Question to Mxmanic

[Snowbird]

How does MS flight simulator simulate the symptoms of hypoxia?

[Morgans[_2_]]

"Snowbird" > wrote in message
.fi...
> How does MS flight simulator simulate the symptoms of hypoxia?

Mercy, don't stimulate conversation with the troll, ... please???

[Mxsmanic]

Snowbird writes:

> How does MS flight simulator simulate the symptoms of hypoxia?

No provision is made for simulation of hypoxia of altitude. If the aircraft
is accelerated, the simulator does simulate the visual effects of positive and
negative Gs.

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[Snowbird]

"Mxsmanic" wrote ...
>
> No provision is made for simulation of hypoxia of altitude.
>

So MS flight simulator is not realistic then. That's what I wanted to know.

[Mxsmanic]

Snowbird writes:

> So MS flight simulator is not realistic then.

That depends on what aspect of flight you wish to simulate. Even full-motion
simulators certified by the FAA do not simulate hypoxia, unless they are
high-altitude chambers (but those don't simulate anything else).

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[buttman]

On Apr 12, 10:51 pm, "Snowbird" > wrote:
> How does MS flight simulator simulate the symptoms of hypoxia?

HUUUUURRRRRR

[Viperdoc[_4_]]

So, now MX is an aerospace physiologist? What was it like riding in the high
altitude chamber? What did you think of the rapid decompression?

And, how did it feel when MSFS simulated pulling or pushing G's? Did your
head get heavy? Did you grey or red out? Or perhaps you've ridden in a
centrifuge to nine G and experienced this as well.

Of course, you've heard or read about these experiences, so this makes you
an expert. On the other hand, I (and many others) have had the opportunity
to actually do these things.

You can read or play with your computer all you want- it may give you
knowledge but it will never give you experience. At the end of all your
diatribe you still will have zero flight hours logged, and even zero sim
time logged. In other words- no flying experience at all.

[karl gruber[_1_]]

Half a bottle of Jack Daniel's


"Curator"



"Snowbird" > wrote in message
.fi...
> How does MS flight simulator simulate the symptoms of hypoxia?
>

[Matt Barrow[_4_]]

"karl gruber" > wrote in message
...
> Half a bottle of Jack Daniel's
>


Wimp!!

>
> "Curator"
>
>
>
> "Snowbird" > wrote in message
> .fi...
>> How does MS flight simulator simulate the symptoms of hypoxia?
>>
>
>

[Little Endian]

>
> No provision is made for simulation of hypoxia of altitude. If the aircraft
> is accelerated, the simulator does simulate the visual effects of positive and
> negative Gs.

Does MSFS simulate wake turbulence? From the little that I have seen
it does not seem to. Are there other regular PC based simulators that
do?

[Mxsmanic]

Viperdoc writes:

> And, how did it feel when MSFS simulated pulling or pushing G's? Did your
> head get heavy? Did you grey or red out? Or perhaps you've ridden in a
> centrifuge to nine G and experienced this as well.

MSFS simulates the gray out and red out. Obviously, there is no motion.

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[Mxsmanic]

Little Endian writes:

> Does MSFS simulate wake turbulence? From the little that I have seen
> it does not seem to. Are there other regular PC based simulators that
> do?

FS 2004 does not, nor does the built-in AI ATC delay for wake turbulence. I
don't know about FSX or other sim software.

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[Little Endian]

>
> FS 2004 does not, nor does the built-in AI ATC delay for wake turbulence. I
> don't know about FSX or other sim software.
>

Ok. So its much less realistic than I thought because wake turbulence
avoidance is a very important concern for real pilots.

[Mxsmanic]

Little Endian writes:

> Ok. So its much less realistic than I thought because wake turbulence
> avoidance is a very important concern for real pilots.

True, but it's not something that requires practice. In real life, you simply
take care to avoid wake turbulence; in the sim, you can take the same
precautions if you wish, but you don't have to.

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[Snowbird]

"Mxsmanic" wrote ...
> Little Endian writes:
>
>> Ok. So its much less realistic than I thought because wake turbulence
>> avoidance is a very important concern for real pilots.
>
> True, but it's not something that requires practice. In real life, you
> simply
> take care to avoid wake turbulence; in the sim, you can take the same
> precautions if you wish, but you don't have to.
>

Well, in real aviation the most valuable use of simulators is for practising
upsets and other abnormal situations that are not safe or feasible to do in
the real aircraft. So it would be an extremely useful feature to have in
MSFS.

In addition, if the feature were in MSFS, it would aid realism to basic
flight training as well i.e. flying a correct 360-degree turn.

[A Guy Called Tyketto]

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In rec.aviation.piloting Mxsmanic > wrote:
> Little Endian writes:
>
>> Ok. So its much less realistic than I thought because wake turbulence
>> avoidance is a very important concern for real pilots.
>
> True, but it's not something that requires practice. In real life, you simply
> take care to avoid wake turbulence; in the sim, you can take the same
> precautions if you wish, but you don't have to.
>

Am I the only one seeing the irony in this/

Someone who claims that a sim is close to real life, and wants
to do everything that is done in the real world, but thinks that it is
*OPTIONAL* to handle a problem that has killed people over the years?

You don't get to cherrypick operations like this. If you're in
a PC-12 and you come in 1 mile in trail of a B767, you don't get to
pick and say "I'm not going to take precautions for wake turbulence" in
the real world; you either do it, or you risk your life. If you want to
do this in the real world (which in your case, you don't (thank the
gods) ), you had best do what you can to avoid it, whether it's there
or not.

You contradict yourself with every statement you make, Anthony.

BL.
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Brad Littlejohn | Email:
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[Jay Honeck]

> > How does MS flight simulator simulate the symptoms of hypoxia?- Hide quoted text -

> Half a bottle of Jack Daniel's

It's funny you should say that. I have flown our MSFS-based "Kiwi"
flight simulator
(see it here: http://www.alexisparkinn.com/flight_simulator.htm ) at
the end of a very long day, after consuming three 16-ounce Sprecher
Ambers (within the span of a 114-minute movie), and can vouch for the
fact that alcohol is a pretty good mild hypoxia simulator.

;-)
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

[Steve Foley]

"karl gruber" > wrote in message
...
> Half a bottle of Jack Daniel's
>

Half full or half empty?

[ManhattanMan]

Steve Foley wrote:
> "karl gruber" > wrote in message
> ...
>> Half a bottle of Jack Daniel's
>>
>
> Half full or half empty?

from an engineering standpoint, the bottle wasn't designed
correctly........... :)

[Little Endian]

>
> True, but it's not something that requires practice. In real life, you simply
> take care to avoid wake turbulence; in the sim, you can take the same
> precautions if you wish, but you don't have to.

In the sim it makes no sense to avoid wake turbulence because you will
never know if you succeeded, its an exercise in futility.

[Mxsmanic]

Snowbird writes:

> Well, in real aviation the most valuable use of simulators is for practising
> upsets and other abnormal situations that are not safe or feasible to do in
> the real aircraft.

Not everyone uses simulation as practice for real aviation. There are many
possible purposes to which simulation can be put, and just as many different
types of simulators. No simulator simulates every aspect of reality
accurately, but nobody requires a duplicate of reality, only a reproduction of
those aspects of reality that are of interest.

> So it would be an extremely useful feature to have in MSFS.

I don't know that it would be "extremely" useful, but it would certainly be a
plus. Then again, if real pilots don't use MSFS for training, would it really
be that important?

Besides, the idea is to avoid wake turbulence, not to fly through it, so the
only real training required is procedural.

> In addition, if the feature were in MSFS, it would aid realism to basic
> flight training as well i.e. flying a correct 360-degree turn.

Are 360-degree turns common? Why would they encounter wake turbulence?

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[Mxsmanic]

Little Endian writes:

> In the sim it makes no sense to avoid wake turbulence because you will
> never know if you succeeded, its an exercise in futility.

Real life is like that, too. You only know when you fail to avoid wake
turbulence, not when you succeed.

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[Dudley Henriques[_2_]]

"ManhattanMan" > wrote in message
...
> Steve Foley wrote:
>> "karl gruber" > wrote in message
>> ...
>>> Half a bottle of Jack Daniel's
>>>
>>
>> Half full or half empty?
>
> from an engineering standpoint, the bottle wasn't designed
> correctly........... :)

I was JUST about to say this!!! :-))
Dudley Henriques

[Gary[_2_]]

On Apr 13, 7:23 pm, Mxsmanic > wrote:
> Little Endian writes:
> > In the sim it makes no sense to avoid wake turbulence because you will
> > never know if you succeeded, its an exercise in futility.
>
> Real life is like that, too. You only know when you fail to avoid wake
> turbulence, not when you succeed.
>


Couldn't be more wrong. In real life, you most certainly know when
you succeed in avoiding wake turbulence.

[george]

On Apr 14, 2:36 am, "Matt Barrow" >
wrote:
> "karl gruber" > wrote in message
>
> ...
>
> > Half a bottle of Jack Daniel's
>
> Wimp!!
>
He meant the bottom half.
After he'd drank the top half to get to it :-)

[Little Endian]

>
> Real life is like that, too. You only know when you fail to avoid wake
> turbulence, not when you succeed.

Incorrect statement.

[Mxsmanic]

Gary writes:

> Couldn't be more wrong. In real life, you most certainly know when
> you succeed in avoiding wake turbulence.

No, you don't. You don't know if you avoided it, or if it simply wasn't there
to begin with.

In any case, avoidance is the only safe procedure. Trying to fly in wake
turbulence isn't a good idea.

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[Mxsmanic]

Little Endian writes:

> Incorrect statement.

I'm always surprised by posts that simply say "wrong," but don't explain why.

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[ManhattanMan]

Dudley Henriques wrote:
> "ManhattanMan" > wrote in message
> ...
>> Steve Foley wrote:
>>> "karl gruber" > wrote in message
>>> ...
>>>> Half a bottle of Jack Daniel's
>>>>
>>>
>>> Half full or half empty?
>>
>> from an engineering standpoint, the bottle wasn't designed
>> correctly........... :)
>
> I was JUST about to say this!!! :-))
> Dudley Henriques

GOTCHA!! d:->))

[Dudley Henriques[_2_]]

"ManhattanMan" > wrote in message
...
> Dudley Henriques wrote:
>> "ManhattanMan" > wrote in message
>> ...
>>> Steve Foley wrote:
>>>> "karl gruber" > wrote in message
>>>> ...
>>>>> Half a bottle of Jack Daniel's
>>>>>
>>>>
>>>> Half full or half empty?
>>>
>>> from an engineering standpoint, the bottle wasn't designed
>>> correctly........... :)
>>
>> I was JUST about to say this!!! :-))
>> Dudley Henriques
>
> GOTCHA!! d:->))

The way this one got twisted around down at the Naval Test Pilot School was
as follows;

Procurement Office ; "This bottle is half empty"
Maintainence Office ; " This bottle is half full"
Flight Test Engineering Office :
"Yo Jack....call those idiots over at Procurement and tell them this damn
bottle is twice as big as it has to be "
Dudley Henriques

[Steve Foley[_2_]]

"Dudley Henriques" > wrote in message
...
>
> "ManhattanMan" > wrote in message
> ...
>> Dudley Henriques wrote:
>>> "ManhattanMan" > wrote in message
>>> ...
>>>> Steve Foley wrote:
>>>>> "karl gruber" > wrote in message
>>>>> ...
>>>>>> Half a bottle of Jack Daniel's
>>>>>>
>>>>>
>>>>> Half full or half empty?
>>>>
>>>> from an engineering standpoint, the bottle wasn't designed
>>>> correctly........... :)
>>>
>>> I was JUST about to say this!!! :-))
>>> Dudley Henriques
>>
>> GOTCHA!! d:->))
>
> The way this one got twisted around down at the Naval Test Pilot School
> was as follows;
>
> Procurement Office ; "This bottle is half empty"
> Maintainence Office ; " This bottle is half full"
> Flight Test Engineering Office :
> "Yo Jack....call those idiots over at Procurement and tell them this damn
> bottle is twice as big as it has to be "
> Dudley Henriques

Maintenance Shack: It's empty now.

[Dudley Henriques[_2_]]

"Steve Foley" > wrote in message
...
> "Dudley Henriques" > wrote in message
> ...
>>
>> "ManhattanMan" > wrote in message
>> ...
>>> Dudley Henriques wrote:
>>>> "ManhattanMan" > wrote in message
>>>> ...
>>>>> Steve Foley wrote:
>>>>>> "karl gruber" > wrote in message
>>>>>> ...
>>>>>>> Half a bottle of Jack Daniel's
>>>>>>>
>>>>>>
>>>>>> Half full or half empty?
>>>>>
>>>>> from an engineering standpoint, the bottle wasn't designed
>>>>> correctly........... :)
>>>>
>>>> I was JUST about to say this!!! :-))
>>>> Dudley Henriques
>>>
>>> GOTCHA!! d:->))
>>
>> The way this one got twisted around down at the Naval Test Pilot School
>> was as follows;
>>
>> Procurement Office ; "This bottle is half empty"
>> Maintainence Office ; " This bottle is half full"
>> Flight Test Engineering Office :
>> "Yo Jack....call those idiots over at Procurement and tell them this damn
>> bottle is twice as big as it has to be "
>> Dudley Henriques
>
> Maintenance Shack: It's empty now.

More likely....."those damn pilots will drink anything!!!"
:-))
Dudley Henriques

[A Guy Called Tyketto]

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In rec.aviation.piloting Mxsmanic > wrote:
> Gary writes:
>
>> Couldn't be more wrong. In real life, you most certainly know when
>> you succeed in avoiding wake turbulence.
>
> No, you don't. You don't know if you avoided it, or if it simply wasn't there
> to begin with.
>
> In any case, avoidance is the only safe procedure. Trying to fly in wake
> turbulence isn't a good idea.

And yet once again, you're a contradictory in terms. You say
you strive for realism in your sim and say something like the above,
but a few posts ago, you state:

"In real life, you simply take care to avoid wake turbulence;
in the sim, you can take the same precautions if you wish, but you don't
have to.

So basically, you can't even make up your mind on what you want
to do period.

You need help, Anthony. REAL WORLD help.

BL.
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Brad Littlejohn | Email:
Unix Systems Administrator, |
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[mike regish]

A sign of a well executed 360 is to encounter your own wake turbulence,
although the vortex generally sinks some in the intervening time and the
turbulence is usually no more than a slight bump.

Still, it's a gratifying feeling.

mike

"Mxsmanic" > wrote in message
...
>
> Are 360-degree turns common? Why would they encounter wake turbulence?
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

[mike regish]

If there's a plane in front of you, or anywhere around you, there's wake
turbulence. If you don't get trashed by it, you've avoided it.

mike

"Mxsmanic" > wrote in message
...
> Gary writes:
>
>> Couldn't be more wrong. In real life, you most certainly know when
>> you succeed in avoiding wake turbulence.
>
> No, you don't. You don't know if you avoided it, or if it simply wasn't
> there
> to begin with.
>
> In any case, avoidance is the only safe procedure. Trying to fly in wake
> turbulence isn't a good idea.
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

[mike regish]

eye'm purty shoor meye eye que iz ovur atey.

meyeke

"Nomen Nescio" > wrote in message
...
> -----BEGIN PGP SIGNED MESSAGE-----
>
> From: Mxsmanic >
>
>>I'm always surprised by posts that simply say "wrong," but don't explain
>>why.
>
> That's 'cause nobody with an IQ over 80 gives a **** about explaining
> ANYTHING to you.
> A simple answer of "WRONG" will help keep someone who is really trying
> to learn about flying from giving your bull**** any credibility.
>
> I would suggest substituting "IDIOT" for "wrong". It's much more
> descriptive
> of you.
>
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>

[Mxsmanic]

mike regish writes:

> A sign of a well executed 360 is to encounter your own wake turbulence,
> although the vortex generally sinks some in the intervening time and the
> turbulence is usually no more than a slight bump.

From my back-of-envelope calculations, if it's a two-minute turn, the downwash
and vortices would have descended by some 2000 feet or so by the time you
close the circle (depending on various factors). I'm surprised that there
would be anything to feel if you are maintaining the same altitude, which is
why I didn't consider this. However, if it has actually happened to you, I'll
have to review my calculations.

Anyway, while it might be interesting in real life, it would be horrifically
CPU-intensive to simulate, since it would require modeling of large chunks of
air away from the aircraft, which is as compute-bound as weather reporting.

Indeed, modeling any sort of wake turbulence would be this way, unless the
simulation were canned and provided as a couple of fixed scenarios that
wouldn't require calculation of air movements. But then you have to wonder if
it would be worthwhile, either, since it's a really bad idea to fly through
another aircraft's wake turbulence. If it's mild there's not much to
simulate; if it's heavy it's too dangerous to approach.

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[Peter Dohm]

"Mxsmanic" > wrote in message
...
> mike regish writes:
>
> > A sign of a well executed 360 is to encounter your own wake turbulence,
> > although the vortex generally sinks some in the intervening time and the
> > turbulence is usually no more than a slight bump.
>
> From my back-of-envelope calculations, if it's a two-minute turn, the
downwash
> and vortices would have descended by some 2000 feet or so by the time you
> close the circle (depending on various factors). I'm surprised that there
> would be anything to feel if you are maintaining the same altitude, which
is
> why I didn't consider this. However, if it has actually happened to you,
I'll
> have to review my calculations.
>
> Anyway, while it might be interesting in real life, it would be
horrifically
> CPU-intensive to simulate, since it would require modeling of large chunks
of
> air away from the aircraft, which is as compute-bound as weather
reporting.
>
> Indeed, modeling any sort of wake turbulence would be this way, unless the
> simulation were canned and provided as a couple of fixed scenarios that
> wouldn't require calculation of air movements. But then you have to
wonder if
> it would be worthwhile, either, since it's a really bad idea to fly
through
> another aircraft's wake turbulence. If it's mild there's not much to
> simulate; if it's heavy it's too dangerous to approach.
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

That's a keeper.

[swag]

This is actually a maneuver that's demonstrated and practiced very
early in flight training, so I'm sure all pilots and student pilots
have experienced this. But your calculations are fairly correnct--a 2
minute turn won't cut it. It's usually demonstrated with a 60 degree
bank turn. I'm not sure of the timing, but i'd guess 30 sec or less.

