Why will an aeroplane fall from the sky if it stops moving forward?

Question

Why will an aeroplane fall from the sky if it stops moving forward?

Answer 1

because the wings will stop producing lift -

the wings are shaped in such a way that as they move through the air the air pressure above the wings gets lower than the air pressure below the wings - so that produces "lift"

propellers (and helicoptor blades) actually work on the same principle

if you ever have heard the term "a stall" regarding airplanes - what that means is that the angle of the wing to the air becomes too great and it no longer can produce lift (the plane's nose is too high for instance)

it's all based on Bernoulli's Principle - see:

http://en.wikipedia.org/wiki/Bernoulli's...

http://www.pacifier.com/~mpatters/bird/f...

http://en.wikipedia.org/wiki/Stall_(flig...

EDIT: oh... and airplanes don't immediately fall - there is what's called an airplane's "glide ratio" - http://en.wikipedia.org/wiki/Glide_ratio

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Answer 2

Because when an aeroplane moves forward the wings create lift, due to air pressures above and below the wing, this lift overcomes the effect of gravity and keeps it in the air. If the airplane stops then the wings stop creating lift and gravity takes over, so it will drop to the ground. It is a bit more complicated than that but thats the basics.

Answer 3

a wing works because the air pressure below the wing is greater then the air pressure above the wing (nature abhors a vacuum), resulting in a force upward. Once the pressure drops the plane sinks and in this case drops.

there are some fighter planes that humans can't fly because the air pressure surrounding the plane is unstable and is therefor controlled remotely through the computer.

Answer 4

Because the plane has lost momentem and gravity takes over...Then it falls....

Answer 5

An aeroplane does not "fall from the sky" when it stops moving forward. Every student pilot knows this. What happens is that the wings no longer produce lift, because they produce lift by the dynamic action of the air passing over them.

But they still produce craploads of *drag*, so the aeroplane does not drop like a stone. It pretty much just feels like nothing more than a little bump and does not result in fire and brimstone. Correctly performing stalls and recoveries is a standard requirement of pilot training.