>
>> Funny that you and Bugs seem to be the only ones with this problem.
>>
>> Maybe it's not a problem with the group...
>
> Or maybe it is.
>

Nope.

Bertie

[Bertie the Bunyip[_19_]]

Mxsmanic > wrote in
:

> BDS writes:
>
>> What, no blame for the angry young males that incessantly torment you?
>
> I simply used a synonym.
>


No, you didn't


Bertie

[jon]

On 17 Okt, 03:03, Bertie the Bunyip > wrote:
> Le Chaud Lapin > wrote roups.com:
>
>
>
>
>
> > On Oct 16, 6:31 am, Thomas > wrote:
> >> On 9 Oct, 21:08, Le Chaud Lapin > wrote:
> >> You may want to check out my web
> >> pageshttp://www.physicsmyths.org.uk/bernoulli.htm
> >> andhttp://www.physicsmyths.org.uk/drag.htmfor a closer examination
> >> of the physics behind the aerodynamicliftand drag.
>
> >> The main point I am making there is that it is physically nonsense to
> >> claim that changing merely the tangential velocity of the air stream
> >> relative to the surface would in any way produce a resultant force
> >> (at least for a non-viscous gas).
>
> >> What one needs for a pressure change
> >> (and thus a force) on the surface is a change in the numbers and/or
> >> the velocity of the molecules hitting it, i.e. it is only the
> >> vertical component of the velocity that is relevant here. Only this
> >> can produce theliftfor an airfoil, either because of the increased
> >> number of collisions on the lower side or the decreased number of
> >> collisions on the upper side (both situations lead to alift).
>
> > I agree, but there are some that seem to think the contrary, as you
> > know, with the Coanda effect.
> >http://en.wikipedia.org/wiki/Coand%C4%83_effect
>
> > What is troubling about many of these theories is that, at the precise
> > moment where the reader is most alert in anticipation of the meat of
> > the explanation, the hand-waving begins. In the link above, the clause
> > entitled Causes, it is written:
>
> > "The effect of a spoon apparently attracting a flow of water is caused
> > by this effect as well, since the flow of water entrains gases to flow
> > down along the stream, and these gases are then pulled, along with the
> > flow of water, in towards the spoon, as a result of the pressure
> > differential. "
>
> > Hmmm...."and these gases are then pulled"...
>
> > pulled? By what?
>
> >> And it should be
> >> obvious that for this to be the case, one must either have the lower
> >> side of the wing facing to a certain degree into the airstream,
> >> and/or the upper side facing to a certain degree opposite to the
> >> airstream. This is why one either needs a certain 'angle of attack'
> >> or a correspondingly shaped airfoil. And it should be obvious that in
> >> order to have an asymmetric force (i.e. a higher upward than downward
> >> force) one needs the surfaces of the airfoil to be orientated in some
> >> way asymmetrical relatively to the airstream. So a perfectly
> >> symmetrical airfoil (front to back) at a zero angle of attack (like I
> >> indicated in Fig.1 on my
> >> pagehttp://www.physicsmyths.org.uk/bernoulli.htm) should not produce
> >> anyliftas the upward force (from the rear part) is exactly equal to
> >> the downward force (from the front part). All that would happen is
> >> that the wing experiences an anti-clockwise torque. This is the
> >> reason why the rear part of the wing (behind the apex) must always
> >> have a larger surface than the front part. At least I have yet to see
> >> an airfoil where this is not the case and where it can be used at a
> >> zero angle of attack. (theBernoulliprinciple is in direct
> >> contradiction to this as it would also predict aliftfor a perfectly
> >> symmetric airfoil in this sense).
>
> > I just read both your web pages.
>
> > BTW, your explanation of d'Alembert's Paradox and the blow-over-paper-
> > attached-to-table experiment could both use diagrams. I am trying the
> > blow over the paper experiment now and I am not sure if I am doing it
> > as you described. Could you provide a more vivid description so I can
> > make sure?
>
> MAybe if you took your head out of your ass first..
>
> Bertie- Dölj citerad text -
>
> - Visa citerad text -

But Bertie, you were considered to be an idiot, already 3 years ago.

You seems not to have improved!

Here you see the vertical airflow due to wings AOA and downwash from a
heavy jet:

http://www.efluids.com/efluids/gallery/gallery_pages/Morris_4.jsp

[Bertie the Bunyip[_19_]]

jon > wrote in
ups.com:

> On 17 Okt, 03:03, Bertie the Bunyip > wrote:
>> Le Chaud Lapin > wrote
>> innews:1192547842.109495.1581
> :
>>
>>
>>
>>
>>
>> > On Oct 16, 6:31 am, Thomas > wrote:
>> >> On 9 Oct, 21:08, Le Chaud Lapin > wrote:
>> >> You may want to check out my web
>> >> pageshttp://www.physicsmyths.org.uk/bernoulli.htm
>> >> andhttp://www.physicsmyths.org.uk/drag.htmfor a closer examination
>> >> of the physics behind the aerodynamicliftand drag.
>>
>> >> The main point I am making there is that it is physically nonsense
>> >> to claim that changing merely the tangential velocity of the air
>> >> stream relative to the surface would in any way produce a
>> >> resultant force (at least for a non-viscous gas).
>>
>> >> What one needs for a pressure change
>> >> (and thus a force) on the surface is a change in the numbers
>> >> and/or the velocity of the molecules hitting it, i.e. it is only
>> >> the vertical component of the velocity that is relevant here. Only
>> >> this can produce theliftfor an airfoil, either because of the
>> >> increased number of collisions on the lower side or the decreased
>> >> number of collisions on the upper side (both situations lead to
>> >> alift).
>>
>> > I agree, but there are some that seem to think the contrary, as you
>> > know, with the Coanda effect.
>> >http://en.wikipedia.org/wiki/Coand%C4%83_effect
>>
>> > What is troubling about many of these theories is that, at the
>> > precise moment where the reader is most alert in anticipation of
>> > the meat of the explanation, the hand-waving begins. In the link
>> > above, the clause entitled Causes, it is written:
>>
>> > "The effect of a spoon apparently attracting a flow of water is
>> > caused by this effect as well, since the flow of water entrains
>> > gases to flow down along the stream, and these gases are then
>> > pulled, along with the flow of water, in towards the spoon, as a
>> > result of the pressure differential. "
>>
>> > Hmmm...."and these gases are then pulled"...
>>
>> > pulled? By what?
>>
>> >> And it should be
>> >> obvious that for this to be the case, one must either have the
>> >> lower side of the wing facing to a certain degree into the
>> >> airstream, and/or the upper side facing to a certain degree
>> >> opposite to the airstream. This is why one either needs a certain
>> >> 'angle of attack' or a correspondingly shaped airfoil. And it
>> >> should be obvious that in order to have an asymmetric force (i.e.
>> >> a higher upward than downward force) one needs the surfaces of the
>> >> airfoil to be orientated in some way asymmetrical relatively to
>> >> the airstream. So a perfectly symmetrical airfoil (front to back)
>> >> at a zero angle of attack (like I indicated in Fig.1 on my
>> >> pagehttp://www.physicsmyths.org.uk/bernoulli.htm) should not
>> >> produce anyliftas the upward force (from the rear part) is exactly
>> >> equal to the downward force (from the front part). All that would
>> >> happen is that the wing experiences an anti-clockwise torque. This
>> >> is the reason why the rear part of the wing (behind the apex) must
>> >> always have a larger surface than the front part. At least I have
>> >> yet to see an airfoil where this is not the case and where it can
>> >> be used at a zero angle of attack. (theBernoulliprinciple is in
>> >> direct contradiction to this as it would also predict aliftfor a
>> >> perfectly symmetric airfoil in this sense).
>>
>> > I just read both your web pages.
>>
>> > BTW, your explanation of d'Alembert's Paradox and the
>> > blow-over-paper- attached-to-table experiment could both use
>> > diagrams. I am trying the blow over the paper experiment now and I
>> > am not sure if I am doing it as you described. Could you provide a
>> > more vivid description so I can make sure?
>>
>> MAybe if you took your head out of your ass first..
>>
>> Bertie- Dölj citerad text -
>>
>> - Visa citerad text -
>
> But Bertie, you were considered to be an idiot, already 3 years ago.
>
> You seems not to have improved!
>
> Here you see the vertical airflow due to wings AOA and downwash from a
> heavy jet:
>
> http://www.efluids.com/efluids/gallery/gallery_pages/Morris_4.jsp
>



Oh goodie, it's the huigh priest of fjukktardedeness, Jon.