On Apr 14, 7:11 am, Mxsmanic > wrote:
> mike regish writes:
> > A sign of a well executed 360 is to encounter your own wake turbulence,
> > although the vortex generally sinks some in the intervening time and the
> > turbulence is usually no more than a slight bump.
>
> From my back-of-envelope calculations, if it's a two-minute turn, the downwash
> and vortices would have descended by some 2000 feet or so by the time you
> close the circle (depending on various factors). I'm surprised that there
> would be anything to feel if you are maintaining the same altitude, which is
> why I didn't consider this. However, if it has actually happened to you, I'll
> have to review my calculations.
>
> Anyway, while it might be interesting in real life, it would be horrifically
> CPU-intensive to simulate, since it would require modeling of large chunks of
> air away from the aircraft, which is as compute-bound as weather reporting.
>
> Indeed, modeling any sort of wake turbulence would be this way, unless the
> simulation were canned and provided as a couple of fixed scenarios that
> wouldn't require calculation of air movements. But then you have to wonder if
> it would be worthwhile, either, since it's a really bad idea to fly through
> another aircraft's wake turbulence. If it's mild there's not much to
> simulate; if it's heavy it's too dangerous to approach.
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

[Snowbird]

"Mxsmanic" wrote ...

> From my back-of-envelope calculations, if it's a two-minute turn, the
> downwash
> and vortices would have descended by some 2000 feet or so by the time you
> close the circle (depending on various factors). I'm surprised that there
> would be anything to feel if you are maintaining the same altitude, which
> is
> why I didn't consider this. However, if it has actually happened to you,
> I'll
> have to review my calculations.
>
Tip vortices is not the only form of turbulence behind an aircraft. And an
airliner on approach has a different type of wake than a trainer at
altitude.

> Anyway, while it might be interesting in real life, it would be
> horrifically
> CPU-intensive to simulate, since it would require modeling of large chunks
> of
> air away from the aircraft, which is as compute-bound as weather
> reporting.
>
> Indeed, modeling any sort of wake turbulence would be this way, unless the
> simulation were canned and provided as a couple of fixed scenarios that
> wouldn't require calculation of air movements. But then you have to
> wonder if
> it would be worthwhile, either, since it's a really bad idea to fly
> through
> another aircraft's wake turbulence. If it's mild there's not much to
> simulate; if it's heavy it's too dangerous to approach.
>
The best value of a good simulator is that it enables training of situations
that would be unsafe to do in a real aircraft.Flying into wake turbulence is
a good example.

[Judah]

"swag" > wrote in
ups.com:

> This is actually a maneuver that's demonstrated and practiced very
> early in flight training, so I'm sure all pilots and student pilots
> have experienced this. But your calculations are fairly correnct--a 2
> minute turn won't cut it. It's usually demonstrated with a 60 degree
> bank turn. I'm not sure of the timing, but i'd guess 30 sec or less.

You meant 45 degree bank. A 60 degree steep turn would require a parachute.

[Mxsmanic]

swag writes:

> This is actually a maneuver that's demonstrated and practiced very
> early in flight training, so I'm sure all pilots and student pilots
> have experienced this. But your calculations are fairly correnct--a 2
> minute turn won't cut it. It's usually demonstrated with a 60 degree
> bank turn. I'm not sure of the timing, but i'd guess 30 sec or less.

Don't you have to descend to catch the wake? Downwash should be moving
downward at a few knots and IIRC the vortices do as well, so after two minutes
at, say, 12 knots, the turbulence would be almost 2500 feet below you, if you
are staying at altitude. I don't see how you could run into it.

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[Mxsmanic]

swag writes:

> This is actually a maneuver that's demonstrated and practiced very
> early in flight training, so I'm sure all pilots and student pilots
> have experienced this. But your calculations are fairly correnct--a 2
> minute turn won't cut it. It's usually demonstrated with a 60 degree
> bank turn. I'm not sure of the timing, but i'd guess 30 sec or less.

Sorry, I didn't notice the 60-degree part. Sixty degrees would be 2.7 Gs,
which seems high for a GA aircraft. If I'm not mistaken, this would allow a
360-degree turn in about one minute at 100 kts. Still, the wake would be a
thousand feet lower or so by then (assuming a 12-kt downwash).

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[Mxsmanic]

Snowbird writes:

> Tip vortices is not the only form of turbulence behind an aircraft. And an
> airliner on approach has a different type of wake than a trainer at
> altitude.

All of them should be moving downward, though. Which means that if you try to
catch your own wake at constant altitude, you should miss it, as it will have
drifted downward. Or am I missing something?

> The best value of a good simulator is that it enables training of situations
> that would be unsafe to do in a real aircraft.Flying into wake turbulence is
> a good example.

But flying into wake turbulence can flip your aircraft onto the ground. Is
that really worth practicing? You should be avoiding it instead.

Rather like the logic that says that it's better to train at avoiding spins
than to train at recovering from them.

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[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> swag writes:

> > This is actually a maneuver that's demonstrated and practiced very
> > early in flight training, so I'm sure all pilots and student pilots
> > have experienced this. But your calculations are fairly correnct--a 2
> > minute turn won't cut it. It's usually demonstrated with a 60 degree
> > bank turn. I'm not sure of the timing, but i'd guess 30 sec or less.

> Don't you have to descend to catch the wake? Downwash should be moving
> downward at a few knots and IIRC the vortices do as well, so after two minutes
> at, say, 12 knots, the turbulence would be almost 2500 feet below you, if you
> are staying at altitude. I don't see how you could run into it.

Real people in real airplanes training to become real pilots do real
45 degree bank, constant altitude turns on a regular basis and run into
their real wake.

It is just another thing you don't understand because you have no
context.

--
Jim Pennino

Remove .spam.sux to reply.

[Snowbird]

"Mxsmanic" wrote ..
>
>> Tip vortices is not the only form of turbulence behind an aircraft. And
>> an
>> airliner on approach has a different type of wake than a trainer at
>> altitude.
>
> All of them should be moving downward, though.

Do you have a reference saying this is always the case?

> Which means that if you try to
> catch your own wake at constant altitude, you should miss it, as it will
> have
> drifted downward. Or am I missing something?

Maybe the propwash?

>
>> The best value of a good simulator is that it enables training of
>> situations
>> that would be unsafe to do in a real aircraft.Flying into wake turbulence
>> is
>> a good example.
>
> But flying into wake turbulence can flip your aircraft onto the ground.
> Is
> that really worth practicing? You should be avoiding it instead.
>
> Rather like the logic that says that it's better to train at avoiding
> spins
> than to train at recovering from them.
>

The opposite logic is quite popular too. In fact this has been debated
almost as long as aviation.
Personally, I'd welcome a simulator accurate enough to practice recovery
from a wake encounter. The same goes for spin recovery.

[[email protected]]

In rec.aviation.piloting swag > wrote:
> This is actually a maneuver that's demonstrated and practiced very
> early in flight training, so I'm sure all pilots and student pilots
> have experienced this. But your calculations are fairly correnct--a 2
> minute turn won't cut it. It's usually demonstrated with a 60 degree
> bank turn. I'm not sure of the timing, but i'd guess 30 sec or less.

It is 45 degrees +/- 5 for private, 50 +/- 5 for commercial.

--
Jim Pennino

Remove .spam.sux to reply.

[mike regish]

no it wouldn't

mike

>
> You meant 45 degree bank. A 60 degree steep turn would require a
> parachute.

[Maxwell]

"Mxsmanic" > wrote in message
...
> swag writes:
>
>> This is actually a maneuver that's demonstrated and practiced very
>> early in flight training, so I'm sure all pilots and student pilots
>> have experienced this. But your calculations are fairly correnct--a 2
>> minute turn won't cut it. It's usually demonstrated with a 60 degree
>> bank turn. I'm not sure of the timing, but i'd guess 30 sec or less.
>
> Sorry, I didn't notice the 60-degree part. Sixty degrees would be 2.7 Gs,
> which seems high for a GA aircraft. If I'm not mistaken, this would allow
> a
> 360-degree turn in about one minute at 100 kts. Still, the wake would be
> a
> thousand feet lower or so by then (assuming a 12-kt downwash).
>

Your calculations are as insane as you are, guess again.
What you are MISSING is well beyond the scope this newsgroup, much less this
topic.
Sixty degrees turns are part of routine PPL training, without a parachute.
Check the regs you so often quote with implied authority.
Finding your own wake turbulence while doing 60/360s happens every day, and
is most often demonstrated by every CFI.
Descending 360 turns are executed routinely by pilots needing to descend
without leaving an area, such as descending to land after crossing high
mountains.

You demonstrate daily that you are incompetent to comprehend the answers to
the questions you pose, and regardless of your motives, based on your own
lack of experience, you serve no more purpose here than a common troll.

Get a life,,, or make time and money for a few measly flight hours.

[Mxsmanic]

mike regish writes:

> no it wouldn't

If it's exactly 60 degrees, it wouldn't. Beyond 60 degrees, however, a
parachute is required. See FAR 91.307(c)(1).

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Thomas Borchert]

Mxsmanic,

> Or am I missing something?
>

Life?

--
Thomas Borchert (EDDH)

[Thomas Borchert]

Mxsmanic,

> Sixty degrees would be 2.7 Gs,
>

GO AWAY!

--
Thomas Borchert (EDDH)

[Mxsmanic]

writes:

> Real people in real airplanes training to become real pilots do real
> 45 degree bank, constant altitude turns on a regular basis and run into
> their real wake.

My research indicates that this is not possible. The wake sinks at a rate
between 150 and 500 feet per minute (roughly). Thus, it would always be well
below the airplane by the time it closes its own circle, unless the airplane
is also descending.

I've seen reports of pilots descending in a 360-degree turn and running into
their own wakes. If they can descend and encounter their own wake, then they
cannot remain at the same altitude and encounter it. It cannot be in two
places at once.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Little Endian]

> Sorry, I didn't notice the 60-degree part. Sixty degrees would be 2.7 Gs,

Incorrect statement. Sixty degrees would be 2 Gs.

[Mxsmanic]

Snowbird writes:

> Do you have a reference saying this is always the case?

Every reference I've checked says so. They sink at a variable rate, but
usually at least 150-200 feet per minute, sometimes much more.

They have to do this, because it is the reaction to forcing the downwash
downward that produces lift.

> Maybe the propwash?

I'd expect the propwash to be drawn down with the downwash, but I'm not sure.
I would not expect the propwash to be significant after two minutes.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> writes:

> > Real people in real airplanes training to become real pilots do real
> > 45 degree bank, constant altitude turns on a regular basis and run into
> > their real wake.

> My research indicates that this is not possible.

Your research at what, at your desk in front of Microsoft Flight
Simulator?

In my experience as a real pilot of real airplanes, it has happened.

In the experience of many real pilots of real airplanes, it has happened.

The altitude tolerance on a 360 degree turn is +/- 100 feet from
start to finish.

Once again, you have no context for understanding.

<snip ignorant nonsense>

--
Jim Pennino

Remove .spam.sux to reply.

[Bertie the Bunyip]

On Apr 13, 8:04 am, Mxsmanic > wrote:
> Snowbird writes:
> > How does MS flight simulator simulate the symptoms of hypoxia?
>
> No provision is made for simulation of hypoxia of altitude. If the aircraft
> is accelerated, the simulator does simulate the visual effects of positive and
> negative Gs.
>

No it doesn´t you moron.


Bertie

[Bertie the Bunyip]

On Apr 14, 7:18 pm, Mxsmanic > wrote:
> Snowbird writes:
> > Do you have a reference saying this is always the case?
>
> Every reference I've checked says so. They sink at a variable rate, but
> usually at least 150-200 feet per minute, sometimes much more.
>
> They have to do this, because it is the reaction to forcing the downwash
> downward that produces lift.
>
> > Maybe the propwash?
>
> I'd expect the propwash to be drawn down with the downwash, but I'm not sure.
> I would not expect the propwash to be significant after two minutes.

Good grief.


Bertie

[Bertie the Bunyip]

On Apr 14, 7:16 pm, Mxsmanic > wrote:
> writes:
> > Real people in real airplanes training to become real pilots do real
> > 45 degree bank, constant altitude turns on a regular basis and run into
> > their real wake.
>
> My research indicates that this is not possible. The wake sinks at a rate
> between 150 and 500 feet per minute (roughly). Thus, it would always be well
> below the airplane by the time it closes its own circle, unless the airplane
> is also descending.
>
> I've seen reports of pilots descending in a 360-degree turn and running into
> their own wakes. If they can descend and encounter their own wake, then they
> cannot remain at the same altitude and encounter it. It cannot be in two
> places at once.
>

You´re an idiot.


Bertie

[Maxwell]

"Mxsmanic" > wrote in message
...
> Snowbird writes:
>
>> How does MS flight simulator simulate the symptoms of hypoxia?
>
> No provision is made for simulation of hypoxia of altitude. If the
> aircraft
> is accelerated, the simulator does simulate the visual effects of positive
> and
> negative Gs.
>

The VISUAL effects of positive and negative Gs. Priceless!

Lay off the simulated hypoxia sauce, you moron. You need to loose some
simiulated altitude real fast.

[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> Snowbird writes:

> > Do you have a reference saying this is always the case?

> Every reference I've checked says so. They sink at a variable rate, but
> usually at least 150-200 feet per minute, sometimes much more.

> They have to do this, because it is the reaction to forcing the downwash
> downward that produces lift.

> > Maybe the propwash?

> I'd expect the propwash to be drawn down with the downwash, but I'm not sure.
> I would not expect the propwash to be significant after two minutes.

What you expect and what really happens in real airplanes are obviously
two different things.

Any object in the air with an airspeed greater than zero has wake
turbulance.

The precise details of that turbulance depend upon the shape of the
object, the speed of the object, and the condition of the surrounding
air.

The wake turbulance of transport category aircraft has been widely
studied because such turbulance is dangerous to other aircraft.

The wake turbulance of light aircraft has not been studied to such
a degree, if at all, because the worst that happens when you fly
through it is you experience a little bump, i.e. no one cares
about it.

Therefor, it is highly unlikely that you will be able to find any
information on the typical characteristics of the wake turbulance
generated by a Cessna 182, or any other GA aircraft other than from
the experiences of real pilots.

--
Jim Pennino

Remove .spam.sux to reply.

[Bertie the Bunyip]

On Apr 14, 6:05 pm, Mxsmanic > wrote:
> Snowbird writes:
> > Tip vortices is not the only form of turbulence behind an aircraft. And an
> > airliner on approach has a different type of wake than a trainer at
> > altitude.
>
> All of them should be moving downward, though. Which means that if you try to
> catch your own wake at constant altitude, you should miss it, as it will have
> drifted downward. Or am I missing something?
>
> > The best value of a good simulator is that it enables training of situations
> > that would be unsafe to do in a real aircraft.Flying into wake turbulence is
> > a good example.
>
> But flying into wake turbulence can flip your aircraft onto the ground. Is
> that really worth practicing? You should be avoiding it instead.
>
> Rather like the logic that says that it's better to train at avoiding spins
> than to train at recovering from them.

It´s the same training fjukktard



bertie

[Mxsmanic]

writes:

> Your research at what, at your desk in front of Microsoft Flight
> Simulator?

No, my survey of the literature.

> In my experience as a real pilot of real airplanes, it has happened.
>
> In the experience of many real pilots of real airplanes, it has happened.

In the course of my research, it appears to be impossible. The sources I
consulted seemed more reliable than a name on a screen.

> The altitude tolerance on a 360 degree turn is +/- 100 feet from
> start to finish.

If you are not descending at the same speed as your wake, I don't see how you
can run back into it.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Mxsmanic]

Maxwell writes:

> Sixty degrees turns are part of routine PPL training, without a parachute.

Training is exempt from the parachute requirement.

> Check the regs you so often quote with implied authority.

I've already pointed to them, and if you had looked at them yourself, you
would have seen the exemption for training.

> Finding your own wake turbulence while doing 60/360s happens every day, and
> is most often demonstrated by every CFI.

At constant altitude?

> Descending 360 turns are executed routinely by pilots needing to descend
> without leaving an area, such as descending to land after crossing high
> mountains.

Ah ... descending turns are different, and you might well enounter your own
wake in that case.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Judah]

Mxsmanic > wrote in
:

> Don't you have to descend to catch the wake? Downwash should be moving
> downward at a few knots and IIRC the vortices do as well, so after two
> minutes at, say, 12 knots, the turbulence would be almost 2500 feet
> below you, if you are staying at altitude. I don't see how you could
> run into it.

I'm not a physicist, but I suspect your calculations are missing several
factors, including (but not limited to) some that I can point out:

1) At a 45 degree bank, the wings are not actually pointed directly down.

2) In the typical trainer plane flying 100 knots, a 45 degree bank turn
will take far less than 2 minutes to go 360 degrees.

3) Wind can blow the wake in any number of directions, including up, and
including into the path of the 360 degree turn.

The bottom line is that the Practical Test Standards call for pilots to
perform a manuever called a Steep Turn of 360 degrees at a bank angle of 45
degrees. Every certificated pilot practices this, and demonstrates it to an
examiner, and frequently demonstrates it again during his or her Biannual
Flight Review.

Do you think it is more likely that the pilots on this newsgroup who
express that they have flown through their own wake while performing this
manuever are just lying to you?

Or perhaps you have miscalculated or omitted something from your
calculations.

[Maxwell]

"Mxsmanic" > wrote in message
...
> Maxwell writes:
>
>> Sixty degrees turns are part of routine PPL training, without a
>> parachute.
>
> Training is exempt from the parachute requirement.
>
>> Check the regs you so often quote with implied authority.
>
> I've already pointed to them, and if you had looked at them yourself, you
> would have seen the exemption for training.
>
>> Finding your own wake turbulence while doing 60/360s happens every day,
>> and
>> is most often demonstrated by every CFI.
>
> At constant altitude?
>
>> Descending 360 turns are executed routinely by pilots needing to descend
>> without leaving an area, such as descending to land after crossing high
>> mountains.
>
> Ah ... descending turns are different, and you might well enounter your
> own
> wake in that case.
>

All your answers are either wrong or negligently incomplete. You ZEROed this
one too!

[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> writes:

> > Your research at what, at your desk in front of Microsoft Flight
> > Simulator?

> No, my survey of the literature.

What does your "literature" say about the wake turbulance to be
found from a Cessna 172? How about a '47 Ercoupe?

> > In my experience as a real pilot of real airplanes, it has happened.
> >
> > In the experience of many real pilots of real airplanes, it has happened.

