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Old October 3rd 07, 04:34 PM posted to rec.aviation.piloting
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Default Backwash Causes Lift?

On Oct 3, 8:15 am, Le Chaud Lapin wrote:

Actually I did because every book I read about flying skimped on the
subject. I'm going to hop over to MIT's OpenCourseWare later this
week and download their most basic course on aero/astro. Benoulli's
principle is toss around as if it were facecloth, but I'm getting the
feeling that no one is really doing the physics.


Lemme see: People have been building flying machines since the late
1800's, about 125 years now, and none of them have been interested
enough in the phenomenon of lift to do the physics? How old are you,
anyway? Many of the contributors here have been flying much longer
than you have likely been alive and have studied this in detail, and
some of them might even have doctorates in the subject. The subject of
lift has been beaten to death on this forum and if you Googled it
you'd find some good information.
Both Newton and Bernoulli are correct. Even inside a pipe the
static pressure drops as velocity increases. That's why your bottom
table jumps as you yank off the top one: you accelerated an airflow.
And in generating lift there's a displacement of air. Can't escape
that at all.
The stagnation point on a leading edge isn't right at the front.
It's slightly below the wing, and as AOA increases it moves back
underneath quite a bit. It's not all intuitive, you see, and that
intuitive understanding of some of this stuff is where people get all
messed up and think they have the answers that have escaped all the
other experts all these years. We run into this attitude rather
frequently in the flight training industry. It tends to make the
student unteachable.

Dan