He that would argue that up is down and vice versa just because he
thinks the numbers say so.

The Jehova's witness of lift.

Oh Anthony! A special friend for you.


Bertie

[Bertie the Bunyip[_19_]]

jon > wrote in news:1193334432.867133.306890
@t8g2000prg.googlegroups.com:

> http://www.efluids.com/efluids/gallery/gallery_pages/Morris_3.jsp

And what's that mysterios fuzz on the top of the wings, fjukkwit?



Bertie

[jon]

On 16 Okt, 20:41, Jim Logajan > wrote:
> Thomas > wrote:
> > You may want to check out my web pages
> >http://www.physicsmyths.org.uk/bernoulli.htmand
> >http://www.physicsmyths.org.uk/drag.htm for a closer examination of
> > the physics behind the aerodynamicliftand drag.
>
> You might want to actually _include_Bernoulli'stheorem somewhere in your
> pages. You talk aboutBernoulli'sequation,Bernoulli'sprinciple, andBernoulli'slaw. And yet none of them are actually presented. Are you
> saying they all the same or all different? Why not use the terminology used
> by the professionals and stick with "Bernoulli'stheorem"? How about
> including references to relevant texts on your pages? It's not like serious
> texts and lab experiments haven't been done on the subject for a zillion
> years. It helps to show you know what you're talking about by showing
> you've first read the professional literature on the subject and done your
> own relevant research.
>
> You might also want to redraw your figures so they include vertical labeled
> arrows. Then present the assumptions and math needed to show your work and
> why you think the vertical magnitudes sum to zero. Just saying they do, or
> they only yield a torque, isn't good enough. It is more useful to _show_ -
> not pontificate and hand-wave.
>
> P.S. Chapter section 40-3 in volume 2 of Feynman's Lectures on Physics is
> as good a place as any to start.


Nobelprizewinner Feynman made a good statement about the fluid
Bernoulli equation was valid for, "ideal fluid".

Feynman called the perfect fluid for "dry water" and it did not
exsist i a real world, only the mathematical world.

[jon]

On 17 Okt, 01:48, Le Chaud Lapin > wrote:
> On Oct 16, 3:31 pm, Thomas > wrote:
>
>
>
>
>
> > On 16 Oct, 19:41, Jim Logajan > wrote:
>
> > > Thomas > wrote:
> > > > You may want to check out my web pages
> > > >http://www.physicsmyths.org.uk/bernoulli.htmand
> > > >http://www.physicsmyths.org.uk/drag.htmfora closer examination of
> > > > the physics behind the aerodynamicliftand drag.
>
> > > You might want to actually _include_Bernoulli'stheorem somewhere in your
> > > pages. You talk aboutBernoulli'sequation,Bernoulli'sprinciple, and
> > >Bernoulli'slaw. And yet none of them are actually presented. Are you
> > > saying they all the same or all different? Why not use the terminology used
> > > by the professionals and stick with "Bernoulli'stheorem"? How about
> > > including references to relevant texts on your pages? It's not like serious
> > > texts and lab experiments haven't been done on the subject for a zillion
> > > years. It helps to show you know what you're talking about by showing
> > > you've first read the professional literature on the subject and done your
> > > own relevant research.
>
> > > You might also want to redraw your figures so they include vertical labeled
> > > arrows. Then present the assumptions and math needed to show your work and
> > > why you think the vertical magnitudes sum to zero. Just saying they do, or
> > > they only yield a torque, isn't good enough. It is more useful to _show_ -
> > > not pontificate and hand-wave.
>
> > > P.S. Chapter section 40-3 in volume 2 of Feynman's Lectures on Physics is
> > > as good a place as any to start.
>
> >Bernoulli'stheorem is not a fundamental physical law and thus not
> > required to understand the principle behind the aerodynamiclift. And
> > its misinterpretation and misapplication quite evidently leads to
> > incorrect physical conclusions, like the claim that a moving gas would
> > inherently have a lower static pressure than a stationary one. The net
> > flow velocity of a gas has per se nothing to do with the static
> > pressure.
>
> I so agree. The amout of hand-waving that goes on when (presumably
> technically-inclined) individuals invokeBernoulliis perplexing.
> Oddly, my college physics book is almost as guilty - after chapters
> and chapters of Newtonian mechanics that are quite clear, they seem to
> imply just that.
>
>
>
>
>
> > As a thought experiment, consider a large tank containing gas with a
> > pipe attached to it which leads into a vacuum space. Assume first this
> > pipe is closed at the end; then the flow velocity in the pipe is zero
> > because the molecules heading outwards will be reflected at the end
> > and reverse their velocity (assume for simplicity that the molecules
> > do not collide with each other but only with the walls of the pipe and
> > the tank). If one now opens the pipe, the only thing that changes is
> > that the molecules heading outwards will not be reflected anymore at
> > the end but simply carry on heading into the vacuum space (with the
> > corresponding loss of molecules being replaced from the large tank).
> > So we now have a net flow velocity within the pipe without that either
> > the density nor the speed of the molecules has changed in any way.
> > This means that the pressure exerted on the inside wall of the pipe is
> > unchanged despite the fact that we now have a net flow velocity within
> > it. SoBernoulli'stheorem would quite evidently give a wrong result
> > here.
>
> Hmmm...technically, someone could argue that, in the vicinity of the
> exit hole of the tank, there would be resulting decrease in pressure,
> which would be true.
>
> The misapplication, I think, results from too much hand-waving and not
> being very specific about what pressure decreases over what. A venturi
> apparutus, for example, very clearly demonstrates a drop in pressure,
> and that drop is real, but the points chosen to measure the pressure
> in the apparutus is very specific.
>
> -Le Chaud Lapin-- Dölj citerad text -
>
> - Visa citerad text -- Dölj citerad text -
>
> - Visa citerad text -

The venturi pipe is mostly misunderstood. To get through the narrow
section, the fluid must be pressed against the convergent part with a
higher pressure. The Coanda effect forces the fluid to follow the
walls in the divergent part.

All early speed sensors in 1920 used only the divergent part of the
venturi pipe.

Look att Bleriot and other planes. Look at Piper Colt 1953 model with
its backpart venturi. The front convergent part was not needed.

Changing the airflow direction over and under the wing, creates the
local pressure gradients + or - .

[Bertie the Bunyip[_19_]]

jon > wrote in
oups.com:

> On 16 Okt, 20:41, Jim Logajan > wrote:
>> Thomas > wrote:
>> > You may want to check out my web pages
>> >http://www.physicsmyths.org.uk/bernoulli.htmand
>> >http://www.physicsmyths.org.uk/drag.htm for a closer examination of
>> > the physics behind the aerodynamicliftand drag.
>>
>> You might want to actually _include_Bernoulli'stheorem somewhere in
>> your pages. You talk aboutBernoulli'sequation,Bernoulli'sprinciple,
>> andBernoulli'slaw. And yet none of them are actually presented. Are
>> you saying they all the same or all different? Why not use the
>> terminology used by the professionals and stick with
>> "Bernoulli'stheorem"? How about including references to relevant
>> texts on your pages? It's not like serious texts and lab experiments
>> haven't been done on the subject for a zillion years. It helps to
>> show you know what you're talking about by showing you've first read
>> the professional literature on the subject and done your own relevant
>> research.
>>
>> You might also want to redraw your figures so they include vertical
>> labeled arrows. Then present the assumptions and math needed to show
>> your work and why you think the vertical magnitudes sum to zero. Just
>> saying they do, or they only yield a torque, isn't good enough. It is
>> more useful to _show_ - not pontificate and hand-wave.
>>
>> P.S. Chapter section 40-3 in volume 2 of Feynman's Lectures on
>> Physics is as good a place as any to start.
>
>
> Nobelprizewinner Feynman made a good statement about the fluid
> Bernoulli equation was valid for, "ideal fluid".
>
> Feynman called the perfect fluid for "dry water" and it did not
> exsist i a real world, only the mathematical world.
>


You're an idiot.


