Upside down????

[Mike Romeo]

How does an aircraft fly upside down?

I heard the arguement once that surely when the wing is presented to the airflow the other way up the usual aerodynamic rules will still apply i.e the air will speed up over the more curved surface and the pressure become lower - on an upside down wing this will create negative lift pushing the plane into the ground.

This can't be true, so what is the explanation?

[RVR800]

Try

http://www.monmouth.com/~jsd/how/htm/title.html#mytoc

It explodes a few myths

[Dan Dare]

RVR, thats an interesting website (if a little americanised). From what I just glanced at it has some good stuff in there if you look hard enough. I didn't find much that helps with flying inverted though.

MR, aerodynamic rules do still apply, but rest easy, our inverted aerofoil can produce lift away from the ground if the angle of attack is good and positive. An assymetrical aerofoil will be less efficient inverted, but can be made to produce lift. Equally, if the aircraft is th right way up it can still produce "negative lift" which would accelerate the aircraft towards the ground (producing negative "g").

[The man formerly known as]

Its all down to angle of attack. If you get enough Alpha and enough power it will fly. (you must have experimented with your hand out of the car window)

Before the aerofoil was discovered planes had slab wings (ie flat, no curves) and they flew. The curvey bits just made it more efficient.

Some aerobatic planes (eg Extra 300) have symetric aerofoils ie not as efficient the right way up but not quite as inefficient the wrong way up.