> In the course of my research, it appears to be impossible. The sources I
> consulted seemed more reliable than a name on a screen.

I, and many, many other pilots have experienced it.

Yet another difference between simulated and real flight.

> > The altitude tolerance on a 360 degree turn is +/- 100 feet from
> > start to finish.

> If you are not descending at the same speed as your wake, I don't see how you
> can run back into it.

Because you have no context with which to even begin to understand it.

All your protestations do is show how unrealistic your flight simulator
and "experience" gained through playing flight simulator is.

--
Jim Pennino

Remove .spam.sux to reply.

[mike regish]

we weren't talking about beyond 60 degrees.

mike

"Mxsmanic" > wrote in message
...
> mike regish writes:
>
>> no it wouldn't
>
> If it's exactly 60 degrees, it wouldn't. Beyond 60 degrees, however, a
> parachute is required. See FAR 91.307(c)(1).
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

[mike regish]

If the local air mass is rising, it will slow the sink or even raise the
vortex.

mike

"Mxsmanic" > wrote in message
...
> writes:
>
>> Real people in real airplanes training to become real pilots do real
>> 45 degree bank, constant altitude turns on a regular basis and run into
>> their real wake.
>
> My research indicates that this is not possible. The wake sinks at a rate
> between 150 and 500 feet per minute (roughly). Thus, it would always be
> well
> below the airplane by the time it closes its own circle, unless the
> airplane
> is also descending.
>
> I've seen reports of pilots descending in a 360-degree turn and running
> into
> their own wakes. If they can descend and encounter their own wake, then
> they
> cannot remain at the same altitude and encounter it. It cannot be in two
> places at once.
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

[mike regish]

rong

mik

"Nomen Nescio" > wrote in message
...
> -----BEGIN PGP SIGNED MESSAGE-----
>
> From: "mike regish" >
>
>>eye'm purty shoor meye eye que iz ovur atey.
>
> Wel mebbee U is a slo lerner.
> Eeder dat or U liv in Northampton.
>
> -----BEGIN PGP SIGNATURE-----
> Version: N/A
>
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>
>

[george]

On Apr 15, 6:25 am, wrote:
> In rec.aviation.piloting Mxsmanic > wrote:
>
> > writes:
> > > Your research at what, at your desk in front of Microsoft Flight
> > > Simulator?
> > No, my survey of the literature.
>
> What does your "literature" say about the wake turbulance to be
> found from a Cessna 172? How about a '47 Ercoupe?
>
> > > In my experience as a real pilot of real airplanes, it has happened.
>
> > > In the experience of many real pilots of real airplanes, it has happened.
> > In the course of my research, it appears to be impossible. The sources I
> > consulted seemed more reliable than a name on a screen.
>
> I, and many, many other pilots have experienced it.
>
> Yet another difference between simulated and real flight.
>
> > > The altitude tolerance on a 360 degree turn is +/- 100 feet from
> > > start to finish.
> > If you are not descending at the same speed as your wake, I don't see how you
> > can run back into it.
>
> Because you have no context with which to even begin to understand it.
>
> All your protestations do is show how unrealistic your flight simulator
> and "experience" gained through playing flight simulator is.
>

I always maintained altitude and rate of turn in steep turns with the
end result being hitting my own slipstream.
Its time mixup got into an aeroplane

[Thomas Borchert]

Mxsmanic,

> In the course of my research, it appears to be impossible. The sources I
> consulted seemed more reliable than a name on a screen.
>

Then what are you doing here?


--
Thomas Borchert (EDDH)

[Thomas Borchert]

Mxsmanic,

> My research indicates that this is not possible.
>

Hoho! Well then, I guess us pilots who routinely encounter this, e.g.
during something as mundane as a rental checkout, must all be
delusional.

--
Thomas Borchert (EDDH)

[EridanMan]

ROFL... Wow... Jay... you owe me a new keyboard! ;)

Now we just need to put together a # of drinks for altitude table and
bingo, instant Hypoxia support for MSFS;)

[Sylvain]

Mxsmanic wrote:
> Sorry, I didn't notice the 60-degree part. Sixty degrees would be 2.7 Gs,

nope, at 60 degrees you got yourself 2Gs; about 1.4Gs at 45 degrees.

So... you might want to go over your calculations again.

--Sylvain

[ManhattanMan]

george wrote:
>
> I always maintained altitude and rate of turn in steep turns with the
> end result being hitting my own slipstream.
> Its time mixup got into an aeroplane

Who'd cleanup the vomit and brown runny stuff??? d:->))

[Sylvain]

Mxsmanic wrote:

> Every reference I've checked says so. They sink at a variable rate, but
> usually at least 150-200 feet per minute, sometimes much more.

Note that we were talking about turns at either 45 or 60 degrees bank; with
a typical trainer flying at, say 90 or 100 knots, a 360 would be completed
under say, 35 or 20 seconds respectively. Now, if your numbers of 200
feet per minute are correct (and don't take it personally if I have my
doubts), the turbulence would have gone down, by about 115 and 67 feet
respectively. Considering that the acceptable range of error in the PTS
for a private certificate is +/- 100 feet (for a 45 degrees of bank), it
is indeed possible to bump into your own turbulence, even using your
numbers.

--Sylvain

[A Guy Called Tyketto]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

In rec.aviation.piloting Mxsmanic > wrote:
>
>> In my experience as a real pilot of real airplanes, it has happened.
>>
>> In the experience of many real pilots of real airplanes, it has happened.
>
> In the course of my research, it appears to be impossible. The sources I
> consulted seemed more reliable than a name on a screen.

Pathetic, to say the least.

If you're doing such research, why don't you play devil's
advocate to make sure that your 'research' is right, and compare the
'names on a screen' to what is listed in the person's profile for their
log, hours flown, experience, how long they've had their tickets, etc.

However, since that is also just a 'name on a screen', with
your M.O. it is safe to assume you wouldn't count that as reliable
either.

In the end, all your research is put up by a 'name on a screen';
therefore, you can't trust that to be any more reliable than the people
here.

Your research, and your logic behind doing such research, is
flawed.

BL.
- --
Brad Littlejohn | Email:
Unix Systems Administrator, |
Web + NewsMaster, BOFH.. Smeghead! :) | http://www.wizard.com/~tyketto
PGP: 1024D/E319F0BF 6980 AAD6 7329 E9E6 D569 F620 C819 199A E319 F0BF

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[Peter Dohm]

"Mxsmanic" > wrote in message
...
> swag writes:
>
> > This is actually a maneuver that's demonstrated and practiced very
> > early in flight training, so I'm sure all pilots and student pilots
> > have experienced this. But your calculations are fairly correnct--a 2
> > minute turn won't cut it. It's usually demonstrated with a 60 degree
> > bank turn. I'm not sure of the timing, but i'd guess 30 sec or less.
>
> Don't you have to descend to catch the wake? Downwash should be moving
> downward at a few knots and IIRC the vortices do as well, so after two
minutes
> at, say, 12 knots, the turbulence would be almost 2500 feet below you, if
you
> are staying at altitude. I don't see how you could run into it.
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

Wakes are complex in their action. Consistently cutting your own wake in
360s and figure 8s is a mark of good technique--and the altimeter reading
will remain unchanged.

Since they are covered extensively in both flight and ground instruction,
there seems little need here.

Peter

[Peter Dohm]

"Mxsmanic" > wrote in message
...
> swag writes:
>
> > This is actually a maneuver that's demonstrated and practiced very
> > early in flight training, so I'm sure all pilots and student pilots
> > have experienced this. But your calculations are fairly correnct--a 2
> > minute turn won't cut it. It's usually demonstrated with a 60 degree
> > bank turn. I'm not sure of the timing, but i'd guess 30 sec or less.
>
> Sorry, I didn't notice the 60-degree part. Sixty degrees would be 2.7 Gs,
> which seems high for a GA aircraft. If I'm not mistaken, this would allow
a
> 360-degree turn in about one minute at 100 kts. Still, the wake would be
a
> thousand feet lower or so by then (assuming a 12-kt downwash).
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

2.00 Gs

[Judah]

Mxsmanic > wrote in
:

> In the course of my research, it appears to be impossible. The sources
> I consulted seemed more reliable than a name on a screen.

If you write the names on the screen down on a piece of paper, the two
sources will become equally anonymous, then.

[Mxsmanic]

mike regish writes:

> If the local air mass is rising, it will slow the sink or even raise the
> vortex.

And it will raise the aircraft, too, so the result is the same.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Mxsmanic]

Judah writes:

> 1) At a 45 degree bank, the wings are not actually pointed directly down.

Even at a 45-degree bank, the wake will still descend (and it will also move
outward, making it hard to catch as well).

> 3) Wind can blow the wake in any number of directions, including up, and
> including into the path of the 360 degree turn.

But it will blow the aircraft in the same direction. The wake will still
descend relative to the aircraft.

> Do you think it is more likely that the pilots on this newsgroup who
> express that they have flown through their own wake while performing this
> manuever are just lying to you?

No. I think they just don't realize that they were descending when they
caught their own wakes.

> Or perhaps you have miscalculated or omitted something from your
> calculations.

I didn't calculate much; I just looked things up. Without exception, every
source says that the wake descends. And it has to, since that's the only way
to keep the aircraft flying.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Mxsmanic]

Sylvain writes:

> Note that we were talking about turns at either 45 or 60 degrees bank; with
> a typical trainer flying at, say 90 or 100 knots, a 360 would be completed
> under say, 35 or 20 seconds respectively. Now, if your numbers of 200
> feet per minute are correct (and don't take it personally if I have my
> doubts), the turbulence would have gone down, by about 115 and 67 feet
> respectively. Considering that the acceptable range of error in the PTS
> for a private certificate is +/- 100 feet (for a 45 degrees of bank), it
> is indeed possible to bump into your own turbulence, even using your
> numbers.

If they descend, yes. QED.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Mxsmanic]

Maxwell writes:

> The VISUAL effects of positive and negative Gs.

Vision goes first when a pilot experiences positive Gs. It goes dark. The
simulator darkens the screen when this happens.

The simulator does the same for redouts with negative Gs. The first time I
saw it, it took a while to figure out what it was. It only happens in
high-performance aircraft such as the Extra 300s, because small GA aircraft
and jetliners simply can't reach those accelerations without breaking up.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Thomas Borchert]

Mxsmanic,

> If they descend, yes. QED.
>

Put some research effort into what QED means. You haven't proven
anything.

--
Thomas Borchert (EDDH)

[mike regish]

Don't forget that when you are making a steep turn, your vortices are not
sinking straight down. They are sinking perpindicular to your wings. I would
also guess, this IS just a guess though, that vortices sink at the lower end
of the range of sink rates you'll see given.

I've hit the wake in otherwise smooth air without showing any loss of
altitude in the turn. Since it's invisible, I can't say with absolute
certainty that it was my own wake, but it sure was the best explanation I
could come up with.

mike

"Mxsmanic" > wrote in message
...

> Ah ... descending turns are different, and you might well enounter your
> own
> wake in that case.
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

[mike regish]

Not if you are maintaining altitude via altimeter.

mike

"Mxsmanic" > wrote in message
...
> mike regish writes:
>
>> If the local air mass is rising, it will slow the sink or even raise the
>> vortex.
>
> And it will raise the aircraft, too, so the result is the same.
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

[mike regish]

Add "for small aircraft" after "sink rates you'll see given."

mike

"mike regish" > wrote in message
. ..

> Don't forget that when you are making a steep turn, your vortices are not
> sinking straight down. They are sinking perpindicular to your wings. I
> would also guess, this IS just a guess though, that vortices sink at the
> lower end of the range of sink rates you'll see given.

[Viperdoc[_4_]]

I've done the same many times as well, both circling as well as in loops. In
an aerobatic plane with the smoke on it is easier to see your flight path of
course, which makes it easier and more fun.

This is just another example of book knowledge versus reality and
experience.

[mike regish]

But, mx's assumptions about vortices sinking is essentially correct. He just
doesn't understand that sometimes conditions combine to make hitting your
own wake very possible.

mike

"Viperdoc" > wrote in message
...
> I've done the same many times as well, both circling as well as in loops.
> In an aerobatic plane with the smoke on it is easier to see your flight
> path of course, which makes it easier and more fun.
>
> This is just another example of book knowledge versus reality and
> experience.
>

[Bertie the Bunyip]

On Apr 15, 9:18 am, Mxsmanic > wrote:
> Maxwell writes:
> > The VISUAL effects of positive and negative Gs.
>
> Vision goes first when a pilot experiences positive Gs. It goes dark. The
> simulator darkens the screen when this happens.
>
> The simulator does the same for redouts with negative Gs. The first time I
> saw it, it took a while to figure out what it was. It only happens in
> high-performance aircraft such as the Extra 300s, because small GA aircraft
> and jetliners simply can't reach those accelerations without breaking up.

Yes, they can, fjukkwit.

Wrong again..



Don´t you ever get tired of being wrong?



Bertie

[Bertie the Bunyip]

On Apr 14, 3:44 am, Mxsmanic > wrote:
> Gary writes:
> > Couldn't be more wrong. In real life, you most certainly know when
> > you succeed in avoiding wake turbulence.
>
> No, you don't. You don't know if you avoided it, or if it simply wasn't there
> to begin with.
>

Good lord you´re thick.

Bertie

[Judah]

Mxsmanic > wrote in
:

> Even at a 45-degree bank, the wake will still descend (and it will also
> move outward, making it hard to catch as well).

What is the wingspan of the aircraft?

> But it will blow the aircraft in the same direction. The wake will
> still descend relative to the aircraft.

The aircraft is powered. It need not follow the wind alone.

> No. I think they just don't realize that they were descending when they
> caught their own wakes.

Altimeters make this less likely than you might believe. Perhaps you are the
one that doesn't realize something. As you admit below, you didn't put much
thought into your determination.

> I didn't calculate much; I just looked things up. Without exception,
> every source says that the wake descends. And it has to, since that's
> the only way to keep the aircraft flying.

[Mxsmanic]

Judah writes:

> What is the wingspan of the aircraft?

The wingspan shouldn't matter.

> Altimeters make this less likely than you might believe. Perhaps you are the
> one that doesn't realize something. As you admit below, you didn't put much
> thought into your determination.

To convince me, I need an explanation of why wakes descend universally except
by some magic exception when someone is doing a 360-degree turn.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Thomas Borchert]

Mxsmanic,

> To convince me,
>

What, exactly, do you think this group could possibly gain by even
trying to convince you?

--
Thomas Borchert (EDDH)

[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> mike regish writes:

> > If the local air mass is rising, it will slow the sink or even raise the
> > vortex.

> And it will raise the aircraft, too, so the result is the same.

Except in a real airplane with a real pilot, the pilot is maintaining
altitude +/- 100 feet.

--
Jim Pennino

Remove .spam.sux to reply.

[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> Judah writes:

> > What is the wingspan of the aircraft?

> The wingspan shouldn't matter.

> > Altimeters make this less likely than you might believe. Perhaps you are the
> > one that doesn't realize something. As you admit below, you didn't put much
> > thought into your determination.

> To convince me, I need an explanation of why wakes descend universally except
> by some magic exception when someone is doing a 360-degree turn.

Why in the world would anyone bother to do anything other than to tell
you it has, in fact, happened to them?

If you feel some need to be convinced you are full of crap, turn off the
computer, get off your ass, and go fly in a real airplane and observe
it for yourself.

--
Jim Pennino

Remove .spam.sux to reply.

[Judah]

Mxsmanic > wrote in
:

> The wingspan shouldn't matter.

I haven't studied geometry in a long time, but simple geometry would dictate
that at a 45 degree angle, vortices generated by the higher wing would
naturally need to fall some distance before they could not be intercepted by
the lower wing.

> To convince me, I need an explanation of why wakes descend universally
> except by some magic exception when someone is doing a 360-degree turn.

I am not able to explain to you the scientific principles behind why I have
observed what I have observed. I can only tell you that I have observed it,
as have numerous other pilots, and the fact that you don't believe me is your
problem, not mine.

[Rip]

Judah, one of his problems is that he fixates on insufficient
information, and then gets frustrated when his assumptions are
incorrect. Obviously, MX can only concieve of downwash generated by the
wings as they create lift. Apparently, he can't concieve of the UPWASH
created by the tail surfaces pushing DOWN, nor the potential for
interaction between the two, or other turbulence that may be created in
the air mass merely because a large object is plowing through it at a
high rate of speed.

Rip

[Capt. Geoffrey Thorpe]

"Rip" > wrote in message
et...
> Judah, one of his problems is that he fixates on insufficient information,
> and then gets frustrated when his assumptions are incorrect. Obviously, MX
> can only concieve of downwash generated by the wings as they create lift.
> Apparently, he can't concieve of the UPWASH created by the tail surfaces
> pushing DOWN, nor the potential for interaction between the two, or other
> turbulence that may be created in the air mass merely because a large
> object is plowing through it at a high rate of speed.
>
> Rip

Or that the wake of a Cessna 150 might not sink as fast as the wake of a
fully loaded 747...

--
Geoff
The Sea Hawk at Wow Way d0t Com
remove spaces and make the obvious substitutions to reply by mail
When immigration is outlawed, only outlaws will immigrate.

[Judah]

Rip > wrote in news:AIvUh.10078$YL5.3718
@newssvr29.news.prodigy.net:

> Judah, one of his problems is that he fixates on insufficient
> information, and then gets frustrated when his assumptions are
> incorrect.

He doesn't get frustrated. He simply denies the possibility that he is wrong
by changing the scope of the original question so he can claim he was right
all along. His ego simply won't allow him to be wrong.

It's like a disease.

> Obviously, MX can only concieve of downwash generated by the
> wings as they create lift. Apparently, he can't concieve of the UPWASH
> created by the tail surfaces pushing DOWN, nor the potential for
> interaction between the two, or other turbulence that may be created in
> the air mass merely because a large object is plowing through it at a
> high rate of speed.

I didn't think of this myself, but it certainly makes sense to me. I suspect
it will make sense to MX too, and then he will try to convince us all that
this doesn't qualify as Wake Turbulence or that he was only referring to
downwash from the wings to begin with or some other change in the scope of
his comments to make him right (at least in his own mind).