Bertie

[Bertie the Bunyip[_19_]]

jon > wrote in
oups.com:

> On 17 Okt, 01:48, Le Chaud Lapin > wrote:
>> On Oct 16, 3:31 pm, Thomas > wrote:
>>
>>
>>
>>
>>
>> > On 16 Oct, 19:41, Jim Logajan > wrote:
>>
>> > > Thomas > wrote:
>> > > > You may want to check out my web pages
>> > > >http://www.physicsmyths.org.uk/bernoulli.htmand
>> > > >http://www.physicsmyths.org.uk/drag.htmfora closer examination
>> > > >of
>> > > > the physics behind the aerodynamicliftand drag.
>>
>> > > You might want to actually _include_Bernoulli'stheorem somewhere
>> > > in y
> our
>> > > pages. You talk aboutBernoulli'sequation,Bernoulli'sprinciple,
>> > > and
>> > >Bernoulli'slaw. And yet none of them are actually presented. Are
>> > >you
>> > > saying they all the same or all different? Why not use the
>> > > terminolog
> y used
>> > > by the professionals and stick with "Bernoulli'stheorem"? How
>> > > about including references to relevant texts on your pages? It's
>> > > not like s
> erious
>> > > texts and lab experiments haven't been done on the subject for a
>> > > zill
> ion
>> > > years. It helps to show you know what you're talking about by
>> > > showing you've first read the professional literature on the
>> > > subject and done
> your
>> > > own relevant research.
>>
>> > > You might also want to redraw your figures so they include
>> > > vertical l
> abeled
>> > > arrows. Then present the assumptions and math needed to show your
>> > > wor
> k and
>> > > why you think the vertical magnitudes sum to zero. Just saying
>> > > they d
> o, or
>> > > they only yield a torque, isn't good enough. It is more useful to
>> > > _sh
> ow_ -
>> > > not pontificate and hand-wave.
>>
>> > > P.S. Chapter section 40-3 in volume 2 of Feynman's Lectures on
>> > > Physic
> s is
>> > > as good a place as any to start.
>>
>> >Bernoulli'stheorem is not a fundamental physical law and thus not
>> > required to understand the principle behind the aerodynamiclift.
>> > And its misinterpretation and misapplication quite evidently leads
>> > to incorrect physical conclusions, like the claim that a moving gas
>> > would inherently have a lower static pressure than a stationary
>> > one. The net flow velocity of a gas has per se nothing to do with
>> > the static pressure.
>>
>> I so agree. The amout of hand-waving that goes on when (presumably
>> technically-inclined) individuals invokeBernoulliis perplexing.
>> Oddly, my college physics book is almost as guilty - after chapters
>> and chapters of Newtonian mechanics that are quite clear, they seem
>> to imply just that.
>>
>>
>>
>>
>>
>> > As a thought experiment, consider a large tank containing gas with
>> > a pipe attached to it which leads into a vacuum space. Assume first
>> > this pipe is closed at the end; then the flow velocity in the pipe
>> > is zero because the molecules heading outwards will be reflected at
>> > the end and reverse their velocity (assume for simplicity that the
>> > molecules do not collide with each other but only with the walls of
>> > the pipe and the tank). If one now opens the pipe, the only thing
>> > that changes is that the molecules heading outwards will not be
>> > reflected anymore at the end but simply carry on heading into the
>> > vacuum space (with the corresponding loss of molecules being
>> > replaced from the large tank). So we now have a net flow velocity
>> > within the pipe without that either the density nor the speed of
>> > the molecules has changed in any way. This means that the pressure
>> > exerted on the inside wall of the pipe is unchanged despite the
>> > fact that we now have a net flow velocity within it.
>> > SoBernoulli'stheorem would quite evidently give a wrong result
>> > here.
>>
>> Hmmm...technically, someone could argue that, in the vicinity of the
>> exit hole of the tank, there would be resulting decrease in pressure,
>> which would be true.
>>
>> The misapplication, I think, results from too much hand-waving and
>> not being very specific about what pressure decreases over what. A
>> venturi apparutus, for example, very clearly demonstrates a drop in
>> pressure, and that drop is real, but the points chosen to measure the
>> pressure in the apparutus is very specific.
>>
>> -Le Chaud Lapin-- Dölj citerad text -
>>
>> - Visa citerad text -- Dölj citerad text -
>>
>> - Visa citerad text -
>
> The venturi pipe is mostly misunderstood. To get through the narrow
> section, the fluid must be pressed against the convergent part with a
> higher pressure. The Coanda effect forces the fluid to follow the
> walls in the divergent part.
>
> All early speed sensors in 1920 used only the divergent part of the
> venturi pipe.
>
> Look att Bleriot and other planes. Look at Piper Colt 1953 model with
> its backpart venturi. The front convergent part was not needed.
>

Piper Colt 1953 model?


Unh unh. First flew in 1960 you fjukkwit.



Backpart Venturi?


Bwawhahwhahwhahwhahwhahwha!


> Changing the airflow direction over and under the wing, creates the
> local pressure gradients + or - .


Nope.


Bertie
>
>

[jon]

On 26 Okt, 08:24, Bertie the Bunyip > wrote:
> jon > wrote groups.com:
>
>
>
>
>
> > On 17 Okt, 01:48, Le Chaud Lapin > wrote:
> >> On Oct 16, 3:31 pm, Thomas > wrote:
>
> >> > On 16 Oct, 19:41, Jim Logajan > wrote:
>
> >> > > Thomas > wrote:
> >> > > > You may want to check out my web pages
> >> > > >http://www.physicsmyths.org.uk/bernoulli.htmand
> >> > > >http://www.physicsmyths.org.uk/drag.htmforacloser examination
> >> > > >of
> >> > > > the physics behind the aerodynamicliftand drag.
>
> >> > > You might want to actually _include_Bernoulli'stheorem somewhere
> >> > > in y
> > our
> >> > > pages. You talk aboutBernoulli'sequation,Bernoulli'sprinciple,
> >> > > and
> >> > >Bernoulli'slaw. And yet none of them are actually presented. Are
> >> > >you
> >> > > saying they all the same or all different? Why not use the
> >> > > terminolog
> > y used
> >> > > by the professionals and stick with "Bernoulli'stheorem"? How
> >> > > about including references to relevant texts on your pages? It's
> >> > > not like s
> > erious
> >> > > texts and lab experiments haven't been done on the subject for a
> >> > > zill
> > ion
> >> > > years. It helps to show you know what you're talking about by
> >> > > showing you've first read the professional literature on the
> >> > > subject and done
> > your
> >> > > own relevant research.
>
> >> > > You might also want to redraw your figures so they include
> >> > > vertical l
> > abeled
> >> > > arrows. Then present the assumptions and math needed to show your
> >> > > wor
> > k and
> >> > > why you think the vertical magnitudes sum to zero. Just saying
> >> > > they d
> > o, or
> >> > > they only yield a torque, isn't good enough. It is more useful to
> >> > > _sh
> > ow_ -
> >> > > not pontificate and hand-wave.
>
> >> > > P.S. Chapter section 40-3 in volume 2 of Feynman's Lectures on
> >> > > Physic
> > s is
> >> > > as good a place as any to start.
>
> >> >Bernoulli'stheorem is not a fundamental physical law and thus not
> >> > required to understand the principle behind the aerodynamiclift.
> >> > And its misinterpretation and misapplication quite evidently leads
> >> > to incorrect physical conclusions, like the claim that a moving gas
> >> > would inherently have a lower static pressure than a stationary
> >> > one. The net flow velocity of a gas has per se nothing to do with
> >> > the static pressure.
>
> >> I so agree. The amout of hand-waving that goes on when (presumably
> >> technically-inclined) individuals invokeBernoulliis perplexing.
> >> Oddly, my college physics book is almost as guilty - after chapters
> >> and chapters of Newtonian mechanics that are quite clear, they seem
> >> to imply just that.
>
> >> > As a thought experiment, consider a large tank containing gas with
> >> > a pipe attached to it which leads into a vacuum space. Assume first
> >> > this pipe is closed at the end; then the flow velocity in the pipe
> >> > is zero because the molecules heading outwards will be reflected at
> >> > the end and reverse their velocity (assume for simplicity that the
> >> > molecules do not collide with each other but only with the walls of
> >> > the pipe and the tank). If one now opens the pipe, the only thing
> >> > that changes is that the molecules heading outwards will not be
> >> > reflected anymore at the end but simply carry on heading into the
> >> > vacuum space (with the corresponding loss of molecules being
> >> > replaced from the large tank). So we now have a net flow velocity
> >> > within the pipe without that either the density nor the speed of
> >> > the molecules has changed in any way. This means that the pressure
> >> > exerted on the inside wall of the pipe is unchanged despite the
> >> > fact that we now have a net flow velocity within it.
> >> > SoBernoulli'stheorem would quite evidently give a wrong result
> >> > here.
>
> >> Hmmm...technically, someone could argue that, in the vicinity of the
> >> exit hole of the tank, there would be resulting decrease in pressure,
> >> which would be true.
>
> >> The misapplication, I think, results from too much hand-waving and
> >> not being very specific about what pressure decreases over what. A
> >> venturi apparutus, for example, very clearly demonstrates a drop in
> >> pressure, and that drop is real, but the points chosen to measure the
> >> pressure in the apparutus is very specific.
>
> >> -Le Chaud Lapin-- Dölj citerad text -
>
> >> - Visa citerad text -- Dölj citerad text -
>
> >> - Visa citerad text -
>
> > The venturi pipe is mostly misunderstood. To get through the narrow
> > section, the fluid must be pressed against the convergent part with a
> > higher pressure. The Coanda effect forces the fluid to follow the
> > walls in the divergent part.
>
> > All early speed sensors in 1920 used only the divergent part of the
> > venturi pipe.
>
> > Look att Bleriot and other planes. Look at Piper Colt 1953 model with
> > its backpart venturi. The front convergent part was not needed.
>
> Piper Colt 1953 model?
>
> Unh unh. First flew in 1960 you fjukkwit.
>
> Backpart Venturi?
>
> Bwawhahwhahwhahwhahwhahwha!
>
> > Changing the airflow direction over and under the wing, creates the
> > local pressure gradients + or - .
>
> Nope.
>
> Bertie
>
>
>
> - Dölj citerad text -
>
> - Visa citerad text -- Dölj citerad text -
>
> - Visa citerad text -


