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Wing Lift
I had to jump in on this one - sorry.
The equation for the lift generated by an airfoil is:
Lift = 0.5 * CL * (AirDensity) * (Wing Area) * V^2
Where CL is the coefficient of lift and V is the airspeed over the airfoil.
From the above formula it is obvious that as airspeed increases lift also increases.
What is not obvious is how CL is determined. CL is a function of the wing shape AND the angle of attack. For actual airfoils, CL is determined experimentally in a wind tunnel for all angles of attack (i.e. they make a CL vs. angle of attack graph). For thin airfoils and small angles of attack, you can approximate CL with the following formula:
CL = 2*pi*(Angle of Attack) [angle of attack must be in radians]
How exactly is lift created? That is a debate that will go on forever. It is partially Bernoulli effect and partially Newton's 2nd Law - how much of each is subject to debate. Actually, some aerodynamicists have suggested that in the case of an airfoil, one principal can be used to explain the other. In all honesty, it's not really all that important as long as lift can be calculated accurately.
Someone made a statement about flaps. Flaps are used to increase the angle of attack of the airfoil and change its camber (shape). This is done so that the airplane can get larger amounts of lift at slower airspeeds and lower deck angles (like what is required during landing). By changing the wing camber, flaps also increase the stall speed of the airplane (which is also good for landings since it allows the plane to land at a slower speed). Flaps also add a lot of drag which allows the plane to make a steeper approach without having to do a forward slip (which are fun for the pilot but they tend to freak out the passengers).
-Chris
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