[Peter Dohm]

"Capt. Geoffrey Thorpe" <The Sea Hawk at wow way d0t com> wrote in message
news:WvWdnUKzmpUiF7_bnZ2dnUVZ_rOqnZ2d@wideopenwest .com...
> "Rip" > wrote in message
> et...
> > Judah, one of his problems is that he fixates on insufficient
information,
> > and then gets frustrated when his assumptions are incorrect. Obviously,
MX
> > can only concieve of downwash generated by the wings as they create
lift.
> > Apparently, he can't concieve of the UPWASH created by the tail surfaces
> > pushing DOWN, nor the potential for interaction between the two, or
other
> > turbulence that may be created in the air mass merely because a large
> > object is plowing through it at a high rate of speed.
> >
> > Rip
>
> Or that the wake of a Cessna 150 might not sink as fast as the wake of a
> fully loaded 747...
>
> --
Or that the tip vortices might be called that for a reason, or the effects
that might have, etc. ad infinitum.

Peter

[d.g.s.]

On 4/15/2007 1:35 PM Judah jumped down, turned around, and wrote:

> It's like a disease.

A disease ... or a syndrome?

http://en.wikipedia.org/wiki/Asperger_syndrome
http://www.aspergers.com/

It's a puzzlement.
--
dgs

[Judah]

"d.g.s." > wrote in news:58fm5hF2fkop4U1
@mid.individual.net:

> On 4/15/2007 1:35 PM Judah jumped down, turned around, and wrote:
>
>> It's like a disease.
>
> A disease ... or a syndrome?
>
> http://en.wikipedia.org/wiki/Asperger_syndrome
> http://www.aspergers.com/
>
> It's a puzzlement.

Tough to say. I think he's closer to Schizophrenia than Aspergers, but I'm
not a doctor.

For one thing, Aspergers subjects focus on a specific activity to the
exclusion of other activities. Manic, on the other hand, has demonstrated
that he can haunt several differently themed newsgroups besides just Aviation
- including Travel, Photography, and Technology newsgroups.

No, I don't think he's got Aspergers.

[DR]

Mxsmanic wrote:
> Judah writes:
>
>> What is the wingspan of the aircraft?
>
> The wingspan shouldn't matter.
>
>> Altimeters make this less likely than you might believe. Perhaps you are the
>> one that doesn't realize something. As you admit below, you didn't put much
>> thought into your determination.
>
> To convince me, I need an explanation of why wakes descend universally except
> by some magic exception when someone is doing a 360-degree turn.
>
Perhaps you are not considering all the causes of turbulence that follow
an aircraft (in it's wake)?

Cheers MarkC

[DR]

Rip wrote:
> Judah, one of his problems is that he fixates on insufficient
> information, and then gets frustrated when his assumptions are
> incorrect. Obviously, MX can only concieve of downwash generated by the
> wings as they create lift. Apparently, he can't concieve of the UPWASH
> created by the tail surfaces pushing DOWN, nor the potential for
> interaction between the two, or other turbulence that may be created in
> the air mass merely because a large object is plowing through it at a
> high rate of speed.
>
> Rip
BINGO!

Cheers MarkC

[Mxsmanic]

DR writes:

> Perhaps you are not considering all the causes of turbulence that follow
> an aircraft (in it's wake)?

Perhaps others are not considering all the causes of turbulence besides
aircraft wakes.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> DR writes:

> > Perhaps you are not considering all the causes of turbulence that follow
> > an aircraft (in it's wake)?

> Perhaps others are not considering all the causes of turbulence besides
> aircraft wakes.

You do a 360 and run into a bump when, and only when, you complete
the 360.

Invisible UFO's crossing at your exact starting point?


--
Jim Pennino

Remove .spam.sux to reply.

[Mxsmanic]

writes:

> You do a 360 and run into a bump when, and only when, you complete
> the 360.

Or you run into bumps but only notice the one that you hit when you complete
the 360.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[mike regish]

On a bumpy day you wouldn't be able to tell the wake from the overall
turbulence.

On an otherwise smooth day you can.

It can be done, Tony.

mike

"Mxsmanic" > wrote in message
...
> writes:
>
>> You do a 360 and run into a bump when, and only when, you complete
>> the 360.
>
> Or you run into bumps but only notice the one that you hit when you
> complete
> the 360.
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

[Kev]

On Apr 14, 4:27 pm, "george" > wrote:
> I always maintained altitude and rate of turn in steep turns with the
> end result being hitting my own slipstream.

As have we all on nice days, and students like to brag about it. Yet
Mx is correct, in theory we should not be able to do this.

I seem to recall recent magazine (web?) articles where the idea that
you can hit your own wake while actually holding altitude, should be
downplayed nowadays. You _have_ to descend a little bit to do so,
which means that, while you might be within the +/- 100' test
scenario, you are NOT holding the same exact altitude.

Hmm. Or else it means that the wake doesn't necessarily descend as
we're taught. On a warm clear day (which is when I've hit my own
wake), I betcha that the wake is being held upward a tiny bit by the
heat from the ground.

Cheers, Kev

[Jose]

> I seem to recall recent magazine (web?) articles where the idea that
> you can hit your own wake while actually holding altitude, should be
> downplayed nowadays. You _have_ to descend a little bit to do so,

How tall is the wake?

Jose
--
Get high on gasoline: fly an airplane.
for Email, make the obvious change in the address.

[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> writes:

> > You do a 360 and run into a bump when, and only when, you complete
> > the 360.

> Or you run into bumps but only notice the one that you hit when you complete
> the 360.

Yeah, sure.

The first time it happened to me was early in training when I was
very aware of every little bump or noise from the airplane.

As I was rolling out of the turn there was a ka-bump and my startled
reaction was a loud "What the hell was that?" which amused the
instuctor to no end.

Just because you have never experienced it and can't understand it
from your many hours of playing the Flight Simulator game doesn't
mean it doesn't exist.

It just means you don't know a whole lot about real flying or what
happens in a real airplane.

Have you ever done a short field take off in your Flight Simulator
Cessna with the springy gear and had the mains vibrate for a few
seconds shaking the airplane? It is disconserting as hell for a
low time student ready to chop power and abort take off at any
sign of a problem. Again, the instructor was amused.

--
Jim Pennino

Remove .spam.sux to reply.

[Kev]

On Apr 16, 9:41 am, Jose > wrote:
> > I seem to recall recent magazine (web?) articles where the idea that
> > you can hit your own wake while actually holding altitude, should be
> > downplayed nowadays. You _have_ to descend a little bit to do so,
>
> How tall is the wake?

Good point. Still, using the calculator at:

http://www.csgnetwork.com/aircraftturninfocalc.html

It's going to take about 30 seconds to fly a 360 steep turn at
100kts. My wake _should_ descend about 150' during that time (300
fpm). I can't imagine a C172 wake being tall enough to stay in my
way unless something else is ocurring (me descending, or the wake
staying up).

Would love to hear a decent explanation. Kev

[Jose]

> My wake _should_ descend about 150' during that time (300
> fpm). I can't imagine a C172 wake being tall enough to stay in my
> way...

I can. 150 feet is not tall at all for a wake. Remember, the air
around the wake is also being dragged by the wake vortex.

You're going to bump into something.

Jose
--
Get high on gasoline: fly an airplane.
for Email, make the obvious change in the address.

[[email protected]]

In rec.aviation.piloting Kev > wrote:
> On Apr 16, 9:41 am, Jose > wrote:
> > > I seem to recall recent magazine (web?) articles where the idea that
> > > you can hit your own wake while actually holding altitude, should be
> > > downplayed nowadays. You _have_ to descend a little bit to do so,
> >
> > How tall is the wake?

> Good point. Still, using the calculator at:

> http://www.csgnetwork.com/aircraftturninfocalc.html

> It's going to take about 30 seconds to fly a 360 steep turn at
> 100kts. My wake _should_ descend about 150' during that time (300
> fpm). I can't imagine a C172 wake being tall enough to stay in my
> way unless something else is ocurring (me descending, or the wake
> staying up).

> Would love to hear a decent explanation. Kev

Upon what do you base the assumption your wake should decend 150'?

I have never heard of any study of the wake properties of GA aircraft
and the wake of a C172 is very different than the wake of a 747 so
to extrapolate from studies of transport catagory wakes is pointless.

--
Jim Pennino

Remove .spam.sux to reply.

[Mxsmanic]

Kev writes:

> On a warm clear day (which is when I've hit my own
> wake), I betcha that the wake is being held upward a tiny bit by the
> heat from the ground.

Then you must be descending through the rising column of air.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Mxsmanic]

Jose writes:

> How tall is the wake?

The downwash is at least equal in height to the total wingspan of the
aircraft. Downwash is a large mass of air moving slowly. Still, you should
not be hitting your own wake in a 360-degree turn unless you are descending to
catch it. Oddly enough, if you are descending, the wake moves more slowly
(because you are generating less lift).

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Mxsmanic]

Jose writes:

> I can. 150 feet is not tall at all for a wake.

It's extremely tall for a small aircraft. The wake would probably be about 50
feet high.

> Remember, the air around the wake is also being dragged by the wake vortex.

But at very slow speed. Even the downwash itself is moving slowly, only a few
knots. Any of the winds that one often encounters at altitude would be enough
to rapidly disperse it.

--
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[Mxsmanic]

writes:

> Upon what do you base the assumption your wake should decend 150'?

All wakes descend; they have to, otherwise the aircraft could not stay aloft.
They move at a few knots, which still amounts to some 500 fpm.

> I have never heard of any study of the wake properties of GA aircraft
> and the wake of a C172 is very different than the wake of a 747 ...

Since you haven't heard of any study of the wake properties of GA aircraft,
you cannot possibly know whether the wake of a C172 is "very different" from
that of a 747 or not. Oops!

In fact, the general principle is the same for all aircraft wakes. They
always move downward gently. You cannot catch them in a turn unless you move
downward, too. If you are in rising air, the wake might remain stationary
relative to the ground, but then your aircraft would be rising, so you'd still
have to descend relative to the surrounding air in order to catch your wake.
And smoothly rising air isn't that common, although it's not that rare.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Mxsmanic]

mike regish writes:

> On a bumpy day you wouldn't be able to tell the wake from the overall
> turbulence.

I agree.

> On an otherwise smooth day you can.

Probably--if you actually hit it.

> It can be done, Tony.

Not without descending. The wake _must_ descend. This means that you cannot
catch it unless you descend, also. If you can explain how this rule can be
broken, I'm listening.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Mxsmanic]

writes:

> Just because you have never experienced it and can't understand it
> from your many hours of playing the Flight Simulator game doesn't
> mean it doesn't exist.

My study of aerodynamics thus far indicates that it is impossible, unless you
descend to catch your descending wake. Wakes _always_ descend. It's a
consequence of the mechanism that produces the lift that sustains the
aircraft, and it's unavoidable. Every source that I have consulted points
this out, without exception. Your mere assertion to the contrary is
completely unpersuasive in comparison.

> It just means you don't know a whole lot about real flying or what
> happens in a real airplane.

No, it means that I look at the facts, and I don't depend on the legends.

> Have you ever done a short field take off in your Flight Simulator
> Cessna with the springy gear and had the mains vibrate for a few
> seconds shaking the airplane?

I don't fly the Cessna, and I fly only at airports with hard, smooth runways
that won't bounce the aircraft around.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Maxwell]

"Kev" > wrote in message
ups.com...
> On Apr 16, 9:41 am, Jose > wrote:
>> > I seem to recall recent magazine (web?) articles where the idea that
>> > you can hit your own wake while actually holding altitude, should be
>> > downplayed nowadays. You _have_ to descend a little bit to do so,
>>
>> How tall is the wake?
>
> Good point. Still, using the calculator at:
>
> http://www.csgnetwork.com/aircraftturninfocalc.html
>
> It's going to take about 30 seconds to fly a 360 steep turn at
> 100kts. My wake _should_ descend about 150' during that time (300
> fpm). I can't imagine a C172 wake being tall enough to stay in my
> way unless something else is ocurring (me descending, or the wake
> staying up).
>
> Would love to hear a decent explanation. Kev
>

I am certainly no expert on the subject, but I think most of the data on
wake turbulence comes from studies held at or very near the ground.
Certainly not all, because I recall an old FAA film on landing in wake
turbulence using a 182 to fly into the wake at altitude. But IIRC it was
part of an awareness film on wake turbulence on approach, just demonstrated
at altitude for safe demonstration of its actual effects.

Based on the numbers I recall, they did indeed teach that the wake from a
landing heavy would NORMALLY travel both down and away from the aircraft a 5
kts or so. But they were also quick to mention that a simple 5 kt or so
crosswind componet could leave the vortex in the middle of the runway for
quite some time.

The problem with trying to use this information at altitude is that you
don't have the ground to help stablize the vertical movement of the vortex.
And every pilot knows the air at altitude is very seldom static, especailly
in warm weather. As someone else mentioned, the vortex that started as a
very small column at the wing tip, can grow very large by the time you
complete a 360 turn at even 60 degrees of bank.

The point is, you are dealing with far to many variables to expect absolute
answers your question or even your own in flight results. Wake turbulence is
really only a problem at altitude if you don't avoid the flight path of
heaver aircraft, and understanding it's presence on take off and landing,
because it is much easier to intercept their flight path around runways.

[Maxwell]

"Mxsmanic" > wrote in message
...
> writes:
>
>> Upon what do you base the assumption your wake should decend 150'?
>
> All wakes descend; they have to, otherwise the aircraft could not stay
> aloft.
> They move at a few knots, which still amounts to some 500 fpm.
>
>> I have never heard of any study of the wake properties of GA aircraft
>> and the wake of a C172 is very different than the wake of a 747 ...
>
> Since you haven't heard of any study of the wake properties of GA
> aircraft,
> you cannot possibly know whether the wake of a C172 is "very different"
> from
> that of a 747 or not. Oops!
>
> In fact, the general principle is the same for all aircraft wakes. They
> always move downward gently. You cannot catch them in a turn unless you
> move
> downward, too. If you are in rising air, the wake might remain stationary
> relative to the ground, but then your aircraft would be rising, so you'd
> still
> have to descend relative to the surrounding air in order to catch your
> wake.
> And smoothly rising air isn't that common, although it's not that rare.
>

You butt head. You clearly don't even understand the simplist properties of
an aircraft vortex.

[Maxwell]

"Mxsmanic" > wrote in message
...
> Jose writes:
>
>> How tall is the wake?
>
> The downwash is at least equal in height to the total wingspan of the
> aircraft. Downwash is a large mass of air moving slowly. Still, you
> should
> not be hitting your own wake in a 360-degree turn unless you are
> descending to
> catch it. Oddly enough, if you are descending, the wake moves more slowly
> (because you are generating less lift).
>

Priceless bucko!!!!!

It sounds to me like you are experiencing some serious wake tubulence in the
airspace between your ears.

[Maxwell]

"Mxsmanic" > wrote in message
...
> mike regish writes:
>
>> On a bumpy day you wouldn't be able to tell the wake from the overall
>> turbulence.
>
> I agree.
>
>> On an otherwise smooth day you can.
>
> Probably--if you actually hit it.
>
>> It can be done, Tony.
>
> Not without descending. The wake _must_ descend. This means that you
> cannot
> catch it unless you descend, also. If you can explain how this rule can
> be
> broken, I'm listening.
>

Total bull****. You haven't a clue.

[Maxwell]

"Mxsmanic" > wrote in message
...
> writes:
>
>> Just because you have never experienced it and can't understand it
>> from your many hours of playing the Flight Simulator game doesn't
>> mean it doesn't exist.
>
> My study of aerodynamics thus far indicates that it is impossible, unless
> you
> descend to catch your descending wake. Wakes _always_ descend. It's a
> consequence of the mechanism that produces the lift that sustains the
> aircraft, and it's unavoidable. Every source that I have consulted points
> this out, without exception. Your mere assertion to the contrary is
> completely unpersuasive in comparison.
>
>> It just means you don't know a whole lot about real flying or what
>> happens in a real airplane.
>
> No, it means that I look at the facts, and I don't depend on the legends.
>
>> Have you ever done a short field take off in your Flight Simulator
>> Cessna with the springy gear and had the mains vibrate for a few
>> seconds shaking the airplane?
>
> I don't fly the Cessna, and I fly only at airports with hard, smooth
> runways
> that won't bounce the aircraft around.
>

No your haven't. You have never flown anything but your desk, and regardless
of your medications, it never left the floor.

[rq3]

Mxsmanic wrote:
> Not without descending. The wake _must_ descend. This means that you cannot
> catch it unless you descend, also. If you can explain how this rule can be
> broken, I'm listening.
>
Then listen hard. The wake consists of more than just the downwash you
are fixated on. If you have ever seen a sky-writer at work, you would
know, even without setting foot in a real aircraft, that it is possible
to return to the same parcel of air and pass through the smoke you had
left previously.
On a calm day, no descending or climbing is required.
Your problem is your fixation on your assumptions, and then insisting
that physical reality must be wrong when your limited assumptions don't
square with that reality, a true sign of immaturity and a basic
inability to assimilate the information that your own senses provide.
Anthony, I'm actually beginning to feel sorry for you. I believe that
you have real, diagnosable mental issues.

Rip

[JB]

On Apr 16, 10:45 am, Mxsmanic > wrote:
> Kev writes:
> > On a warm clear day (which is when I've hit my own
> > wake), I betcha that the wake is being held upward a tiny bit by the
> > heat from the ground.
>
> Then you must be descending through the rising column of air.
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

You are such an idiot! Probably every GA pilot-in-training with a
C152/172 or something similar has experienced hitting their own wake
when performing their first steep turn with an instructor. I know I
did. I routinely show non-flying friends this phenomenon when I take
them flying.

But go ahead...keep arguing with experience that you don't have.

--Jeff

[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> Jose writes:

> > I can. 150 feet is not tall at all for a wake.

> It's extremely tall for a small aircraft. The wake would probably be about 50
> feet high.

> > Remember, the air around the wake is also being dragged by the wake vortex.

> But at very slow speed. Even the downwash itself is moving slowly, only a few
> knots. Any of the winds that one often encounters at altitude would be enough
> to rapidly disperse it.

You have no idea of the altitudes or winds aloft at which most people
practice maneuvers in real airplanes.

Wind by itself will not "disperse" anything, it will just move it.

It takes turbulant air to disperse things in the air.

--
Jim Pennino

Remove .spam.sux to reply.

[Maxwell]

"rq3" > wrote in message
et...
> Anthony, I'm actually beginning to feel sorry for you. I believe that you
> have real, diagnosable mental issues.