You must be very stupid Bertie, when don´t even know when Piper Colt
was introduced:

Piper PA-22 Tri-Pacer
The Pacer was originally designed as a tailwheel aircraft and thus had
somewhat limited forward visibility on the ground and more demanding
ground-handling characteristics. To help introduce more pilots to
easier, safer flying, in 1953 the PA-20 was redesigned and offered as
the PA-22 Tri-Pacer with a nosewheel in place of the tailwheel landing
gear. Additionally, the Tri-Pacer offered higher-powered engine
options in the form of 150 hp (112 kW) and 160 HP (120 kW) engines,
whereas the largest engine available to the original Pacer had an
output of 135 hp (100 kW).[1] At the time the tricycle undercarriage
became a popular preference and 1953 saw the PA-22 Tri-Pacer outsell
the Pacer by a ratio of six to one.

[Bertie the Bunyip[_19_]]

jon > wrote in
ups.com:

> On 26 Okt, 08:24, Bertie the Bunyip > wrote:
>> jon > wrote
>> innews:1193336318.130848.213230@i13g2000pr
> f.googlegroups.com:
>>
>>
>>
>>
>>
>> > On 17 Okt, 01:48, Le Chaud Lapin > wrote:
>> >> On Oct 16, 3:31 pm, Thomas > wrote:
>>
>> >> > On 16 Oct, 19:41, Jim Logajan > wrote:
>>
>> >> > > Thomas > wrote:
>> >> > > > You may want to check out my web pages
>> >> > > >http://www.physicsmyths.org.uk/bernoulli.htmand
>> >> > > >http://www.physicsmyths.org.uk/drag.htmforacloser examination
>> >> > > >of
>> >> > > > the physics behind the aerodynamicliftand drag.
>>
>> >> > > You might want to actually _include_Bernoulli'stheorem
>> >> > > somewhere in y
>> > our
>> >> > > pages. You talk aboutBernoulli'sequation,Bernoulli'sprinciple,
>> >> > > and
>> >> > >Bernoulli'slaw. And yet none of them are actually presented.
>> >> > >Are you
>> >> > > saying they all the same or all different? Why not use the
>> >> > > terminolog
>> > y used
>> >> > > by the professionals and stick with "Bernoulli'stheorem"? How
>> >> > > about including references to relevant texts on your pages?
>> >> > > It's not like s
>> > erious
>> >> > > texts and lab experiments haven't been done on the subject for
>> >> > > a zill
>> > ion
>> >> > > years. It helps to show you know what you're talking about by
>> >> > > showing you've first read the professional literature on the
>> >> > > subject and done
>> > your
>> >> > > own relevant research.
>>
>> >> > > You might also want to redraw your figures so they include
>> >> > > vertical l
>> > abeled
>> >> > > arrows. Then present the assumptions and math needed to show
>> >> > > your wor
>> > k and
>> >> > > why you think the vertical magnitudes sum to zero. Just saying
>> >> > > they d
>> > o, or
>> >> > > they only yield a torque, isn't good enough. It is more useful
>> >> > > to _sh
>> > ow_ -
>> >> > > not pontificate and hand-wave.
>>
>> >> > > P.S. Chapter section 40-3 in volume 2 of Feynman's Lectures on
>> >> > > Physic
>> > s is
>> >> > > as good a place as any to start.
>>
>> >> >Bernoulli'stheorem is not a fundamental physical law and thus not
>> >> > required to understand the principle behind the aerodynamiclift.
>> >> > And its misinterpretation and misapplication quite evidently
>> >> > leads to incorrect physical conclusions, like the claim that a
>> >> > moving gas would inherently have a lower static pressure than a
>> >> > stationary one. The net flow velocity of a gas has per se
>> >> > nothing to do with the static pressure.
>>
>> >> I so agree. The amout of hand-waving that goes on when
>> >> (presumably technically-inclined) individuals invokeBernoulliis
>> >> perplexing. Oddly, my college physics book is almost as guilty -
>> >> after chapters and chapters of Newtonian mechanics that are quite
>> >> clear, they seem to imply just that.
>>
>> >> > As a thought experiment, consider a large tank containing gas
>> >> > with a pipe attached to it which leads into a vacuum space.
>> >> > Assume first this pipe is closed at the end; then the flow
>> >> > velocity in the pipe is zero because the molecules heading
>> >> > outwards will be reflected at the end and reverse their velocity
>> >> > (assume for simplicity that the molecules do not collide with
>> >> > each other but only with the walls of the pipe and the tank). If
>> >> > one now opens the pipe, the only thing that changes is that the
>> >> > molecules heading outwards will not be reflected anymore at the
>> >> > end but simply carry on heading into the vacuum space (with the
>> >> > corresponding loss of molecules being replaced from the large
>> >> > tank). So we now have a net flow velocity within the pipe
>> >> > without that either the density nor the speed of the molecules
>> >> > has changed in any way. This means that the pressure exerted on
>> >> > the inside wall of the pipe is unchanged despite the fact that
>> >> > we now have a net flow velocity within it. SoBernoulli'stheorem
>> >> > would quite evidently give a wrong result here.
>>
>> >> Hmmm...technically, someone could argue that, in the vicinity of
>> >> the exit hole of the tank, there would be resulting decrease in
>> >> pressure, which would be true.
>>
>> >> The misapplication, I think, results from too much hand-waving and
>> >> not being very specific about what pressure decreases over what. A
>> >> venturi apparutus, for example, very clearly demonstrates a drop
>> >> in pressure, and that drop is real, but the points chosen to
>> >> measure the pressure in the apparutus is very specific.
>>
>> >> -Le Chaud Lapin-- Dölj citerad text -
>>
>> >> - Visa citerad text -- Dölj citerad text -
>>
>> >> - Visa citerad text -
>>
>> > The venturi pipe is mostly misunderstood. To get through the
>> > narrow section, the fluid must be pressed against the convergent
>> > part with a higher pressure. The Coanda effect forces the fluid to
>> > follow the walls in the divergent part.
>>
>> > All early speed sensors in 1920 used only the divergent part of the
>> > venturi pipe.
>>
>> > Look att Bleriot and other planes. Look at Piper Colt 1953 model
>> > with its backpart venturi. The front convergent part was not
>> > needed.
>>
>> Piper Colt 1953 model?
>>
>> Unh unh. First flew in 1960 you fjukkwit.
>>
>> Backpart Venturi?
>>
>> Bwawhahwhahwhahwhahwhahwha!
>>
>> > Changing the airflow direction over and under the wing, creates the
>> > local pressure gradients + or - .
>>
>> Nope.
>>
>> Bertie
>>
>>
>>
>> - Dölj citerad text -
>>
>> - Visa citerad text -- Dölj citerad text -
>>
>> - Visa citerad text -
>
>
> You must be very stupid Bertie, when don´t even know when Piper Colt
> was introduced:
>
> Piper PA-22 Tri-Pacer


Nope, that's a Tripacer, different airplane, fjukkwit.



