In rec.aviation.student Gezellig wrote:
On Thu, 22 May 2008 10:52:15 -0500, Michael Ash wrote:

In rec.aviation.student Gig 601Xl Builder wrote:
Mxsmanic wrote:
Stealth Pilot writes:

aeroplanes fly because of lift generated by pressure differences on
the wing surfaces.

Airplanes fly because the wings divert the air through which they pass
downwards, creating a downwash and exerting a force in doing so that engenders
an opposite force that is lift.

... these pressure differences are caused by the shape
of the aerofoil of the wing ...

The air is diverted because the wing has a positve angle of attack. It can be
perfectly flat and it will still generate lift.

If that were the case a 747 would have to be producing over 250,000
pounds of force straight down. Why then am I not crushed when a 747
flies over me?

At sea level the atmosphere pushes down with about 14.7 pounds of force
for every square inch of exposed surface. On the average man, this works
out to about 43,000 pounds, all the time. Why aren't your crushed by this?

Because I eat beans?

Score yet another point for the musical fruit.

--
Mike Ash
Radio Free Earth
Broadcasting from our climate-controlled studios deep inside the Moon