I can assure you he does. He has proven it beyond a reasoanble doubt on far
too many occasions.

[rq3]

Mxsmanic wrote:
> My study of aerodynamics thus far indicates that it is impossible, unless you
> descend to catch your descending wake. Wakes _always_ descend.
> SNIP
Still fixated on the idea that the downwash is the only component of
wake, huh, Anthony?

> No, it means that I look at the facts, and I don't depend on the legends.
>SNIP
No, it means that you look at SOME of the facts, and then draw incorrect
conclusions from limited information.

Rip

[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> writes:

> > Upon what do you base the assumption your wake should decend 150'?

> All wakes descend; they have to, otherwise the aircraft could not stay aloft.
> They move at a few knots, which still amounts to some 500 fpm.

No, they don't, and no it doesn't.

You have nothing to back up what you say.

> > I have never heard of any study of the wake properties of GA aircraft
> > and the wake of a C172 is very different than the wake of a 747 ...

> Since you haven't heard of any study of the wake properties of GA aircraft,
> you cannot possibly know whether the wake of a C172 is "very different" from
> that of a 747 or not. Oops!

If I fly through the wake of a 747 I risk things like suddenly finding
myself inverted or structural failure.

If I fly through the wake of a C172 I feel a slight bump.

Oops!

> In fact, the general principle is the same for all aircraft wakes. They
> always move downward gently. You cannot catch them in a turn unless you move
> downward, too. If you are in rising air, the wake might remain stationary
> relative to the ground, but then your aircraft would be rising, so you'd still
> have to descend relative to the surrounding air in order to catch your wake.
> And smoothly rising air isn't that common, although it's not that rare.

Is this knowledge based upon your many years of playing the Flight
Simulator game?

Just because playing a Microsoft game gives you no basis for understanding
something that many thousands of people have experienced does not mean
that it doesn't exist.

--
Jim Pennino

Remove .spam.sux to reply.

[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> mike regish writes:

> > On a bumpy day you wouldn't be able to tell the wake from the overall
> > turbulence.

> I agree.

> > On an otherwise smooth day you can.

> Probably--if you actually hit it.

> > It can be done, Tony.

> Not without descending. The wake _must_ descend. This means that you cannot
> catch it unless you descend, also. If you can explain how this rule can be
> broken, I'm listening.

What rule?

All we have is the babblings of a Microsoft game player.

--
Jim Pennino

Remove .spam.sux to reply.

[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> writes:

> > Just because you have never experienced it and can't understand it
> > from your many hours of playing the Flight Simulator game doesn't
> > mean it doesn't exist.

> My study of aerodynamics thus far indicates that it is impossible, unless you
> descend to catch your descending wake. Wakes _always_ descend. It's a
> consequence of the mechanism that produces the lift that sustains the
> aircraft, and it's unavoidable. Every source that I have consulted points
> this out, without exception. Your mere assertion to the contrary is
> completely unpersuasive in comparison.

Then obviously your study of aerodynamics thus far is incomplete as
it can not explain what really happens in real life to real pilots.

Theory is confirmed or invalidated by experiment.

Your theories are invalidated by years of experiments, i.e. actual
pilots flying actual airplanes.

> > It just means you don't know a whole lot about real flying or what
> > happens in a real airplane.

> No, it means that I look at the facts, and I don't depend on the legends.

So now your are reduced to the semantic arguement that the experiences
of thousands of pilots for many, many years are but a legend?

> > Have you ever done a short field take off in your Flight Simulator
> > Cessna with the springy gear and had the mains vibrate for a few
> > seconds shaking the airplane?

> I don't fly the Cessna, and I fly only at airports with hard, smooth runways
> that won't bounce the aircraft around.

Yet another statement that only goes to show a Microsoft flying game
is not an accurate representation of what happens in real airplanes.

The surface of the runway has nothing to do with the effect mentioned
and a whole lot with the maneuver performed.

--
Jim Pennino

Remove .spam.sux to reply.

[Mxsmanic]

writes:

> You have no idea of the altitudes or winds aloft at which most people
> practice maneuvers in real airplanes.

Neither does anyone else. You don't know until you get there.

> Wind by itself will not "disperse" anything, it will just move it.

Winds interacting with each other will disperse lots of things.

> It takes turbulant air to disperse things in the air.

See above.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Mxsmanic]

writes:

> You have nothing to back up what you say.

I have NASA, the FAA, a couple of engineering schools at universities, and
other sources that back up what I say. I'm simply standing on the shoulders
of giants.

> Is this knowledge based upon your many years of playing the Flight
> Simulator game?

No, it is based upon years of studying aviation.

Flight Simulator allows me to put theory into practice, mainly.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Maxwell]

"Mxsmanic" > wrote in message
...
> writes:
>
>> You have nothing to back up what you say.
>
> I have NASA, the FAA, a couple of engineering schools at universities, and
> other sources that back up what I say. I'm simply standing on the
> shoulders
> of giants.
>
>> Is this knowledge based upon your many years of playing the Flight
>> Simulator game?
>
> No, it is based upon years of studying aviation.
>
> Flight Simulator allows me to put theory into practice, mainly.
>

You forgot to deduct for your learning disability and selective
comprehension skills.

[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> writes:

> > You have no idea of the altitudes or winds aloft at which most people
> > practice maneuvers in real airplanes.

> Neither does anyone else. You don't know until you get there.

Another essentially true, but worthless statement that serves no
purpose other than to play semantic word games.

Most practice maneuvers are done in a small altitude box for reasons
that Microsoft flying games do not simulate.

> > Wind by itself will not "disperse" anything, it will just move it.

> Winds interacting with each other will disperse lots of things.

There is no such thing as "winds" at a particular point in the sky,
there is only the wind.

> > It takes turbulant air to disperse things in the air.

> See above.

Turbulant air is caused by differences in wind over an area.


--
Jim Pennino

Remove .spam.sux to reply.

[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> writes:

> > You have nothing to back up what you say.

> I have NASA, the FAA, a couple of engineering schools at universities, and
> other sources that back up what I say. I'm simply standing on the shoulders
> of giants.

> > Is this knowledge based upon your many years of playing the Flight
> > Simulator game?

> No, it is based upon years of studying aviation.

> Flight Simulator allows me to put theory into practice, mainly.

Babbling nonsense.

--
Jim Pennino

Remove .spam.sux to reply.

[Mxsmanic]

Maxwell writes:

> As someone else mentioned, the vortex that started as a
> very small column at the wing tip, can grow very large by the time you
> complete a 360 turn at even 60 degrees of bank.

And it will be so weak that you won't feel it even if you run into it, which
you won't do unless you descend.

--
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[Mxsmanic]

JB writes:

> You are such an idiot! Probably every GA pilot-in-training with a
> C152/172 or something similar has experienced hitting their own wake
> when performing their first steep turn with an instructor.

Steep turns tend to be descending turns.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Mxsmanic]

Maxwell writes:

> Total bull****.

No, I've already heard that. I was hoping for a scientific explanation.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Maxwell]

"Mxsmanic" > wrote in message
...
> Maxwell writes:
>
>> As someone else mentioned, the vortex that started as a
>> very small column at the wing tip, can grow very large by the time you
>> complete a 360 turn at even 60 degrees of bank.
>
> And it will be so weak that you won't feel it even if you run into it,
> which
> you won't do unless you descend.
>

Thank you.

I just love it when you prove your ignorance and inexperience in a single
statement.

The really is thoughtful. Save the band width.

[Maxwell]

"Mxsmanic" > wrote in message
...
> JB writes:
>
>> You are such an idiot! Probably every GA pilot-in-training with a
>> C152/172 or something similar has experienced hitting their own wake
>> when performing their first steep turn with an instructor.
>
> Steep turns tend to be descending turns.
>

Trim Luke! Trim. You forgot the Jedi Trim.

[Maxwell]

"Mxsmanic" > wrote in message
...
> Maxwell writes:
>
>> Total bull****.
>
> No, I've already heard that. I was hoping for a scientific explanation.
>

Gee?? I wonder why?

[Mxsmanic]

rq3 writes:

> The wake consists of more than just the downwash you
> are fixated on. If you have ever seen a sky-writer at work, you would
> know, even without setting foot in a real aircraft, that it is possible
> to return to the same parcel of air and pass through the smoke you had
> left previously.

I never questioned that.

> On a calm day, no descending or climbing is required.

How do you know? What skywriting have you done?

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Mxsmanic]

rq3 writes:

> Still fixated on the idea that the downwash is the only component of
> wake, huh, Anthony?

I've never been fixated on such a notion. All of the wake behind an aircraft
descends, including the downwash.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> JB writes:

> > You are such an idiot! Probably every GA pilot-in-training with a
> > C152/172 or something similar has experienced hitting their own wake
> > when performing their first steep turn with an instructor.

> Steep turns tend to be descending turns.

Yeah, when playing Microsoft flying games; not for real pilots.

--
Jim Pennino

Remove .spam.sux to reply.

[Rip]

Mxsmanic wrote:
> rq3 writes:
>
>
>>The wake consists of more than just the downwash you
>>are fixated on. If you have ever seen a sky-writer at work, you would
>>know, even without setting foot in a real aircraft, that it is possible
>>to return to the same parcel of air and pass through the smoke you had
>>left previously.
>
>
> I never questioned that.
>
>
>>On a calm day, no descending or climbing is required.
>
>
> How do you know? What skywriting have you done?
>
About 200 hours aerobatics with smoke. What skywriting have YOU done?

Rip

[Rip]

Mxsmanic wrote:

> rq3 writes:
>
>
>>Still fixated on the idea that the downwash is the only component of
>>wake, huh, Anthony?
>
>
> I've never been fixated on such a notion. All of the wake behind an aircraft
> descends, including the downwash.
>
Please provide a reliable reference for that staement.

Rip

[Mxsmanic]

Maxwell writes:

> Trim Luke! Trim.

Add power.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Maxwell]

"Mxsmanic" > wrote in message
...
> Maxwell writes:
>
>> Trim Luke! Trim.
>
> Add power.
>

That's right Luke, add the power of the trim!!!!! Now your are getting
it!!!!!!!!!!!!!!

[mike regish]

What is the vertical component of the vector if you have the wake traveling
outward perpindicular to the wings? It will be 150' from the original path,
but at an angle to vertical.

mike

"Kev" > wrote in message
ups.com...
> On Apr 16, 9:41 am, Jose > wrote:
>> > I seem to recall recent magazine (web?) articles where the idea that
>> > you can hit your own wake while actually holding altitude, should be
>> > downplayed nowadays. You _have_ to descend a little bit to do so,
>>
>> How tall is the wake?
>
> Good point. Still, using the calculator at:
>
> http://www.csgnetwork.com/aircraftturninfocalc.html
>
> It's going to take about 30 seconds to fly a 360 steep turn at
> 100kts. My wake _should_ descend about 150' during that time (300
> fpm). I can't imagine a C172 wake being tall enough to stay in my
> way unless something else is ocurring (me descending, or the wake
> staying up).
>
> Would love to hear a decent explanation. Kev
>

[mike regish]

And maintaining you altitude above the ground via altimeter...

mike

"Mxsmanic" > wrote in message
...
>
> Then you must be descending through the rising column of air.
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

[Mxsmanic]

Maxwell writes:

> That's right Luke, add the power of the trim!!!!!

No, power instead of trim. You need more lift.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Mxsmanic]

Rip writes:

> About 200 hours aerobatics with smoke.

No skywriting?

> What skywriting have YOU done?

None.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Mxsmanic]

Rip writes:

> Please provide a reliable reference for that staement.

Every reference I can find mentions it.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[mike regish]

We have. Rising air. It happens all the time over the plowed cornfields I
fly over. The plane doesn't also rise with the air because we are
maintaining out altitude above the ground.

mike
"Mxsmanic" > wrote in message
...
>
> If you can explain how this rule can be
> broken, I'm listening.
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

[Rip]

Mxsmanic wrote:
> Rip writes:
>
>
>>About 200 hours aerobatics with smoke.
>
>
> No skywriting?
>
>
>>What skywriting have YOU done?
>
>
> None.
>
But you've sure blown a lot of smoke!
By the way, where's the reliable reference for the
"all wake descends" statement you made earlier?

Rip

[Rip]

Mxsmanic wrote:

> Rip writes:
>
>
>>Please provide a reliable reference for that staement.
>
>
> Every reference I can find mentions it.
>
Quote one.

Rip

[Thomas Borchert]

Mxsmanic,

> Flight Simulator allows me to put theory into practice, mainly.
>

Another priceless gem! What practice???

--
Thomas Borchert (EDDH)

[Thomas Borchert]

Mxsmanic,

> Steep turns tend to be descending turns.
>

Why does anyone bother arguing with this idiot? Please!

--
Thomas Borchert (EDDH)

[Rip]

Thomas Borchert wrote:
> Mxsmanic,
>
>
>>Steep turns tend to be descending turns.
>>
>
>
> Why does anyone bother arguing with this idiot? Please!
>
No, no, Thomas. He's right, but you have to force fit your mental
processes into a replica of his very limited ones. As everyone else but
Anthony knows, steep turns do indeed TEND to be descending turns, unless
specific action is taken to remain at a constant altitude. The fact that
any competent pilot can complete a 360 within 10 feet of the initial
altitude seems to escape him.

Unfortunately, Anthony cannot make the simple leap from assuming his
vaunted "research" is correct, even though it provides the wrong answer,
to asking himself, "Let me assume that the empirical experiments
conducted by hundreds of thousands of real world pilots provide
hypothetical proof that an aircraft, completing a 360 degree turn at a
constant altitude, can indeed run through its own wake. What new
assumptions must I make to make this so, and how can I verify those
assumptions?"

That's how science works. Anthony thinks it's done by referring to
un-quotable armchair research about very restricted, generally incorrect
assumptions on his part. Then, when he is wrong, he becomes repetitive,
pedantic, and frustrated.

Oh well. The entire thread has forced me to ask myself just what the
wake behind an aircraft looks like. Like every other pilot, I know you
can intercept your own wake during a constant altitude turn, but it
would be neat to be able to SEE all of the air masses at work. Modern
computation isn't up to the task of separating out all of the variables
involved. Which is why a simulator, any simulator, is a very limited
substitute for reality. Poor Anthony.

Rip

[Mxsmanic]

mike regish writes:

> We have. Rising air. It happens all the time over the plowed cornfields I
> fly over. The plane doesn't also rise with the air because we are
> maintaining out altitude above the ground.

Therefore you are descending into your wake. QED.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Jim Stewart]

Mxsmanic wrote:
> JB writes:
>
>
>>You are such an idiot! Probably every GA pilot-in-training with a
>>C152/172 or something similar has experienced hitting their own wake
>>when performing their first steep turn with an instructor.
>
>
> Steep turns tend to be descending turns.

Anthony, this is exactly why you antagonize so many
people in the aviation forums.

*Every* pilot (at least in the US) learns steep turns
in the context of the FAA's practical test standard.
That's a steep turn while holding your altitude +/- 100
feet. In reality, we train to hold the altitude constant
during the turn, so that involves modulated back pressure
on the stick and probably more throttle.

http://www.faa.gov/education_research/testing/airmen/test_standards/pilot/media/FAA-S-8081-14A.pdf

PDF page 48.

Your original response would possibly meaningful on
a simulator forum. On a flying forum, you should
understand your lack of background and context before
posting presumptuous statements.

[flynrider via AviationKB.com]

Maxwell wrote:
>> Anthony, I'm actually beginning to feel sorry for you. I believe that you
>> have real, diagnosable mental issues.
>
>I can assure you he does. He has proven it beyond a reasoanble doubt on far
>too many occasions.

And yet there are still over 50 posts in this thread encouraging his
behavior.

Good job guys. He owns you.

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

--
Message posted via AviationKB.com
http://www.aviationkb.com/Uwe/Forums.aspx/aviation/200704/1

[RomeoMike]

I don't know if he "cannot" or will not or just wants to get under
everyone's skin. What you say in this post is correct. But why do people
keep responding and arguing ad nauseum with someone who can't or won't
get it? What's the dynamic? I doubt that there has ever been a pilot who
has not flown into his own wake in a constant altitude 360. So this is
not a topic that one pilot needs to prove to another pilot with a
different opinion.

Rip wrote:

>
> Unfortunately, Anthony cannot make the simple leap from assuming his
> vaunted "research" is correct, even though it provides the wrong answer,
> to asking himself, "Let me assume that the empirical experiments
> conducted by hundreds of thousands of real world pilots provide
> hypothetical proof that an aircraft, completing a 360 degree turn at a
> constant altitude, can indeed run through its own wake. What new
> assumptions must I make to make this so, and how can I verify those
> assumptions?"
>

[Gary[_2_]]

On Apr 16, 3:06 pm, Mxsmanic > wrote:
> mike regish writes:
> > We have. Rising air. It happens all the time over the plowed cornfields I
> > fly over. The plane doesn't also rise with the air because we are
> > maintaining out altitude above the ground.
>
> Therefore you are descending into your wake. QED.

What part of "maintaining our altitude" sounds like "descending" to
you?

[Rip]

Mxsmanic wrote:
> mike regish writes:
>
>
>>We have. Rising air. It happens all the time over the plowed cornfields I
>>fly over. The plane doesn't also rise with the air because we are
>>maintaining out altitude above the ground.
>
>
> Therefore you are descending into your wake. QED.
>
Excellent, Anthony! This is almost a real breakthrough for you! We'll
work on your semantic errors in a moment, but the mere fact that you've
just admitted here, in public, that an aircraft at constant altitude can
run through it's own wake is tremendous progress on your part. Good boy!
See what happens when you take my suggestions to re-examine your
erroneous assumptions?

So let's work on those semantics, shall we? News flash! Earth to
Anthony! An aircraft at a constant altitude is not descending! We'll all
wait while you digest that. No, no, take your time. We all know it will
require several days of intense concentration and pointless posting for
it to sink into your limited neural capacity.

Seriously, I'm deeply gratified that you picked up a new skill today; to
wit, the ability to assimilate information which goes against your
preconceived notions, and actually synthesize a situation that would
allow such a thing to be so. I know it's hard for you, but the majority
of the human race does it almost effortlessly. Don't worry, it gets
easier with practice. Anything else we can help you with?

Rip

[Kev]

On Apr 16, 10:45 am, Mxsmanic > wrote:
> Kev writes:
> > On a warm clear day (which is when I've hit my own
> > wake), I betcha that the wake is being held upward a tiny bit by the
> > heat from the ground.
>
> Then you must be descending through the rising column of air.