> The Pacer was originally designed as a tailwheel aircraft and thus had
> somewhat limited forward visibility on the ground and more demanding
> ground-handling characteristics. To help introduce more pilots to
> easier, safer flying, in 1953 the PA-20 was redesigned and offered as
> the PA-22 Tri-Pacer with a nosewheel in place of the tailwheel landing
> gear. Additionally, the Tri-Pacer offered higher-powered engine
> options in the form of 150 hp (112 kW) and 160 HP (120 kW) engines,
> whereas the largest engine available to the original Pacer had an
> output of 135 hp (100 kW).[1] At the time the tricycle undercarriage
> became a popular preference and 1953 saw the PA-22 Tri-Pacer outsell
> the Pacer by a ratio of six to one.

btw, I';ve flown the pacer, Tr-pacer and colt Fjukkwit.

The colt has an O-235, not an O-290 or O-320, so you're tlaking out your
ass, just like when you talk aerodynamics.

Haven;'t heard you 'splain th efog on the top wing in that foto yet,
either fjukkwit.


Man you're dumb.


Bertie
>
>
P.S., do tell th eboys and gurls what you do for a living.


It's jus plain scary.

[jon]

On 26 Okt, 08:24, Bertie the Bunyip > wrote:
> jon > wrote groups.com:
>
>
>
>
>
> > On 17 Okt, 01:48, Le Chaud Lapin > wrote:
> >> On Oct 16, 3:31 pm, Thomas > wrote:
>
> >> > On 16 Oct, 19:41, Jim Logajan > wrote:
>
> >> > > Thomas > wrote:
> >> > > > You may want to check out my web pages
> >> > > >http://www.physicsmyths.org.uk/bernoulli.htmand
> >> > > >http://www.physicsmyths.org.uk/drag.htmforacloser examination
> >> > > >of
> >> > > > the physics behind the aerodynamicliftand drag.
>
> >> > > You might want to actually _include_Bernoulli'stheorem somewhere
> >> > > in y
> > our
> >> > > pages. You talk aboutBernoulli'sequation,Bernoulli'sprinciple,
> >> > > and
> >> > >Bernoulli'slaw. And yet none of them are actually presented. Are
> >> > >you
> >> > > saying they all the same or all different? Why not use the
> >> > > terminolog
> > y used
> >> > > by the professionals and stick with "Bernoulli'stheorem"? How
> >> > > about including references to relevant texts on your pages? It's
> >> > > not like s
> > erious
> >> > > texts and lab experiments haven't been done on the subject for a
> >> > > zill
> > ion
> >> > > years. It helps to show you know what you're talking about by
> >> > > showing you've first read the professional literature on the
> >> > > subject and done
> > your
> >> > > own relevant research.
>
> >> > > You might also want to redraw your figures so they include
> >> > > vertical l
> > abeled
> >> > > arrows. Then present the assumptions and math needed to show your
> >> > > wor
> > k and
> >> > > why you think the vertical magnitudes sum to zero. Just saying
> >> > > they d
> > o, or
> >> > > they only yield a torque, isn't good enough. It is more useful to
> >> > > _sh
> > ow_ -
> >> > > not pontificate and hand-wave.
>
> >> > > P.S. Chapter section 40-3 in volume 2 of Feynman's Lectures on
> >> > > Physic
> > s is
> >> > > as good a place as any to start.
>
> >> >Bernoulli'stheorem is not a fundamental physical law and thus not
> >> > required to understand the principle behind the aerodynamiclift.
> >> > And its misinterpretation and misapplication quite evidently leads
> >> > to incorrect physical conclusions, like the claim that a moving gas
> >> > would inherently have a lower static pressure than a stationary
> >> > one. The net flow velocity of a gas has per se nothing to do with
> >> > the static pressure.
>
> >> I so agree. The amout of hand-waving that goes on when (presumably
> >> technically-inclined) individuals invokeBernoulliis perplexing.
> >> Oddly, my college physics book is almost as guilty - after chapters
> >> and chapters of Newtonian mechanics that are quite clear, they seem
> >> to imply just that.
>
> >> > As a thought experiment, consider a large tank containing gas with
> >> > a pipe attached to it which leads into a vacuum space. Assume first
> >> > this pipe is closed at the end; then the flow velocity in the pipe
> >> > is zero because the molecules heading outwards will be reflected at
> >> > the end and reverse their velocity (assume for simplicity that the
> >> > molecules do not collide with each other but only with the walls of
> >> > the pipe and the tank). If one now opens the pipe, the only thing
> >> > that changes is that the molecules heading outwards will not be
> >> > reflected anymore at the end but simply carry on heading into the
> >> > vacuum space (with the corresponding loss of molecules being
> >> > replaced from the large tank). So we now have a net flow velocity
> >> > within the pipe without that either the density nor the speed of
> >> > the molecules has changed in any way. This means that the pressure
> >> > exerted on the inside wall of the pipe is unchanged despite the
> >> > fact that we now have a net flow velocity within it.
> >> > SoBernoulli'stheorem would quite evidently give a wrong result
> >> > here.
>
> >> Hmmm...technically, someone could argue that, in the vicinity of the
> >> exit hole of the tank, there would be resulting decrease in pressure,
> >> which would be true.
>
> >> The misapplication, I think, results from too much hand-waving and
> >> not being very specific about what pressure decreases over what. A
> >> venturi apparutus, for example, very clearly demonstrates a drop in
> >> pressure, and that drop is real, but the points chosen to measure the
> >> pressure in the apparutus is very specific.
>
> >> -Le Chaud Lapin-- Dölj citerad text -
>
> >> - Visa citerad text -- Dölj citerad text -
>
> >> - Visa citerad text -
>
> > The venturi pipe is mostly misunderstood. To get through the narrow
> > section, the fluid must be pressed against the convergent part with a
> > higher pressure. The Coanda effect forces the fluid to follow the
> > walls in the divergent part.
>
> > All early speed sensors in 1920 used only the divergent part of the
> > venturi pipe.
>
> > Look att Bleriot and other planes. Look at Piper Colt 1953 model with
> > its backpart venturi. The front convergent part was not needed.
>
> Piper Colt 1953 model?
>
> Unh unh. First flew in 1960 you fjukkwit.
>
> Backpart Venturi?
>
> Bwawhahwhahwhahwhahwhahwha!
>
> > Changing the airflow direction over and under the wing, creates the
> > local pressure gradients + or - .
>
> Nope.
>
> Bertie
>
>
>
> - Dölj citerad text -
>
> - Visa citerad text -- Dölj citerad text -
>
> - Visa citerad text -

The backpart of a venturi is sitting also on the Piper Colt 1960-64
models, like it does on the 1953 TriPacer of the same family.

One does not need the convergent entrance part, to measure the
airspeed.

