Nasa has some great tutorials on aerodynamics, rockets,
etc. Check this page, then hit the 'next' arrow at
the bottom. Also, bounce around the text links. Good
stuff. Their foilsim site is fun, too.

http://www.grc.nasa.gov/WWW/K-12/airplane/wrong1.html



At 23:30 09 January 2006, 1moclimb wrote:
Bernoulli is not explaining 70% of the lift an ordinary
airfoil
generates. Bernoulli completely fails when using a
flat plate which
creates plenty of lift at normal angles of attack.
Newton, bah humbug!
The key to understanding lift is circulation, nothing
else gives
compliance with wind tunnel and test data.
Problem is that it takes about 20 minutes to read through
the whole
story and many people give up before they understand.
Here is by far
the best explanation I have found:
http://www.av8n.com/how/htm/airfoils.html
This guy put an entire book about flight training on
the web, God bless
him!
He disposes with many myths that simple minded and
uneducated wannabe
physicists promote, you gotta love it!
Ken, I know you as a reasonably smart guy, you're gonna
figure it out!

Herb, J7

Capt. Geoffrey Thorpe wrote:
Spell checking is left as an excercise for the reader.
'Ken Kochanski (KK)' wrote in message
oups.com...

OK, what is the better explanation to give fledgling
students. Should
you say the wing deflects/pushes/thrusts the air
down to hold the
aircraft up ... or should you say the wing/airflow
creates a low
pressure area that sucks the wing/aircraft upwards.

Like many people, Bernoulli was the initial and only
explanation I was
aware of ... but I now think it is easier and more
accurate to explain
that a wing/airfolil pushes the air downward. Yes,
you do have
pressure differences, but that is just an artifact
of the process.

A Bernoulli based explanation seems to create some
inconsistencies.


Berhoulli's equation (pressure + (1/2 *density* velocity
squared)
+(densty*g*elevation) = constant) is simply a special
case of Newtons law
applied to ideal gasses under specific circunstances.

So, no inconsistancies, no problems.

Air is deflected. Delta pressures are created.


--
Geoff
the sea hawk at wow way d0t com
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