Not necessarily. Visualize that I begin my turn over a field where
the air is rising slightly. The rest of my turn is over another area
(lake perhaps) where the air is static. I am not descending through
the rising column yet I manage to hit my own wake because it was held
in place.

Kev

[Mxsmanic]

Jim Stewart writes:

> *Every* pilot (at least in the US) learns steep turns
> in the context of the FAA's practical test standard.
> That's a steep turn while holding your altitude +/- 100
> feet.

If you meet your wake, you're descending.

--
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[Mxsmanic]

Gary writes:

> What part of "maintaining our altitude" sounds like "descending" to
> you?

The part that is combined with rising air.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Jim Stewart]

Mxsmanic wrote:

> Jim Stewart writes:
>
>
>>*Every* pilot (at least in the US) learns steep turns
>>in the context of the FAA's practical test standard.
>>That's a steep turn while holding your altitude +/- 100
>>feet.
>
>
> If you meet your wake, you're descending.
>

My post had nothing to do with descending.
It had to do with why you're treated like
a fool on aviation forums. You should address
that issue rather than getting fixated on
steep turns and descending....

[Snowbird]

"Rip" wrote ...
>
> Oh well. The entire thread has forced me to ask myself just what the wake
> behind an aircraft looks like. Like every other pilot, I know you can
> intercept your own wake during a constant altitude turn, but it would be
> neat to be able to SEE all of the air masses at work.

Thanks for your smoke insights ;-)
There are some great photos depicting the tip vortices here:
http://www.airliners.net/open.file/1091105/M/
http://www.airliners.net/open.file/1008033/M/

Here are some real masterpieces :

http://www.airtoair.net/gallery/gallery-vortices.htm


I guess Mxmanic uses the FAA AIM as his main source in his "research".
Section 7.3.1 is about wake turbulence. A couple of interesting quotes from
that section, that Mx has not seen fit to share with us:

a) "Flight tests have shown that the vortices from larger (transport
category) aircraft sink at a rate of several hundred feet per minute,
slowing their descent and diminishing in strength with time and distance
behind the generating aircraft."

Note the explicit reference to large aircraft. In fact, it seems all actual
wake turbulence safety studies have involved large aircraft, i.e. B707 and
larger. This is in fact quite natural, as there was no real safety issue
before the large jetliners appeared.
b) "Test data have shown that vortices can rise with the air mass in which
they are embedded."

There you are, official proof to the statements of several of our
contributors.

c) "The greatest vortex strength occurs when the generating aircraft is
HEAVY, CLEAN, and SLOW."

In contrast, a light aircraft doing a 360 is usually LIGHT, CLEAN and
(relatively speaking) FAST. Very different conditions, especially regarding
two major sources of wake: the AoA of the wing (which affects the tip
vortices) and the power setting (which affects the propwash strength).

The interesting study question here, for the light airplane case, would be
the relation between the tip vortices (which presumably sink, as for large
aircraft) and the propwash (which is basically horizontal). I think glider
pilots can testify that the propwash is the dominant one, at least close
behind the tug airplane - any soarers out there who can comment?

But realistically, as the wake behind a light aircraft is no real safety
hazard, there is no compelling reason to study this case. So unless someone
can produce a reference, let's rely on the observational data from countless
pilots.

[Rip]

Beautiful, Snowbird. I've seen the effect in reality, but those are some
magnificent photos!

Rip

[Kev]

On Apr 16, 10:22 am, Jose > wrote:
> > My wake _should_ descend about 150' during that time (300
> > fpm). I can't imagine a C172 wake being tall enough to stay in my
> > way...
>
> I can. 150 feet is not tall at all for a wake. Remember, the air
> around the wake is also being dragged by the wake vortex.

Hmm. We're going to have to define a wake, methinks. I can't find
anything about body wakes, for example. Do they give much of a
bump? Glider pilots, are you listening?

On the other hand, wingtip vortices are a well-researched topic, and
if a Boeing 727's is only 9' in radius, it would be hard to imagine a
vortex being more than 5 feet in radius for a C172, if that much.
Even if larger, and sinking very slowly, it should still be 50-150'
below the aircraft if the other parameters (altitude, wind) are
static.

Regards, Kev

[Tom L.]

On 16 Apr 2007 06:37:13 -0700, "Kev" > wrote:

>On Apr 14, 4:27 pm, "george" > wrote:
>> I always maintained altitude and rate of turn in steep turns with the
>> end result being hitting my own slipstream.
>
>As have we all on nice days, and students like to brag about it. Yet
>Mx is correct, in theory we should not be able to do this.
>
>I seem to recall recent magazine (web?) articles where the idea that
>you can hit your own wake while actually holding altitude, should be
>downplayed nowadays. You _have_ to descend a little bit to do so,
>which means that, while you might be within the +/- 100' test
>scenario, you are NOT holding the same exact altitude.
>
>Hmm. Or else it means that the wake doesn't necessarily descend as
>we're taught. On a warm clear day (which is when I've hit my own
>wake), I betcha that the wake is being held upward a tiny bit by the
>heat from the ground.
>
>Cheers, Kev
>
>

The big question is "why does the wake turbulence descend?"
Is the air volume inside the vortices denser than surrounding air?
Probably not. So the descent is probably not due to gravitational
force.

I am no expert on fluid dynamics and have no access to texts that
answer the question (if there are any), but figure 7-3-5 in AIM is
interesting - it shows a wake sinking at several hundred fpm
immediately after an aircraft, but than stabilizing at several hunderd
feet below the flightpath, i.e. no further sink. This might indicate
that the sink is due to wing downwash.

If that is the case, than
1. Wake turbulence in steep turns will not move just downward, but
down and out, that is: opposite lift.
2. The speed at which it moves will depend on downwash - it's speed,
intensity, strength (?) I don't know which term would be appropriate
here. Whatever it is, it might be much smaller for GA aircraft than
for large aircraft.

It would be interesting to do the following flight test:
On a nice day (meaning: perfectly still air) fly turns at different
bank angles and speeds and note when you do and don't experience the
bump at the end of the turn. Do this in different aircraft - low/high
wing, small/large/...

Does anyone know whether big aircraft experience the bump at the
conclusion of their steep 360s?

- Tom

[Rip]

RomeoMike wrote:

> I don't know if he "cannot" or will not or just wants to get under
> everyone's skin. What you say in this post is correct. But why do people
> keep responding and arguing ad nauseum with someone who can't or won't
> get it? What's the dynamic? I doubt that there has ever been a pilot who
> has not flown into his own wake in a constant altitude 360. So this is
> not a topic that one pilot needs to prove to another pilot with a
> different opinion.

The only dynamic is between the pilots on the group, certainly not with
MX. But, as I mentioned, the thread forced me to ask myself just what it
was I am "running over" when I hit my own wake turbulence. Does it
matter? Probably not, but this enquiring mind wants to know. I still
don't have the answer. Rising wingtip vortices in warm air? Prop wash?
"Burbles" from the passage of non-lifting surfaces like the fuselage?

We all know it happens. I'm just one of those weirdos that wants to know
WHY it happens. As a result of this thread, it appears that nobody
knows. It's an unstudied regime of flight. I find THAT interesting!
Perhaps it could lead to some super-terrific drag reduction technique,
like surfing on your own wake? After all, that's why geese fly in "V"
formation.

Rip

[Rip]

Tom L. wrote:


> Does anyone know whether big aircraft experience the bump at the
> conclusion of their steep 360s?


I don't know, but I'm going to find out! I can envision an aircraft with
light wing loading, like a Cessna for instance, compressing the air
locally as it creates lift. After passage of the wing, the lift created
downwash would rebound upward, kind of like skipping a stone on the
water. The end result is that the downwash stays at a constant altitude,
or sinks MUCH more slowly than theory would indicate. Not a good
analogy, but you've got me thinking!

Rip

[Maxwell]

"Mxsmanic" > wrote in message
...
> Maxwell writes:
>
>> That's right Luke, add the power of the trim!!!!!
>
> No, power instead of trim. You need more lift.
>
Right Luke!!! Right!!!!! The power to add trim.

[Kev]

On Apr 16, 11:15 am, "Maxwell" > wrote:
> "Kev" > wrote in message
> > It's going to take about 30 seconds to fly a 360 steep turn at
> > 100kts. My wake _should_ descend about 150' during that time (300
> > fpm). I can't imagine a C172 wake being tall enough to stay in my
> > way unless something else is ocurring (me descending, or the wake
> > staying up).
>
> I am certainly no expert on the subject, but I think most of the data on
> wake turbulence comes from studies held at or very near the ground.

My searches on the web show the opposite... or at least that there's
studies both at altitude and near the ground. For examples:

http://www.nasa.gov/centers/dryden/about/Organizations/Technology/Facts/TF-2004-14-DFRC.html

"NASA research has shown that as large aircraft move through the air,
trailing vortices tend to remain spaced less than a wingspan apart
while sinking at a rate of several hundred feet per minute. Over time,
the sink rate will slow and their strength will taper off. Research
has shown, however, that vortices can also rise during conditions of
ambient thermal lifting."

"Aircraft Accident Reconstruction and Litigation" By M. P. Papadakis,
Barnes Warnock MacCormick, states that vortices descend 5-10 fps
(30-600 fpm).

> Based on the numbers I recall, they did indeed teach that the wake from a
> landing heavy would NORMALLY travel both down and away from the aircraft a 5
> kts or so. But they were also quick to mention that a simple 5 kt or so
> crosswind componet could leave the vortex in the middle of the runway for
> quite some time.

Yes, we were all taught that part.

> The problem with trying to use this information at altitude is that you
> don't have the ground to help stablize the vertical movement of the vortex.

Here is information taken at altitude: Vortices are 14-36 feet in
diameter, approx the wingspan apart, and sink 160 - 1100 fpm.

http://www.airpower.maxwell.af.mil/airchronicles/aureview/1971/jul-aug/carten.html

I just think it's an interesting question, because we've all had it
happen, but no one here can give a definitive reason for it (beyond
"yo stupid of course it does" which is pretty lame even for the usual
Mx bashers ;-)

I think I've convinced myself that since I don't always hit my wake on
a perfect steep turn, and because it mostly seems to happen over areas
of rising air, that the explanation is simple. Unless someone can
post better research.

Thanks, Kev

[Maxwell]

"Kev" > wrote in message
oups.com...
>
> I think I've convinced myself that since I don't always hit my wake on
> a perfect steep turn, and because it mostly seems to happen over areas
> of rising air, that the explanation is simple. Unless someone can
> post better research.
>

Great, now what do you intend to do with the imformation?

[Snowbird]

"Rip" wrote ...
>
> We all know it happens. I'm just one of those weirdos that wants to know
> WHY it happens. As a result of this thread, it appears that nobody knows.
> It's an unstudied regime of flight. I find THAT interesting!

Me too ;-)

I actually tried yesterday... with poor results for the connect ;(

But the GPS track provided an explanation. It showed my 360s were not proper
full circles, i.e. at the exit I crossed the previous flight path at an
angle (more than 45 degrees in fact) instead of actually flying in the same
circle track as the entry of the 360. Not so easy to explain, but the result
was that the airplane was only in the potential wake area for a fraction of
a second. I guess you need to fly so that the flightpath is well aligned
with the original circle, in order to catch the wake.

Back to the theory:
I read some interesting basic aerodynamics of drag. According to the book,
at low speeds the induced drag (which is a side effect of the lift force) is
larger than the parasite drag (caused by frontal area, landing gear etc).
But at higher speeds (above 70 mph in the example case, a light plane)
parasite drag becomes the dominant drag component. Now, the induced drag is
creating the tip vortices, which presumably descend, but parasite drag has
no vertical component, so in theory it should stay in place. So according to
this, the higher the airplane's relative speed, the slower the wake will
descend (if at all).

I look forward to the results of the group's experiments ;-)

[Dan Luke]

"Snowbird" wrote:
> I actually tried yesterday... with poor results for the connect ;(
>
> But the GPS track provided an explanation. It showed my 360s were not
> proper full circles, i.e. at the exit I crossed the previous flight path at
> an angle (more than 45 degrees in fact) instead of actually flying in the
> same circle track as the entry of the 360.

That's probably because there was wind aloft. GPS shows your track over the
ground, not your track WRT the moving air mass.

In perfectly calm conditions, GPS track would show a circle if you flew one
properly.

--
Dan
C-172RG at BFM

[[email protected]]

In rec.aviation.piloting Kev > wrote:
> On Apr 16, 11:15 am, "Maxwell" > wrote:
> > "Kev" > wrote in message
> > > It's going to take about 30 seconds to fly a 360 steep turn at
> > > 100kts. My wake _should_ descend about 150' during that time (300
> > > fpm). I can't imagine a C172 wake being tall enough to stay in my
> > > way unless something else is ocurring (me descending, or the wake
> > > staying up).
> >
> > I am certainly no expert on the subject, but I think most of the data on
> > wake turbulence comes from studies held at or very near the ground.

> My searches on the web show the opposite... or at least that there's
> studies both at altitude and near the ground. For examples:

> http://www.nasa.gov/centers/dryden/about/Organizations/Technology/Facts/TF-2004-14-DFRC.html




|||||
> "NASA research has shown that as large aircraft move through the air,
|||||
> trailing vortices tend to remain spaced less than a wingspan apart
> while sinking at a rate of several hundred feet per minute. Over time,
> the sink rate will slow and their strength will taper off. Research
> has shown, however, that vortices can also rise during conditions of
> ambient thermal lifting."

> "Aircraft Accident Reconstruction and Litigation" By M. P. Papadakis,
> Barnes Warnock MacCormick, states that vortices descend 5-10 fps
> (30-600 fpm).

Where's the data for C172 sized aircraft?

People are assuming numbers for a specific type of aircraft are
applicable to very different aircraft.

I see no justification for this.

<snip rest>

--
Jim Pennino

Remove .spam.sux to reply.

[swag]

On Apr 16, 1:39 pm, Mxsmanic > wrote:
> Jim Stewart writes:
> > *Every* pilot (at least in the US) learns steep turns
> > in the context of the FAA's practical test standard.
> > That's a steep turn while holding your altitude +/- 100
> > feet.
>
> If you meet your wake, you're descending.
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

I have sent the following question to an aerospace engineer at the
Rand corporation for his response...I'll keep you posted:
There is a thread on one of the aviation usenet groups that got me to
thinking...
In training, it it routinely common for a pilot to practice steeps
turns, and when you reach the roll out of a 360 degree turn with a
bank angle of 45-60 degrees, you will feel a hard bump, which most
instructors say is due to going through your own wake. One of the
commentators is arguing that this can't happen due to the fact that
wake turbulence descends. But it is a clearly easily demonstrated
effect. Is it our own wake? Or are we creating a vertical vortex
with the maneuver of a steep turn? (rather than the wake of wingtip
vortices). Is the data on wake turbulence behavior applicable to a
shrply turning aircraft?

[Mxsmanic]

Snowbird writes:

> Now, the induced drag is
> creating the tip vortices, which presumably descend, but parasite drag has
> no vertical component, so in theory it should stay in place. So according to
> this, the higher the airplane's relative speed, the slower the wake will
> descend (if at all).

The entire air mass behind the aircraft is descending. The downwash descends,
and air from above moves down to replace it. While parasitic drag is not
associated with lift and thus has no vertical component of its own, any
turbulence it creates will still drift downward with the downwash, although
perhaps less quickly than the downwash itself, depending on where the
turbulence leaves the aircraft.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Mxsmanic]

Snowbird writes:

> I guess Mxmanic uses the FAA AIM as his main source in his "research".

That is only one of many sources. They all say the same thing.

> a) "Flight tests have shown that the vortices from larger (transport
> category) aircraft sink at a rate of several hundred feet per minute,
> slowing their descent and diminishing in strength with time and distance
> behind the generating aircraft."
>
> Note the explicit reference to large aircraft. In fact, it seems all actual
> wake turbulence safety studies have involved large aircraft, i.e. B707 and
> larger. This is in fact quite natural, as there was no real safety issue
> before the large jetliners appeared.

The wakes of smaller aircraft descend as well.

> b) "Test data have shown that vortices can rise with the air mass in which
> they are embedded."
>
> There you are, official proof to the statements of several of our
> contributors.

Including myself.

> c) "The greatest vortex strength occurs when the generating aircraft is
> HEAVY, CLEAN, and SLOW."

Yes. Although the downwash itself should be strongest when the aircraft is
dirty and slow. The reason clean and slow produces stronger _vortices_ is
that it only produces one pair, whereas flaps and other control surfaces can
produce multiple vortices of smaller size that tend to interfere with each
other and reduce overall turbulence.

> In contrast, a light aircraft doing a 360 is usually LIGHT, CLEAN and
> (relatively speaking) FAST. Very different conditions, especially regarding
> two major sources of wake: the AoA of the wing (which affects the tip
> vortices) and the power setting (which affects the propwash strength).

Which makes it all the more difficult to understand how a pilot could feel his
own wake in a level 360-degree turn.

> The interesting study question here, for the light airplane case, would be
> the relation between the tip vortices (which presumably sink, as for large
> aircraft) and the propwash (which is basically horizontal). I think glider
> pilots can testify that the propwash is the dominant one, at least close
> behind the tug airplane - any soarers out there who can comment?

You're neglecting the downwash, which is present in all aircraft. Downwash
tends to pull all turbulence behind the aircraft down with it.

> But realistically, as the wake behind a light aircraft is no real safety
> hazard, there is no compelling reason to study this case. So unless someone
> can produce a reference, let's rely on the observational data from countless
> pilots.

And ignore the factual data from countless resources? What makes pilots more
reliable? Most pilots barely understand how lift works to begin with.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Mxsmanic]

Kev writes:

> Not necessarily. Visualize that I begin my turn over a field where
> the air is rising slightly. The rest of my turn is over another area
> (lake perhaps) where the air is static. I am not descending through
> the rising column yet I manage to hit my own wake because it was held
> in place.

Since these would be very unusual circumstances, they cannot substantiate the
claim that pilots routinely meet their own wakes in 360-degree turns.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Mxsmanic]

Tom L. writes:

> The big question is "why does the wake turbulence descend?"

Because it's the downwash from the aircraft's wings. Aircraft stay in the air
by pushing air downward. As the wings pass through still air, they twist the
air downward as they pass. The force required to do this engenders an equal
and opposite force that raises the wings--lift, in other words.