[Bertie the Bunyip[_19_]]

jon > wrote in
oups.com:

> On 26 Okt, 08:24, Bertie the Bunyip > wrote:
>> jon > wrote
>> innews:1193336318.130848.213230@i13g2000pr
> f.googlegroups.com:
>>
>>
>>
>>
>>
>> > On 17 Okt, 01:48, Le Chaud Lapin > wrote:
>> >> On Oct 16, 3:31 pm, Thomas > wrote:
>>
>> >> > On 16 Oct, 19:41, Jim Logajan > wrote:
>>
>> >> > > Thomas > wrote:
>> >> > > > You may want to check out my web pages
>> >> > > >http://www.physicsmyths.org.uk/bernoulli.htmand
>> >> > > >http://www.physicsmyths.org.uk/drag.htmforacloser examination
>> >> > > >of
>> >> > > > the physics behind the aerodynamicliftand drag.
>>
>> >> > > You might want to actually _include_Bernoulli'stheorem
>> >> > > somewhere in y
>> > our
>> >> > > pages. You talk aboutBernoulli'sequation,Bernoulli'sprinciple,
>> >> > > and
>> >> > >Bernoulli'slaw. And yet none of them are actually presented.
>> >> > >Are you
>> >> > > saying they all the same or all different? Why not use the
>> >> > > terminolog
>> > y used
>> >> > > by the professionals and stick with "Bernoulli'stheorem"? How
>> >> > > about including references to relevant texts on your pages?
>> >> > > It's not like s
>> > erious
>> >> > > texts and lab experiments haven't been done on the subject for
>> >> > > a zill
>> > ion
>> >> > > years. It helps to show you know what you're talking about by
>> >> > > showing you've first read the professional literature on the
>> >> > > subject and done
>> > your
>> >> > > own relevant research.
>>
>> >> > > You might also want to redraw your figures so they include
>> >> > > vertical l
>> > abeled
>> >> > > arrows. Then present the assumptions and math needed to show
>> >> > > your wor
>> > k and
>> >> > > why you think the vertical magnitudes sum to zero. Just saying
>> >> > > they d
>> > o, or
>> >> > > they only yield a torque, isn't good enough. It is more useful
>> >> > > to _sh
>> > ow_ -
>> >> > > not pontificate and hand-wave.
>>
>> >> > > P.S. Chapter section 40-3 in volume 2 of Feynman's Lectures on
>> >> > > Physic
>> > s is
>> >> > > as good a place as any to start.
>>
>> >> >Bernoulli'stheorem is not a fundamental physical law and thus not
>> >> > required to understand the principle behind the aerodynamiclift.
>> >> > And its misinterpretation and misapplication quite evidently
>> >> > leads to incorrect physical conclusions, like the claim that a
>> >> > moving gas would inherently have a lower static pressure than a
>> >> > stationary one. The net flow velocity of a gas has per se
>> >> > nothing to do with the static pressure.
>>
>> >> I so agree. The amout of hand-waving that goes on when
>> >> (presumably technically-inclined) individuals invokeBernoulliis
>> >> perplexing. Oddly, my college physics book is almost as guilty -
>> >> after chapters and chapters of Newtonian mechanics that are quite
>> >> clear, they seem to imply just that.
>>
>> >> > As a thought experiment, consider a large tank containing gas
>> >> > with a pipe attached to it which leads into a vacuum space.
>> >> > Assume first this pipe is closed at the end; then the flow
>> >> > velocity in the pipe is zero because the molecules heading
>> >> > outwards will be reflected at the end and reverse their velocity
>> >> > (assume for simplicity that the molecules do not collide with
>> >> > each other but only with the walls of the pipe and the tank). If
>> >> > one now opens the pipe, the only thing that changes is that the
>> >> > molecules heading outwards will not be reflected anymore at the
>> >> > end but simply carry on heading into the vacuum space (with the
>> >> > corresponding loss of molecules being replaced from the large
>> >> > tank). So we now have a net flow velocity within the pipe
>> >> > without that either the density nor the speed of the molecules
>> >> > has changed in any way. This means that the pressure exerted on
>> >> > the inside wall of the pipe is unchanged despite the fact that
>> >> > we now have a net flow velocity within it. SoBernoulli'stheorem
>> >> > would quite evidently give a wrong result here.
>>
>> >> Hmmm...technically, someone could argue that, in the vicinity of
>> >> the exit hole of the tank, there would be resulting decrease in
>> >> pressure, which would be true.
>>
>> >> The misapplication, I think, results from too much hand-waving and
>> >> not being very specific about what pressure decreases over what. A
>> >> venturi apparutus, for example, very clearly demonstrates a drop
>> >> in pressure, and that drop is real, but the points chosen to
>> >> measure the pressure in the apparutus is very specific.
>>
>> >> -Le Chaud Lapin-- Dölj citerad text -
>>
>> >> - Visa citerad text -- Dölj citerad text -
>>
>> >> - Visa citerad text -
>>
>> > The venturi pipe is mostly misunderstood. To get through the
>> > narrow section, the fluid must be pressed against the convergent
>> > part with a higher pressure. The Coanda effect forces the fluid to
>> > follow the walls in the divergent part.
>>
>> > All early speed sensors in 1920 used only the divergent part of the
>> > venturi pipe.
>>
>> > Look att Bleriot and other planes. Look at Piper Colt 1953 model
>> > with its backpart venturi. The front convergent part was not
>> > needed.
>>
>> Piper Colt 1953 model?
>>
>> Unh unh. First flew in 1960 you fjukkwit.
>>
>> Backpart Venturi?
>>
>> Bwawhahwhahwhahwhahwhahwha!
>>
>> > Changing the airflow direction over and under the wing, creates the
>> > local pressure gradients + or - .
>>
>> Nope.
>>
>> Bertie
>>
>>
>>
>> - Dölj citerad text -
>>
>> - Visa citerad text -- Dölj citerad text -
>>
>> - Visa citerad text -
>
> The backpart of a venturi is sitting also on the Piper Colt 1960-64
> models, like it does on the 1953 TriPacer of the same family.
>


They didn't make the colt from 60-64, fjukkwit.

> One does not need the convergent entrance part, to measure the
> airspeed.


One doesn't need a venturi to measure airspeed either, fjukkktard.


OH, BTW, we met real life once. the other pilots in the room nearly
****ed their pants laughing about you in the bar afterwards.

Why don't you tell he bois and gurls here what you do for a living?

Bertie

[Bertie the Bunyip[_19_]]

jon > wrote in
oups.com:

> On 26 Okt, 08:24, Bertie the Bunyip > wrote:
>> jon > wrote
>> innews:1193336318.130848.213230@i13g2000pr
> f.googlegroups.com:
>>


> The backpart of a venturi is sitting also on the Piper Colt 1960-64
> models, like it does on the 1953 TriPacer of the same family.
>
> One does not need the convergent entrance part, to measure the
> airspeed.
>
>


Oh, almost forgot.

Bwawhahwhawhahwhahwhahwhahwhhahwhahwhahwhahhwhahwh ahwhahwhhahwhahwhahwhahwh
ha!


God I love usenet.
Bertie

[Dave[_5_]]

If you will be satisfied with empirical evidence, stick your hand out
the window of the car while going 50-60 MPH. Experiment with different
angles of attack. You will no doubt experience lift when your hand has
a positive angle of attack. Poor man's wind tunnel - but illustrates
that just about anything relatively flat will fly
given enough speed and a positive angle of attack.

David Johnson

[jon]

