Backwash Causes Lift?

"Dudley Henriques" wrote in message
...
Tina wrote:
Then there's the Mx medical advice column, physics advice -- I'm
waiting for a unified field theory, or maybe a proposed standard of
care for depression.

I had a thought for what would be the longest thread ever in this
newsgroup -- "The collected corrections of Mx statements". Bertie
could be its editor, he has a deft and gentle way of pointing out
errors.



I love Bertie's personal rendition of Occam's Razor to Anthony's long
extended posts where he "explains" everything in intimate and minute
detail.

"Nope"!


--
Dudley Henriques

I'd like to see what his thoughts are on String Theory.
LOL.
Crash Lander

--
Straight and Level Down Under.
http://www.straightandleveldownunder.net/

Crash Lander wrote:
"Dudley Henriques" wrote in message
...
Tina wrote:
Then there's the Mx medical advice column, physics advice -- I'm
waiting for a unified field theory, or maybe a proposed standard of
care for depression.

I had a thought for what would be the longest thread ever in this
newsgroup -- "The collected corrections of Mx statements". Bertie
could be its editor, he has a deft and gentle way of pointing out
errors.


I love Bertie's personal rendition of Occam's Razor to Anthony's long
extended posts where he "explains" everything in intimate and minute
detail.

"Nope"!


--
Dudley Henriques

I'd like to see what his thoughts are on String Theory.
LOL.
Crash Lander


I'm sure he'd most likely say that twine was better :-))

--
Dudley Henriques

On Oct 3, 6:33 pm, "Morgans" wrote:
It goes something like this.

An airplane is about to takeoff on a runway, that is really a treadmill; a
very expensive treadmill.

The treadmill senses the airplane's speed, and matches the aircraft's
speed, with speed increases of its own.

Can the airplane takeoff? Why or why not?

I forgot one important qualifier of the treadmill's operation.

It goes in the opposite direction of the intended direction of travel for
the airplane.

Tricky question. I will take a stab at it.

You said "sense the airplanes speed". Relative to what?

Assuming no friction between wheels and treadmill, the prop of the
plane will cause the airplane to move in the wind. The speed
"sensing" of the airplane by the treadmill does not really make sense
and less you mean that the treadmill senses relative to the wind.

If the treadmill senses that the plane has a relative wind speed of
Vpw, and starts moving in the opposite direction, and the relative
speed of wind against treadwill were nil before all this started, then
the treadmill will only cause the wheels to turn twice as fast as they
would have if the treadmill had not been moving. In this case, the
speed of the plane relative to the treadmill will simply be twice the
speed of the plane relative to the win, in opposite direction, of
course. The plane will take off.

If you mean to imply that there is some way for the treadmill to sense
the speed of the plane relative to the treadmill, then adjust the
speed of treadmill accordingly, of course, that won't work, as it is a
circuitous proposition.

-Le Chaud Lapin-

"Bertie the Bunyip" ...
On 3 Oct, 13:27, "BDS" wrote:
"Mxsmanic" wrote

Le Chaud Lapin writes:

What is the definition of a stall anyway?

An abrupt loss of lift.

Son, for someone who continually chastises the pilots here for their
lack of
knowledge, you sure can come up with some doozies yourself!


Actually, it's correct, but only because he read it off wickepedia or
something.

Here's my take on it - a stall occurs at the angle of attack where the
coefficient of lift stops increasing with angle of attack and begins to
decrease. It continues to decrease beyond this point as angle of attack is
increased further. It is not necessarily an abrupt change - most lift
versus angle of attack curves that I've seen do not have a drastic (abrupt)
drop beyond the peak.

BDS

BDS wrote:
"Bertie the Bunyip" ...
On 3 Oct, 13:27, "BDS" wrote:
"Mxsmanic" wrote

Le Chaud Lapin writes:

What is the definition of a stall anyway?

An abrupt loss of lift.

Son, for someone who continually chastises the pilots here for their
lack of
knowledge, you sure can come up with some doozies yourself!


Actually, it's correct, but only because he read it off wickepedia or
something.