No downwash = no lift.

Turbulence is mostly from wingtip vortices. The vortices exist because air is
twisting over to the top of the wings from the bottom. The vortices are
necessary in order to accommodate the swath of downwash behind the aircraft,
which is descending in relation to the still air on either side of the
aircraft's path.

> Is the air volume inside the vortices denser than surrounding air?

Density has nothing to do with it. The air has been pushed downward by the
wings.

> Probably not. So the descent is probably not due to gravitational
> force.

No, it's not gravity. The air descends because the wings pushed it down.

> I am no expert on fluid dynamics and have no access to texts that
> answer the question (if there are any), but figure 7-3-5 in AIM is
> interesting - it shows a wake sinking at several hundred fpm
> immediately after an aircraft, but than stabilizing at several hunderd
> feet below the flightpath, i.e. no further sink. This might indicate
> that the sink is due to wing downwash.

It is.

> If that is the case, than
> 1. Wake turbulence in steep turns will not move just downward, but
> down and out, that is: opposite lift.

Yes.

> 2. The speed at which it moves will depend on downwash - it's speed,
> intensity, strength (?) I don't know which term would be appropriate
> here. Whatever it is, it might be much smaller for GA aircraft than
> for large aircraft.

The product of air mass times downwash acceleration has to be the same as the
product of aircraft weight times gravity. So a larger and heavier aircraft
produces a larger downwash, albeit not necessarily a faster one.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Mxsmanic]

Rip writes:

> I don't know, but I'm going to find out! I can envision an aircraft with
> light wing loading, like a Cessna for instance, compressing the air
> locally as it creates lift. After passage of the wing, the lift created
> downwash would rebound upward, kind of like skipping a stone on the
> water.

Virtually no compression occurs at the speeds of a Cessna. Compression is
only an issue at high speeds. At low speeds, air behaves very much like an
imcompressible fluid.

> The end result is that the downwash stays at a constant altitude,
> or sinks MUCH more slowly than theory would indicate.

The downwash does not stay at a constant altitude. It sinks. It has to,
otherwise the aircraft couldn't stay in the air.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Kev]

On Apr 16, 3:59 pm, Tom L. > wrote:
> The big question is "why does the wake turbulence descend?"
> Is the air volume inside the vortices denser than surrounding air?

Whoa, good guess. I just read a reference that said the vortex
descends until it meets air of its own density and then dissipates.
It was surprising to read. Let me see if I can find that site
again...

Kev

[Mxsmanic]

writes:

> Where's the data for C172 sized aircraft?

Small aircraft work the same way, since they have wings that work the same
way.

> People are assuming numbers for a specific type of aircraft are
> applicable to very different aircraft.

These facts are applicable to all fixed-wing aircraft.

> I see no justification for this.

You're assuming a difference where no evidence for a difference exists.

--
Transpose mxsmanic and gmail to reach me by e-mail.

[Kev]

On Apr 16, 3:47 pm, "Snowbird" > wrote:
> I guess Mxmanic uses the FAA AIM as his main source in his "research".
> Section 7.3.1 is about wake turbulence. A couple of interesting quotes from
> that section, that Mx has not seen fit to share with us:

Heh. Many of his responders seem to have done even less "research".
Instead they substitute insults for information, hoping they'll look
smarter than him. They don't seem to realize that it just makes them
look dumber.

> c) "The greatest vortex strength occurs when the generating aircraft is
> HEAVY, CLEAN, and SLOW."
>
> In contrast, a light aircraft doing a 360 is usually LIGHT, CLEAN and
> (relatively speaking) FAST. Very different conditions, especially regarding
> two major sources of wake: the AoA of the wing (which affects the tip
> vortices) and the power setting (which affects the propwash strength).

Of course, LIGHT does not mean "light aircraft". Some 152s are
vortex HEAVY in the case of big instructors and students ;-)

For vortex strength, the term HEAVY is used in a relative manner. A
small plane that is lightly loaded will create less vortex strength
than the same small plane that is heavily loaded, because the actual
AOA is larger in the latter case.

The actual AOA is the key for (HEAVY) more load, (CLEAN) less flaps
and (SLOW) less speed. It's greater in all those cases.

Auugh. Four year old calling me. Later..
Best, Kev

[Maxwell]

"Mxsmanic" > wrote in message
...
> writes:
>
>> Where's the data for C172 sized aircraft?
>
> Small aircraft work the same way, since they have wings that work the same
> way.
>
>> People are assuming numbers for a specific type of aircraft are
>> applicable to very different aircraft.
>
> These facts are applicable to all fixed-wing aircraft.
>
>> I see no justification for this.
>
> You're assuming a difference where no evidence for a difference exists.
>


Priceless!!! You are dead wrong again.

[Tom L.]

On Mon, 16 Apr 2007 23:33:54 +0200, Mxsmanic >
wrote:

>Rip writes:
>
>> I don't know, but I'm going to find out! I can envision an aircraft with
>> light wing loading, like a Cessna for instance, compressing the air
>> locally as it creates lift. After passage of the wing, the lift created
>> downwash would rebound upward, kind of like skipping a stone on the
>> water.
>
>Virtually no compression occurs at the speeds of a Cessna. Compression is
>only an issue at high speeds. At low speeds, air behaves very much like an
>imcompressible fluid.
>
>> The end result is that the downwash stays at a constant altitude,
>> or sinks MUCH more slowly than theory would indicate.
>
>The downwash does not stay at a constant altitude. It sinks. It has to,
>otherwise the aircraft couldn't stay in the air.

It doesn't have to continue to sink forever. It can stabilize its
position at some point.

To explain the encounter with one's own wake turbulence we need some
quantification for a particular aircraft/bank/speed:
- radii of the vortices
- "sink" rate ("sink" meaning movement away from the flight path, not
necessarily downward)
- final "sink" distance

E.g. if the vertex radius is 15 feet and sink rate 20 fpm, we hit the
wake after a 30 second turn.
If the radius is 15 feet, sink rate 100 fpm, and final distance 10
feet, we still hit it.
And so on.

So what are the right numbers?
We know from experience that a right combination of those numbers
exists in reality.

- Tom

[DJW]

On Apr 16, 11:00 am, Mxsmanic > wrote:
> writes:
> > Just because you have never experienced it and can't understand it
> > from your many hours of playing the Flight Simulator game doesn't
> > mean it doesn't exist.
>
> My study of aerodynamics thus far indicates that it is impossible, unless you
> descend to catch your descending wake. Wakes _always_ descend. It's a
> consequence of the mechanism that produces the lift that sustains the
> aircraft, and it's unavoidable. Every source that I have consulted points
> this out, without exception. Your mere assertion to the contrary is
> completely unpersuasive in comparison.
>

My only comment on this subject - I'm not going to bother arguing
about it, as 1) according to the aerodynamics, it definitely IS
possible to fly through your own wake turbulence in steep turns, and
2) like most people who have actually done steep turns in a real plane
in calm air, I've done it.

Tip vortices (the major part of wake turbulence) extend outward and a
fair distance UPWARD from the wingtip. As well, since the plane is
banked in a turn in the described situation, the vortices descend at a
much slower rate than they would for S&L flight. A simple search will
reveal several NASA and other studies with graphics and photos
depicting an aircraft flying through smoke and the resulting tip
vortices. One of the photos that is in a few studies shows a small Ag
plane, with the upward spiral of the tip vortices reaching 2-3 times
the height of the aircraft, and outward from the wing by half a
wingspan, near the ground. As ground effect decreases the vortices,
at altitude they can be larger.


> > It just means you don't know a whole lot about real flying or what
> > happens in a real airplane.
>
> No, it means that I look at the facts, and I don't depend on the legends.
>
Then you haven't found all of the facts.

> > Have you ever done a short field take off in your Flight Simulator
> > Cessna with the springy gear and had the mains vibrate for a few
> > seconds shaking the airplane?
>
> I don't fly the Cessna, and I fly only at airports with hard, smooth runways
> that won't bounce the aircraft around.
>
Planes bounce just fine on hard, smooth runways - ask any pre-solo
student.

> --
> Transpose mxsmanic and gmail to reach me by e-mail.

[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> writes:

> > Where's the data for C172 sized aircraft?

> Small aircraft work the same way, since they have wings that work the same
> way.

> > People are assuming numbers for a specific type of aircraft are
> > applicable to very different aircraft.

> These facts are applicable to all fixed-wing aircraft.

> > I see no justification for this.

> You're assuming a difference where no evidence for a difference exists.

Yes, you are quite correct; there is no differece between a 747 and
a C172 in the Microsoft Flight Simulator game.


--
Jim Pennino

Remove .spam.sux to reply.

[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> Kev writes:

> > Not necessarily. Visualize that I begin my turn over a field where
> > the air is rising slightly. The rest of my turn is over another area
> > (lake perhaps) where the air is static. I am not descending through
> > the rising column yet I manage to hit my own wake because it was held
> > in place.

> Since these would be very unusual circumstances, they cannot substantiate the
> claim that pilots routinely meet their own wakes in 360-degree turns.

Yes, these would be very unusual circumstances in the Microsoft
Flight Simulator game.


--
Jim Pennino

Remove .spam.sux to reply.

[Snowbird]

"Kev" wrote ...
>
> Of course, LIGHT does not mean "light aircraft". Some 152s are
> vortex HEAVY in the case of big instructors and students ;-)
>
I see your point ;-)

However, I've never seen a condensation trail behind a C152 wingtip. Not
that it necessarily means anything.

But you made me think about air viscosity, i.e. friction that dissipates
turbulence. One might argue that a C152 flies in relatively "thicker" air
than a B757 and thus a vortex or downwash might not propagate away from the
flightpath as easily. How far from a bumblebee can its downwash be felt?

Just rambling ... ;-)

[Mxsmanic]

Tom L. writes:

> It doesn't have to continue to sink forever. It can stabilize its
> position at some point.

It will sink indefinitely unless some other force acts to stop it. In theory,
it will sink until it reaches the ground.

In other words, in theory, an aircraft lays down a swath of downwash from the
time it leaves ground effect on the runway until the time it lands in ground
effect again. The entire swatch theoretically touches down on the ground
eventually.

> E.g. if the vertex radius is 15 feet and sink rate 20 fpm, we hit the
> wake after a 30 second turn.

Twenty feet per minute is too slow. The downwash will move at at least a few
knots, and even three knots is 300 fpm.

--
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[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> Rip writes:

> > I don't know, but I'm going to find out! I can envision an aircraft with
> > light wing loading, like a Cessna for instance, compressing the air
> > locally as it creates lift. After passage of the wing, the lift created
> > downwash would rebound upward, kind of like skipping a stone on the
> > water.

> Virtually no compression occurs at the speeds of a Cessna. Compression is
> only an issue at high speeds. At low speeds, air behaves very much like an
> imcompressible fluid.

Wave your hand through the air. Did it feel like an imcompressible fluid?

--
Jim Pennino

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[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> Tom L. writes:

> > It doesn't have to continue to sink forever. It can stabilize its
> > position at some point.

> It will sink indefinitely unless some other force acts to stop it. In theory,
> it will sink until it reaches the ground.

Do you get your physics from Microsoft Physics Simulator.

<snip remaining babble>

--
Jim Pennino

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[Mxsmanic]

writes:

> Do you get your physics from Microsoft Physics Simulator.

I got this from aviation sources.

--
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[Mxsmanic]

writes:

> Wave your hand through the air. Did it feel like an imcompressible fluid?

Yes. Does your Cessna provide equivalent airspeed?

--
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[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> writes:

> > Wave your hand through the air. Did it feel like an imcompressible fluid?

> Yes. Does your Cessna provide equivalent airspeed?

Did you use Microsoft Air Simulator to do this?

OK, now wave your hand through a real fluid, I'd suggest water.

Did it feel the same as waving your hand through air?

What Cessna?

--
Jim Pennino

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[mike regish]

Wrong.

mike

"Mxsmanic" > wrote in message
...
>
> And it will be so weak that you won't feel it even if you run into it,
> which
> you won't do unless you descend.
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

[mike regish]

Not if properly done.

mike

"Mxsmanic" > wrote in message
...
> JB writes:
>
>> You are such an idiot! Probably every GA pilot-in-training with a
>> C152/172 or something similar has experienced hitting their own wake
>> when performing their first steep turn with an instructor.
>
> Steep turns tend to be descending turns.
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

[mike regish]

You really are dense.

The airmass is rising relative to the ground and carrying the wake with it
(minus its sink) so they can cancel out. We (pilots) are maintaining our
altitude relative to the ground-descending relative to the airmass, but not
relative to the ground.

mike

"Mxsmanic" > wrote in message
...
> mike regish writes:
>
>> We have. Rising air. It happens all the time over the plowed cornfields I
>> fly over. The plane doesn't also rise with the air because we are
>> maintaining out altitude above the ground.
>
> Therefore you are descending into your wake. QED.
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

[mike regish]

Not always.

mike

"Mxsmanic" > wrote in message
...
> Jim Stewart writes:
>
>> *Every* pilot (at least in the US) learns steep turns
>> in the context of the FAA's practical test standard.
>> That's a steep turn while holding your altitude +/- 100
>> feet.
>
> If you meet your wake, you're descending.
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

[Mxsmanic]

writes:

> Did you use Microsoft Air Simulator to do this?

You haven't answered my question.

> OK, now wave your hand through a real fluid, I'd suggest water.
>
> Did it feel the same as waving your hand through air?

If you look in books on aerodynamics, you'll find that air is effectively an
incompressible fluid at low speeds, such as those encountered in small
aircraft. It isn't until you get to the transonic range that compression
starts to be an issue, and the rules change substantially at and beyond the
speed of sound.

--
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[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> writes:

> > Did you use Microsoft Air Simulator to do this?

> You haven't answered my question.

What question?

> > OK, now wave your hand through a real fluid, I'd suggest water.
> >
> > Did it feel the same as waving your hand through air?

> If you look in books on aerodynamics, you'll find that air is effectively an
> incompressible fluid at low speeds, such as those encountered in small
> aircraft. It isn't until you get to the transonic range that compression
> starts to be an issue, and the rules change substantially at and beyond the
> speed of sound.

Have you ever looked in a book?

--
Jim Pennino

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[Kev]

On Apr 16, 3:59 pm, Tom L. > wrote:
> The big question is "why does the wake turbulence descend?"
> Is the air volume inside the vortices denser than surrounding air?

Found it, Tom. Ref:

http://www.airpower.maxwell.af.mil/airchronicles/aureview/1971/jul-aug/carten.html

"Cruise altitude vortices usually level off at about 1000 feet below
the altitude of the aircraft as their density comes into equilibrium
with that of the surrounding air. Decay processes then take over. "

Regards, Kev

[Tim[_4_]]

"Mxsmanic" > wrote...
> Rip writes:
>
>> Please provide a reliable reference for that staement.
>
> Every reference I can find mentions it.

Interestingly, MSFS will simulate this very effect in a C172 or a Baron in a
level 360 degree turn.

I wonder why the software would imitate something that cannot happen in real
life?

BDS

[Jose]

> On the other hand, wingtip vortices are a well-researched topic, and
> if a Boeing 727's is only 9' in radius,

cite? I remember seeing pictures of wingtip vortices (of fair sized
aircraft) and they looked like they were more than 18 feet across.

Jose
--
Get high on gasoline: fly an airplane.
for Email, make the obvious change in the address.

[Maxwell]

"Kev" > wrote in message
ups.com...
> On Apr 16, 3:59 pm, Tom L. > wrote:
>> The big question is "why does the wake turbulence descend?"
>> Is the air volume inside the vortices denser than surrounding air?
>
> Found it, Tom. Ref:
>
> http://www.airpower.maxwell.af.mil/airchronicles/aureview/1971/jul-aug/carten.html
>
> "Cruise altitude vortices usually level off at about 1000 feet below
> the altitude of the aircraft as their density comes into equilibrium
> with that of the surrounding air. Decay processes then take over. "
>

Don't underestimate the value of the words "usually" and "about" in that
sentence. You are still trying to absolutely describe something that is very
dynamic.

[Mxsmanic]

Tim writes:

> Interestingly, MSFS will simulate this very effect in a C172 or a Baron in a
> level 360 degree turn.

Will it? It doesn't simulate wake turbulence generally, why would it simulate
this?

> I wonder why the software would imitate something that cannot happen in real
> life?

So do I.

--
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[Kev]

On Apr 17, 12:02 am, Jose > wrote:
> > On the other hand, wingtip vortices are a well-researched topic, and
> > if a Boeing 727's is only 9' in radius,
>
> cite? I remember seeing pictures of wingtip vortices (of fair sized
> aircraft) and they looked like they were more than 18 feet across.

Sorry was not cited here, but in other posts. To repeat:

http://www.airpower.maxwell.af.mil/airchronicles/aureview/1971/jul-aug/carten.html

Yes, I would've thought much bigger too, but then they wouldn't be as
much a threat so far behind an aircraft if they expanded quickly in
diameter. Apparently if flaps or spoilers aren't used, the danger
area behind a 747, for example, extends many more miles than we're
usually taught:

http://www.nasa.gov/centers/dryden/about/Organizations/Technology/Facts/TF-2004-14-DFRC.html

Still haven't found much on really light aircraft ( < 26,000 lbs), but
the concept should be the same, albeit at a much smaller amplitude.
There are equations for calculating the vortex, but they seem hard to
get at on the web.

Of interest: wingtip vortices were first formally written about in
1907 (!), and the use of vertical fins to cut down the drag on wings,
dates over a decade before that.

Regards, Kev

[swag]

On Apr 13, 6:23 pm, Mxsmanic > wrote:
> Little Endian writes:
> > In the sim it makes no sense to avoid wake turbulence because you will
> > never know if you succeeded, its an exercise in futility.
>
> Real life is like that, too. You only know when you fail to avoid wake
> turbulence, not when you succeed.
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

OK--I consulted an aerospace engineer at the rand corporation and he
said:
"The vortex does tend to drop, but pretty slowly. Even if it does,
couldn't you be feeling the vortex off the upper (in a left bank,
the
right) wing?"