On 27 Okt, 17:10, Bertie the Bunyip > wrote:
> jon > wrote groups.com:
>
>
>
>
>
> > On 26 Okt, 08:24, Bertie the Bunyip > wrote:
> >> jon > wrote
> >> innews:1193336318.130848.213230@i13g2000pr
> > f.googlegroups.com:
>
> >> > On 17 Okt, 01:48, Le Chaud Lapin > wrote:
> >> >> On Oct 16, 3:31 pm, Thomas > wrote:
>
> >> >> > On 16 Oct, 19:41, Jim Logajan > wrote:
>
> >> >> > > Thomas > wrote:
> >> >> > > > You may want to check out my web pages
> >> >> > > >http://www.physicsmyths.org.uk/bernoulli.htmand
> >> >> > > >http://www.physicsmyths.org.uk/drag.htmforacloserexamination
> >> >> > > >of
> >> >> > > > the physics behind the aerodynamicliftand drag.
>
> >> >> > > You might want to actually _include_Bernoulli'stheorem
> >> >> > > somewhere in y
> >> > our
> >> >> > > pages. You talk aboutBernoulli'sequation,Bernoulli'sprinciple,
> >> >> > > and
> >> >> > >Bernoulli'slaw. And yet none of them are actually presented.
> >> >> > >Are you
> >> >> > > saying they all the same or all different? Why not use the
> >> >> > > terminolog
> >> > y used
> >> >> > > by the professionals and stick with "Bernoulli'stheorem"? How
> >> >> > > about including references to relevant texts on your pages?
> >> >> > > It's not like s
> >> > erious
> >> >> > > texts and lab experiments haven't been done on the subject for
> >> >> > > a zill
> >> > ion
> >> >> > > years. It helps to show you know what you're talking about by
> >> >> > > showing you've first read the professional literature on the
> >> >> > > subject and done
> >> > your
> >> >> > > own relevant research.
>
> >> >> > > You might also want to redraw your figures so they include
> >> >> > > vertical l
> >> > abeled
> >> >> > > arrows. Then present the assumptions and math needed to show
> >> >> > > your wor
> >> > k and
> >> >> > > why you think the vertical magnitudes sum to zero. Just saying
> >> >> > > they d
> >> > o, or
> >> >> > > they only yield a torque, isn't good enough. It is more useful
> >> >> > > to _sh
> >> > ow_ -
> >> >> > > not pontificate and hand-wave.
>
> >> >> > > P.S. Chapter section 40-3 in volume 2 of Feynman's Lectures on
> >> >> > > Physic
> >> > s is
> >> >> > > as good a place as any to start.
>
> >> >> >Bernoulli'stheorem is not a fundamental physical law and thus not
> >> >> > required to understand the principle behind the aerodynamiclift.
> >> >> > And its misinterpretation and misapplication quite evidently
> >> >> > leads to incorrect physical conclusions, like the claim that a
> >> >> > moving gas would inherently have a lower static pressure than a
> >> >> > stationary one. The net flow velocity of a gas has per se
> >> >> > nothing to do with the static pressure.
>
> >> >> I so agree. The amout of hand-waving that goes on when
> >> >> (presumably technically-inclined) individuals invokeBernoulliis
> >> >> perplexing. Oddly, my college physics book is almost as guilty -
> >> >> after chapters and chapters of Newtonian mechanics that are quite
> >> >> clear, they seem to imply just that.
>
> >> >> > As a thought experiment, consider a large tank containing gas
> >> >> > with a pipe attached to it which leads into a vacuum space.
> >> >> > Assume first this pipe is closed at the end; then the flow
> >> >> > velocity in the pipe is zero because the molecules heading
> >> >> > outwards will be reflected at the end and reverse their velocity
> >> >> > (assume for simplicity that the molecules do not collide with
> >> >> > each other but only with the walls of the pipe and the tank). If
> >> >> > one now opens the pipe, the only thing that changes is that the
> >> >> > molecules heading outwards will not be reflected anymore at the
> >> >> > end but simply carry on heading into the vacuum space (with the
> >> >> > corresponding loss of molecules being replaced from the large
> >> >> > tank). So we now have a net flow velocity within the pipe
> >> >> > without that either the density nor the speed of the molecules
> >> >> > has changed in any way. This means that the pressure exerted on
> >> >> > the inside wall of the pipe is unchanged despite the fact that
> >> >> > we now have a net flow velocity within it. SoBernoulli'stheorem
> >> >> > would quite evidently give a wrong result here.
>
> >> >> Hmmm...technically, someone could argue that, in the vicinity of
> >> >> the exit hole of the tank, there would be resulting decrease in
> >> >> pressure, which would be true.
>
> >> >> The misapplication, I think, results from too much hand-waving and
> >> >> not being very specific about what pressure decreases over what. A
> >> >> venturi apparutus, for example, very clearly demonstrates a drop
> >> >> in pressure, and that drop is real, but the points chosen to
> >> >> measure the pressure in the apparutus is very specific.
>
> >> >> -Le Chaud Lapin-- Dölj citerad text -
>
> >> >> - Visa citerad text -- Dölj citerad text -
>
> >> >> - Visa citerad text -
>
> >> > The venturi pipe is mostly misunderstood. To get through the
> >> > narrow section, the fluid must be pressed against the convergent
> >> > part with a higher pressure. The Coanda effect forces the fluid to
> >> > follow the walls in the divergent part.
>
> >> > All early speed sensors in 1920 used only the divergent part of the
> >> > venturi pipe.
>
> >> > Look att Bleriot and other planes. Look at Piper Colt 1953 model
> >> > with its backpart venturi. The front convergent part was not
> >> > needed.
>
> >> Piper Colt 1953 model?
>
> >> Unh unh. First flew in 1960 you fjukkwit.
>
> >> Backpart Venturi?
>
> >> Bwawhahwhahwhahwhahwhahwha!
>
> >> > Changing the airflow direction over and under the wing, creates the
> >> > local pressure gradients + or - .
>
> >> Nope.
>
> >> Bertie
>
> >> - Dölj citerad text -
>
> >> - Visa citerad text -- Dölj citerad text -
>
> >> - Visa citerad text -
>
> > The backpart of a venturi is sitting also on the Piper Colt 1960-64
> > models, like it does on the 1953 TriPacer of the same family.
>
> They didn't make the colt from 60-64, fjukkwit.
>
> > One does not need the convergent entrance part, to measure the
> > airspeed.
>
> One doesn't need a venturi to measure airspeed either, fjukkktard.
>
> OH, BTW, we met real life once. the other pilots in the room nearly
> ****ed their pants laughing about you in the bar afterwards.
>
> Why don't you tell he bois and gurls here what you do for a living?
>
> Bertie- Dölj citerad text -
>
> - Visa citerad text -

Since you are such a superexpert Bertie, Bombardier needs your help to
fix the landinggear problem!

Now 9 incidents happened with failed landinggear!

We can not block more runways with Q400 anymore and we need your help
Bertie, since you know everything in the

aviation world.


And you still believe the aircrafts are sucked up in the sky, like
Apollo went to the moon?

[jon]

On 28 Okt, 05:39, Dave > wrote:
> If you will be satisfied with empirical evidence, stick your hand out
> the window of the car while going 50-60 MPH. Experiment with different
> angles of attack. You will no doubt experienceliftwhen your hand has
> a positive angle of attack. Poor man's wind tunnel - but illustrates
> that just about anything relatively flat will fly
> given enough speed and a positive angle of attack.
>
> David Johnson

The problem is probably, that Bertie does have a car, so the simple
experiment is not possible for him.

He might find a bus, where he can open the window and try.

The risk is that he does not understand the physical effects on his
hand.

Since he does not understand how to see the vertical airflow from the
wings at AOA in this picture, he has a big problem:

http://www.efluids.com/efluids/gallery/gallery_pages/Morris_4.jsp

[Bertie the Bunyip[_19_]]

jon > wrote in news:1193570966.513645.238920
@o38g2000hse.googlegroups.com:

> On 28 Okt, 05:39, Dave > wrote:
>> If you will be satisfied with empirical evidence, stick your hand out
>> the window of the car while going 50-60 MPH. Experiment with
different
>> angles of attack. You will no doubt experienceliftwhen your hand has
>> a positive angle of attack. Poor man's wind tunnel - but illustrates
>> that just about anything relatively flat will fly
>> given enough speed and a positive angle of attack.
>>
>> David Johnson
>
> The problem is probably, that Bertie does have a car, so the simple
> experiment is not possible for him.
>

Yep, I do have a car. an airplane too.

> He might find a bus, where he can open the window and try.
>
> The risk is that he does not understand the physical effects on his
> hand.
>
> Since he does not understand how to see the vertical airflow from the
> wings at AOA in this picture, he has a big problem:
>
> http://www.efluids.com/efluids/gallery/gallery_pages/Morris_3.jsp
>
Look again, fjukkwit.



You have yet to explain th elow on top of the wing..



Bertie
>
>
>

[Bertie the Bunyip[_19_]]

jon > wrote in
ups.com:

> On 27 Okt, 17:10, Bertie the Bunyip > wrote:
>> jon > wrote
>> innews:1193496270.442636.260090@d55g2000hs
> g.googlegroups.com:
>>
>>
>>
>>
>>
>> > On 26 Okt, 08:24, Bertie the Bunyip > wrote:
>> >> jon > wrote
>> >> innews:1193336318.130848.213230@i13g2000pr
>> > f.googlegroups.com:
>>
>> >> > On 17 Okt, 01:48, Le Chaud Lapin > wrote:
>> >> >> On Oct 16, 3:31 pm, Thomas > wrote:
>>
>> >> >> > On 16 Oct, 19:41, Jim Logajan > wrote:
>>
>> >> >> > > Thomas > wrote:
>> >> >> > > > You may want to check out my web pages
>> >> >> > > >http://www.physicsmyths.org.uk/bernoulli.htmand
>> >> >> > > >
http://www.physicsmyths.org.uk/drag.htmforacloserexaminatio
>> >> >> > > >n of
>> >> >> > > > the physics behind the aerodynamicliftand drag.
>>
>> >> >> > > You might want to actually _include_Bernoulli'stheorem
>> >> >> > > somewhere in y
>> >> > our
>> >> >> > > pages. You talk
>> >> >> > > aboutBernoulli'sequation,Bernoulli'sprinciple,
>> >> >> > > and
>> >> >> > >Bernoulli'slaw. And yet none of them are actually presented.
>> >> >> > >Are you
>> >> >> > > saying they all the same or all different? Why not use the
>> >> >> > > terminolog
>> >> > y used
>> >> >> > > by the professionals and stick with "Bernoulli'stheorem"?
>> >> >> > > How about including references to relevant texts on your
>> >> >> > > pages? It's not like s
>> >> > erious
>> >> >> > > texts and lab experiments haven't been done on the subject
>> >> >> > > for a zill
>> >> > ion
>> >> >> > > years. It helps to show you know what you're talking about
>> >> >> > > by showing you've first read the professional literature on
>> >> >> > > the subject and done
>> >> > your
>> >> >> > > own relevant research.
>>
>> >> >> > > You might also want to redraw your figures so they include
>> >> >> > > vertical l
>> >> > abeled
>> >> >> > > arrows. Then present the assumptions and math needed to
>> >> >> > > show your wor
>> >> > k and
>> >> >> > > why you think the vertical magnitudes sum to zero. Just
>> >> >> > > saying they d
>> >> > o, or
>> >> >> > > they only yield a torque, isn't good enough. It is more
>> >> >> > > useful to _sh
>> >> > ow_ -
>> >> >> > > not pontificate and hand-wave.
>>
>> >> >> > > P.S. Chapter section 40-3 in volume 2 of Feynman's Lectures
>> >> >> > > on Physic
>> >> > s is
>> >> >> > > as good a place as any to start.
>>
>> >> >> >Bernoulli'stheorem is not a fundamental physical law and thus
>> >> >> >not
>> >> >> > required to understand the principle behind the
>> >> >> > aerodynamiclift. And its misinterpretation and misapplication
>> >> >> > quite evidently leads to incorrect physical conclusions, like
>> >> >> > the claim that a moving gas would inherently have a lower
>> >> >> > static pressure than a stationary one. The net flow velocity
>> >> >> > of a gas has per se nothing to do with the static pressure.
>>
>> >> >> I so agree. The amout of hand-waving that goes on when
>> >> >> (presumably technically-inclined) individuals invokeBernoulliis
>> >> >> perplexing. Oddly, my college physics book is almost as guilty
>> >> >> - after chapters and chapters of Newtonian mechanics that are
>> >> >> quite clear, they seem to imply just that.
>>
>> >> >> > As a thought experiment, consider a large tank containing gas
>> >> >> > with a pipe attached to it which leads into a vacuum space.
>> >> >> > Assume first this pipe is closed at the end; then the flow
>> >> >> > velocity in the pipe is zero because the molecules heading
>> >> >> > outwards will be reflected at the end and reverse their
>> >> >> > velocity (assume for simplicity that the molecules do not
>> >> >> > collide with each other but only with the walls of the pipe
>> >> >> > and the tank). If one now opens the pipe, the only thing that
>> >> >> > changes is that the molecules heading outwards will not be
>> >> >> > reflected anymore at the end but simply carry on heading into
>> >> >> > the vacuum space (with the corresponding loss of molecules
>> >> >> > being replaced from the large tank). So we now have a net
>> >> >> > flow velocity within the pipe without that either the density
>> >> >> > nor the speed of the molecules has changed in any way. This
>> >> >> > means that the pressure exerted on the inside wall of the
>> >> >> > pipe is unchanged despite the fact that we now have a net
>> >> >> > flow velocity within it. SoBernoulli'stheorem would quite
>> >> >> > evidently give a wrong result here.
>>
>> >> >> Hmmm...technically, someone could argue that, in the vicinity
>> >> >> of the exit hole of the tank, there would be resulting decrease
>> >> >> in pressure, which would be true.
>>
>> >> >> The misapplication, I think, results from too much hand-waving
>> >> >> and not being very specific about what pressure decreases over
>> >> >> what. A venturi apparutus, for example, very clearly
>> >> >> demonstrates a drop in pressure, and that drop is real, but the
>> >> >> points chosen to measure the pressure in the apparutus is very
>> >> >> specific.
>>
>> >> >> -Le Chaud Lapin-- Dölj citerad text -
>>
>> >> >> - Visa citerad text -- Dölj citerad text -
>>
>> >> >> - Visa citerad text -
>>
>> >> > The venturi pipe is mostly misunderstood. To get through the
>> >> > narrow section, the fluid must be pressed against the convergent
>> >> > part with a higher pressure. The Coanda effect forces the fluid
>> >> > to follow the walls in the divergent part.
>>
>> >> > All early speed sensors in 1920 used only the divergent part of
>> >> > the venturi pipe.
>>
>> >> > Look att Bleriot and other planes. Look at Piper Colt 1953 model
>> >> > with its backpart venturi. The front convergent part was not
>> >> > needed.
>>
>> >> Piper Colt 1953 model?
>>
>> >> Unh unh. First flew in 1960 you fjukkwit.
>>
>> >> Backpart Venturi?
>>
>> >> Bwawhahwhahwhahwhahwhahwha!
>>
>> >> > Changing the airflow direction over and under the wing, creates
>> >> > the local pressure gradients + or - .
>>
>> >> Nope.
>>
>> >> Bertie
>>
>> >> - Dölj citerad text -
>>
>> >> - Visa citerad text -- Dölj citerad text -
>>
>> >> - Visa citerad text -
>>
>> > The backpart of a venturi is sitting also on the Piper Colt 1960-64
>> > models, like it does on the 1953 TriPacer of the same family.
>>
>> They didn't make the colt from 60-64, fjukkwit.
>>
>> > One does not need the convergent entrance part, to measure the
>> > airspeed.
>>
>> One doesn't need a venturi to measure airspeed either, fjukkktard.
>>
>> OH, BTW, we met real life once. the other pilots in the room nearly
>> ****ed their pants laughing about you in the bar afterwards.
>>
>> Why don't you tell he bois and gurls here what you do for a living?
>>
>> Bertie- Dölj citerad text -
>>
>> - Visa citerad text -
>
> Since you are such a superexpert Bertie, Bombardier needs your help to
> fix the landinggear problem!
>
> Now 9 incidents happened with failed landinggear!

So?

>
> We can not block more runways with Q400 anymore and we need your help
> Bertie, since you know everything in the
>
> aviation world.


Well, they need to make the gear stronger and more reliable.


happy?

>
>
> And you still believe the aircrafts are sucked up in the sky, like
> Apollo went to the moon?




God I love usenet.


Bertie>

[Gatt]

"Dave" > wrote in message
ups.com...
> If you will be satisfied with empirical evidence, stick your hand out
> the window of the car while going 50-60 MPH. Experiment with different
> angles of attack. You will no doubt experience lift when your hand has
> a positive angle of attack. Poor man's wind tunnel - but illustrates
> that just about anything relatively flat will fly
> given enough speed and a positive angle of attack.

That's why wings have camber. 'Cause they don't need 'em.

Bertie's a shill for the Alcoa Camber Conspiracy. ...they've sold more
metal by convincing every successful aircraft designer and manufacturer in
the history of aviation that upper camber is necessary, when all they need
are two simple deflection plates.

Fortunately, the wizards at sci.physics have busted the conspiracy and we
all see now how the designers of all aircraft were grievously wrong.

-c

[Bertie the Bunyip[_19_]]

"Gatt" > wrote in
:

>
> "Dave" > wrote in message
> ups.com...
>> If you will be satisfied with empirical evidence, stick your hand out
>> the window of the car while going 50-60 MPH. Experiment with
>> different angles of attack. You will no doubt experience lift when
>> your hand has a positive angle of attack. Poor man's wind tunnel -
>> but illustrates that just about anything relatively flat will fly
>> given enough speed and a positive angle of attack.
>
> That's why wings have camber. 'Cause they don't need 'em.
>
> Bertie's a shill for the Alcoa Camber Conspiracy. ...they've sold
> more metal by convincing every successful aircraft designer and
> manufacturer in the history of aviation that upper camber is
> necessary, when all they need are two simple deflection plates.


Yeah, that's it. Also, I get good money from the guys who deice aircraft
upper surfaces..
>
> Fortunately, the wizards at sci.physics have busted the conspiracy and
> we all see now how the designers of all aircraft were grievously
> wrong.


It had to end for me sometime. ;(

Well, I had a good run..



Bertie