Here's my take on it - a stall occurs at the angle of attack where the
coefficient of lift stops increasing with angle of attack and begins to
decrease. It continues to decrease beyond this point as angle of attack is
increased further. It is not necessarily an abrupt change - most lift
versus angle of attack curves that I've seen do not have a drastic (abrupt)
drop beyond the peak.

Yes, sorry, you´re right and that´s more accurate. i mistakenly
assumed that you were adfvocating the buffet definition.


Bertie

Le Chaud Lapin wrote:
On Oct 3, 4:14 pm, Bertie the Bunyip
wrote:
Whoowh!
Zero point energy!


Surely, you must be joking. The exposition I wrote above is nothing
more than high school physics.

Where do you see me implying zero point energy?

I know my physics. Do you? There is no "zero point" energy.

Actually, there is. Not theory anymore, proven in a lab..

You´re proving to be quite the plaything.


Plain and simple:

If a person sucks on a straw, the reason the fluid rises has *NOTHING*
to do with Bernoull's principle. It has to do with the balance in
force being eliminated. In particular, the air in the straw is
removed, so the 14.4lbs/square in will lift the fluid in the straw.

This should be familiar to you, since you are a pilot. Where do you
think 29.92 Hg comes from? It comes from the height that a column of
mercury will rise in a complete rarefied tube in STP, which just
happens to be 29.92.

Both you and Mxmanic are wrong.


Maybe, but I can fly.



Bertie

Morgans wrote:
"Bertie the Bunyip" wrote

He's an idiot, what else does one need to know?

And yet so many can not resist posting replies to his posts, either with
corrections or witty zingers.

I'm starting to think that they are the bigger losers.

What we have lost is a good newsgroup. Why can't everyone see that when
they reply, he wins. And wins and wins.....

Folks, I'll say it _again_.

The ONLY way to get rid of a know-nothing, know-it-all, obnoxious troll, is
to IGNORE him. ALL of him. EVERY time, not just when you feel like it.

I thought we were turning a corner a couple days ago, with very few replies
to him being posted. Guess again.

It´s the main reason I´m here.

Bertie

In fact, if there is a downward component of the air's velocity that
had come from its passage over the upper surface of the airfoil, then
there had been an acceleration provided to that air -- acceleration in
this case being conventionally defined as the second time derivative
of position.

Now, if the air is accelerated downward, and it has mass, it means
there had been a force applied. The local prime mover is of course the
wing, so it must experience an upward force. Maybe you have a
different idea as to on what that equal and opposite force is
operating on -- I'd be interested in hearing about that.

There are a number of basic principles in operation here, be careful
not to paint yourself into too tight a corner unless you are quite
expert.

I am not claiming skill in this area -- physics was a minor a long
time ago -- but I remember some of the basics.

Morgans wrote:
"Bertie the Bunyip" wrote

He's an idiot, what else does one need to know?

And yet so many can not resist posting replies to his posts, either with
corrections or witty zingers.

I'm starting to think that they are the bigger losers.

What we have lost is a good newsgroup. Why can't everyone see that when
they reply, he wins. And wins and wins.....

Folks, I'll say it _again_.

The ONLY way to get rid of a know-nothing, know-it-all, obnoxious troll, is
to IGNORE him. ALL of him. EVERY time, not just when you feel like it.

I thought we were turning a corner a couple days ago, with very few replies
to him being posted. Guess again.

It´s the main reason I´m here.

Bertie

Morgans wrote:
"Bertie the Bunyip" wrote

He's an idiot, what else does one need to know?

And yet so many can not resist posting replies to his posts, either with
corrections or witty zingers.

I'm starting to think that they are the bigger losers.

What we have lost is a good newsgroup. Why can't everyone see that when
they reply, he wins. And wins and wins.....

Folks, I'll say it _again_.

The ONLY way to get rid of a know-nothing, know-it-all, obnoxious troll, is
to IGNORE him. ALL of him. EVERY time, not just when you feel like it.

I thought we were turning a corner a couple days ago, with very few replies
to him being posted. Guess again.

It´s the main reason I´m here.

Bertie