[DR]

Tom L. wrote:
> On Mon, 16 Apr 2007 23:33:54 +0200, Mxsmanic >
> wrote:
>
>> Rip writes:
>>
>>> I don't know, but I'm going to find out! I can envision an aircraft with
>>> light wing loading, like a Cessna for instance, compressing the air
>>> locally as it creates lift. After passage of the wing, the lift created
>>> downwash would rebound upward, kind of like skipping a stone on the
>>> water.
>> Virtually no compression occurs at the speeds of a Cessna. Compression is
>> only an issue at high speeds. At low speeds, air behaves very much like an
>> imcompressible fluid.
>>
>>> The end result is that the downwash stays at a constant altitude,
>>> or sinks MUCH more slowly than theory would indicate.
>> The downwash does not stay at a constant altitude. It sinks. It has to,
>> otherwise the aircraft couldn't stay in the air.
>
> It doesn't have to continue to sink forever. It can stabilize its
> position at some point.
>
> To explain the encounter with one's own wake turbulence we need some
> quantification for a particular aircraft/bank/speed:
> - radii of the vortices
> - "sink" rate ("sink" meaning movement away from the flight path, not
> necessarily downward)
> - final "sink" distance
>
> E.g. if the vertex radius is 15 feet and sink rate 20 fpm, we hit the
> wake after a 30 second turn.
> If the radius is 15 feet, sink rate 100 fpm, and final distance 10
> feet, we still hit it.
> And so on.
>

Hi Tom,

The key may be to understand that while the center of vortex system
moves down, air outside the vortex _has_ to move up. (By imparting
energy to the vortex (and thereby sustaining it) lift is generated). If
you like, the "top" of the vortex can stay at the same level (or even
move up) while the center of the vortex moves down as the vortex grows
with distance behind the wing. At low angles of attack the vortex center
moves slowly down and at high angles it moves down faster (and is more
intense). I'll predict that as you fly in a circle you start to create
yet _another_ vortex with a radius equal to that of the turn. This
vortex is centered on your path of flight and will become closed if you
contine the 360 degree turn. At that point, as I see it, you may
experience the angle of bank wanting to increase -have you ever felt
that? Now add in (1) parasitic drag from the airframe (2) propwash and
(3) tail vortex and you are even more likely to encounter your own
"turbulence".

Comments?

Cheers

[Thomas Borchert]

Rip,

> As everyone else but
> Anthony knows, steep turns do indeed TEND to be descending turns, unless
> specific action is taken to remain at a constant altitude.
>

Can't follow you there. That's as useful a statement as "airplanes tend to
be stationary objects..."

--
Thomas Borchert (EDDH)

[[email protected]]

On Apr 16, 11:33 pm, Mxsmanic > wrote:
>
> Virtually no compression occurs at the speeds of a Cessna. Compression is
> only an issue at high speeds. At low speeds, air behaves very much like an
> imcompressible fluid.
>

Air does not behave very much like an imcompressible fluid at low air
speeds. Not even close.
Under some conditions, low air speeds is one of them, air can be
treated like it is an imcompressible fluid.
And that is only to simplify airflow calculations.

-Kees.

[Tim[_4_]]

"Mxsmanic" > wrote...
> Tim writes:
>
>> Interestingly, MSFS will simulate this very effect in a C172 or a Baron
>> in a
>> level 360 degree turn.
>
> Will it? It doesn't simulate wake turbulence generally, why would it
> simulate
> this?

Yes, it will. Try it - if you're good enough you will see it happen. If
not, you have to practice your 360s.

>> I wonder why the software would imitate something that cannot happen in
>> real
>> life?
>
> So do I.

An interesting dilemma - either MSFS is bogus or Mx is wrong... has hell
frozen over?

BDS

[[email protected]]

In rec.aviation.piloting wrote:
> On Apr 16, 11:33 pm, Mxsmanic > wrote:
> >
> > Virtually no compression occurs at the speeds of a Cessna. Compression is
> > only an issue at high speeds. At low speeds, air behaves very much like an
> > imcompressible fluid.
> >

> Air does not behave very much like an imcompressible fluid at low air
> speeds. Not even close.
> Under some conditions, low air speeds is one of them, air can be
> treated like it is an imcompressible fluid.
> And that is only to simplify airflow calculations.

> -Kees.

Quite so.

Mxsmanic has once again has taken a tiny snippet of information that
is only applicable within a narrow set of constraints and arm waved
it into a truism under all conditions.

If air truely behaved like an incompressilble fluid at low air speeds,
it would be difficult, if not impossible, to breathe while jogging.

--
Jim Pennino

Remove .spam.sux to reply.

[Mxsmanic]

Thomas Borchert writes:

> Can't follow you there. That's as useful a statement as "airplanes tend to
> be stationary objects..."

In a turn, a portion of the lift produced by the wings must be used to
accelerate the aircraft laterally, and this portion of the lift is no longer
available to maintain the aircraft's altitude. Thus, without any adjustment
of pitch or power to compensate, any turn will result in a loss of altitude.

--
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[Mxsmanic]

writes:

> Air does not behave very much like an imcompressible fluid at low air
> speeds. Not even close.

That's not what the engineers say.

> Under some conditions, low air speeds is one of them, air can be
> treated like it is an imcompressible fluid.

The difference between TAS and EAS is only about 13% even at Mach 1. Since
small aircraft come nowhere near to Mach 1, for all practical purposes air is
incompressible for most calculations.

Obviously air, being a gas, can be compressed, but taking that into account at
low speeds greatly complicates the calculations, and the final result isn't
significantly different.

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[Mxsmanic]

Tim writes:

> An interesting dilemma - either MSFS is bogus or Mx is wrong... has hell
> frozen over?

Many of the MSFS developers are pilots, for better or for worse.

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[Mxsmanic]

writes:

> If air truely behaved like an incompressilble fluid at low air speeds,
> it would be difficult, if not impossible, to breathe while jogging.

It's possible to breathe water, which is indeed incompressible for all
practical purposes.

--
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[Kev]

On Apr 17, 11:06 am, Mxsmanic > wrote:
> In a turn, a portion of the lift produced by the wings must be used to
> accelerate the aircraft laterally, and this portion of the lift is no longer
> available to maintain the aircraft's altitude. Thus, without any adjustment
> of pitch or power to compensate, any turn will result in a loss of altitude.

All pilots know this and assume that a "turn" includes compensation,
unless they specifically say "descending" or "climbing".

So when you keep saying "a turn will always descend", you just confuse
your readers... especially the ones who don't follow threads closely.
You're in a pilot newsgroup, which means the prevailing terminology is
that of pilots, not necessarily engineers, civilians, or whomever.

Kev

[rq3]

Just spoke to a friend with 26,000 hours. He confirmed that DC-8 and 707
heavies certainly do get a bump as they fly through their own wake
during a 360 degree constant altitude turn. He also said that some
Category D simulators include the effect in their motion repertoire.

Rip


Kev wrote:
> On Apr 16, 10:22 am, Jose > wrote:
>>> My wake _should_ descend about 150' during that time (300
>>> fpm). I can't imagine a C172 wake being tall enough to stay in my
>>> way...
>> I can. 150 feet is not tall at all for a wake. Remember, the air
>> around the wake is also being dragged by the wake vortex.
>
> Hmm. We're going to have to define a wake, methinks. I can't find
> anything about body wakes, for example. Do they give much of a
> bump? Glider pilots, are you listening?
>
> On the other hand, wingtip vortices are a well-researched topic, and
> if a Boeing 727's is only 9' in radius, it would be hard to imagine a
> vortex being more than 5 feet in radius for a C172, if that much.
> Even if larger, and sinking very slowly, it should still be 50-150'
> below the aircraft if the other parameters (altitude, wind) are
> static.
>
> Regards, Kev
>

[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> Thomas Borchert writes:

> > Can't follow you there. That's as useful a statement as "airplanes tend to
> > be stationary objects..."

> In a turn, a portion of the lift produced by the wings must be used to
> accelerate the aircraft laterally, and this portion of the lift is no longer
> available to maintain the aircraft's altitude. Thus, without any adjustment
> of pitch or power to compensate, any turn will result in a loss of altitude.

Yet another true but worthless statement.

One of the first things real pilots are taught in real training in
real airplanes is how to maintain a constant altitude in a turn.

Ergo any real turns by real airplanes will be constant altitude
unless the PILOT has a reason to do otherwise.

Since most 360 turns are done as practice to establish and maintain
the skill, most 360 turns will be at a constant altitude +/- 100 feet.

--
Jim Pennino

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[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> writes:

> > If air truely behaved like an incompressilble fluid at low air speeds,
> > it would be difficult, if not impossible, to breathe while jogging.

> It's possible to breathe water, which is indeed incompressible for all
> practical purposes.

And yet another factoid that is only applicable under a very
contrained set of circumstances you are trying to arm wave into
a generallity to prove yourself correct.

And no, it is not possible to breathe water, you can only breathe
gases, if you want to be pendantically, semantically correct.


--
Jim Pennino

Remove .spam.sux to reply.

[rq3]

Yes, they do. I just asked a friend with 26,000 hours. He confirmed that
DC-8's and 707's do get a bump as they cross their own wake in a 360
degree constant altitude turn. He also said that some Category D
simulators include this effect in their motion repertoire.

Rip

Tom L. wrote:
> On 16 Apr 2007 06:37:13 -0700, "Kev" > wrote:
>
>> On Apr 14, 4:27 pm, "george" > wrote:
>>> I always maintained altitude and rate of turn in steep turns with the
>>> end result being hitting my own slipstream.
>> As have we all on nice days, and students like to brag about it. Yet
>> Mx is correct, in theory we should not be able to do this.
>>
>> I seem to recall recent magazine (web?) articles where the idea that
>> you can hit your own wake while actually holding altitude, should be
>> downplayed nowadays. You _have_ to descend a little bit to do so,
>> which means that, while you might be within the +/- 100' test
>> scenario, you are NOT holding the same exact altitude.
>>
>> Hmm. Or else it means that the wake doesn't necessarily descend as
>> we're taught. On a warm clear day (which is when I've hit my own
>> wake), I betcha that the wake is being held upward a tiny bit by the
>> heat from the ground.
>>
>> Cheers, Kev
>>
>>
>
> The big question is "why does the wake turbulence descend?"
> Is the air volume inside the vortices denser than surrounding air?
> Probably not. So the descent is probably not due to gravitational
> force.
>
> I am no expert on fluid dynamics and have no access to texts that
> answer the question (if there are any), but figure 7-3-5 in AIM is
> interesting - it shows a wake sinking at several hundred fpm
> immediately after an aircraft, but than stabilizing at several hunderd
> feet below the flightpath, i.e. no further sink. This might indicate
> that the sink is due to wing downwash.
>
> If that is the case, than
> 1. Wake turbulence in steep turns will not move just downward, but
> down and out, that is: opposite lift.
> 2. The speed at which it moves will depend on downwash - it's speed,
> intensity, strength (?) I don't know which term would be appropriate
> here. Whatever it is, it might be much smaller for GA aircraft than
> for large aircraft.
>
> It would be interesting to do the following flight test:
> On a nice day (meaning: perfectly still air) fly turns at different
> bank angles and speeds and note when you do and don't experience the
> bump at the end of the turn. Do this in different aircraft - low/high
> wing, small/large/...
>
> Does anyone know whether big aircraft experience the bump at the
> conclusion of their steep 360s?
>
> - Tom

[rq3]

Anthony, you've got the issue of compressibility precisely backwards. No
surprise.

Rip

Mxsmanic wrote:
> Rip writes:
>
>> I don't know, but I'm going to find out! I can envision an aircraft with
>> light wing loading, like a Cessna for instance, compressing the air
>> locally as it creates lift. After passage of the wing, the lift created
>> downwash would rebound upward, kind of like skipping a stone on the
>> water.
>
> Virtually no compression occurs at the speeds of a Cessna. Compression is
> only an issue at high speeds. At low speeds, air behaves very much like an
> imcompressible fluid.
>
>> The end result is that the downwash stays at a constant altitude,
>> or sinks MUCH more slowly than theory would indicate.
>
> The downwash does not stay at a constant altitude. It sinks. It has to,
> otherwise the aircraft couldn't stay in the air.
>

[rq3]

Anthony, my boy, your interpretation is incorrect. At Mach, the air has
compressed as much as it can, which is why it takes so much energy to
force a solid object through Mach. You have the concepts reversed in
your head.

Rip

Mxsmanic wrote:
> writes:
>
>> Did you use Microsoft Air Simulator to do this?
>
> You haven't answered my question.
>
>> OK, now wave your hand through a real fluid, I'd suggest water.
>>
>> Did it feel the same as waving your hand through air?
>
> If you look in books on aerodynamics, you'll find that air is effectively an
> incompressible fluid at low speeds, such as those encountered in small
> aircraft. It isn't until you get to the transonic range that compression
> starts to be an issue, and the rules change substantially at and beyond the
> speed of sound.
>

[rq3]

And it's darned difficult, just like the man said.
Hey, here's an idea, why don't you go get us some empirical data from
personal experimentation, and then get back to us with some actual
information!

Rip

Mxsmanic wrote:
> writes:
>
>> If air truely behaved like an incompressilble fluid at low air speeds,
>> it would be difficult, if not impossible, to breathe while jogging.
>
> It's possible to breathe water, which is indeed incompressible for all
> practical purposes.
>

[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> writes:

> > Air does not behave very much like an imcompressible fluid at low air
> > speeds. Not even close.

> That's not what the engineers say.

I am an engineer and have the degree to prove it and I totally agree
with him, so stuff it.

> > Under some conditions, low air speeds is one of them, air can be
> > treated like it is an imcompressible fluid.

> The difference between TAS and EAS is only about 13% even at Mach 1. Since
> small aircraft come nowhere near to Mach 1, for all practical purposes air is
> incompressible for most calculations.

Word salad that shows you don't get the concept.

At low airspeed, the equations for incompressible fluid flow are close
enough to what actually happens that they can be used for practical
calculations.

This does not mean that air "acts like an incompressible fluid" in any
way, shape, or form.

> Obviously air, being a gas, can be compressed, but taking that into account at
> low speeds greatly complicates the calculations, and the final result isn't
> significantly different.

Finally, the light comes on...

Well, gee-whiz, you backed into a place where you are finally correct.

Aren't you great?

--
Jim Pennino

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[Mxsmanic]

rq3 writes:

> Anthony, my boy, your interpretation is incorrect. At Mach, the air has
> compressed as much as it can, which is why it takes so much energy to
> force a solid object through Mach.

If it were compressed as much as it could be, it would be a liquid.

--
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[Mxsmanic]

writes:

> And no, it is not possible to breathe water, you can only breathe
> gases, if you want to be pendantically, semantically correct.

Water is breathable if there is enough oxygen in it, although the effect on
lung tissue over long periods of breathing a liquid has not been determined.
There are some therapeutic uses for techniques similar to this.

--
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[Mxsmanic]

writes:

> I am an engineer and have the degree to prove it and I totally agree
> with him, so stuff it.

I'm actually the King of England.

> Finally, the light comes on...

The light was always on, but it's hard to see through heavily tinted glasses.

--
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[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> rq3 writes:

> > Anthony, my boy, your interpretation is incorrect. At Mach, the air has
> > compressed as much as it can, which is why it takes so much energy to
> > force a solid object through Mach.

> If it were compressed as much as it could be, it would be a liquid.

Yet another (almost) true but worthless statement and semantic game.

You are really good at playing semantic games.

--
Jim Pennino

Remove .spam.sux to reply.

[[email protected]]

In rec.aviation.piloting Mxsmanic > wrote:
> writes:

> > And no, it is not possible to breathe water, you can only breathe
> > gases, if you want to be pendantically, semantically correct.

> Water is breathable if there is enough oxygen in it, although the effect on
> lung tissue over long periods of breathing a liquid has not been determined.
> There are some therapeutic uses for techniques similar to this.

Water is not breathable; only the oxygen (or other gases) contained in
it is.

You want to play semantic games?

--
Jim Pennino

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[swag]

On Apr 17, 9:10 am, Mxsmanic > wrote:
> Tim writes:
> > An interesting dilemma - either MSFS is bogus or Mx is wrong... has hell
> > frozen over?
>
> Many of the MSFS developers are pilots, for better or for worse.
>
> --
> Transpose mxsmanic and gmail to reach me by e-mail.

I believe that the explanation to why all pilots have experienced this
is that the vortices of a tight turn descend much more slowly than the
vortices generated in straight flight. All of the experimental data
that I can find on vortex descent rate has been done on planes in
straight flight (or in wind tunnels which is the same thing). All of
the reasons espoused in this thread for vortices to have any downward
velocity can be used to explain why numbers should change when the
wings aren't level.

The other factor that has been ignored is how fast a steep turn
executes. A 2g coordinated turn at 100 knots will complete in 19
seconds. (That's close to a 45 degree bank angle in most small
planes.) The formula to play with different loading factors and
speeds is:
rate of turn= omega = g*sqrt(n^2-1)/V

[rq3]

Wrong yet again! Wow, you're batting 1000! Most of the gases in air
require cooling in addition to compression to liquefy.

Rip

Mxsmanic wrote:
> rq3 writes:
>
>> Anthony, my boy, your interpretation is incorrect. At Mach, the air has
>> compressed as much as it can, which is why it takes so much energy to
>> force a solid object through Mach.
>
> If it were compressed as much as it could be, it would be a liquid.
>

[rq3]

Wrong again! Water is respirable at ambient pressures sufficiently high
to provide sufficient PO2 (that's partial pressure of oxygen, my boy).
Unfortunately, the problem is carbon dioxide solubility, which makes
water unusable. However, liquid respiration IS successfully done with
various fluorocarbon compounds.

Come now, Anthony. Try to get at least one fact straight.

Rip

Mxsmanic wrote:
> writes:
>
>> And no, it is not possible to breathe water, you can only breathe
>> gases, if you want to be pendantically, semantically correct.
>
> Water is breathable if there is enough oxygen in it, although the effect on
> lung tissue over long periods of breathing a liquid has not been determined.
> There are some therapeutic uses for techniques similar to this.
>

[rq3]

Wrong again, Anthony! There is no King of England.

Rip

Mxsmanic wrote:
> writes:
>
>> I am an engineer and have the degree to prove it and I totally agree
>> with him, so stuff it.
>
> I'm actually the King of England.
>
>> Finally, the light comes on...
>
> The light was always on, but it's hard to see through heavily tinted glasses.
>

[Judah]

Mxsmanic > wrote in
:

> That's not what the engineers say.

Name 3.

[Judah]

Mxsmanic > wrote in
:

> Many of the MSFS developers are pilots, for better or for worse.

Name 3