Quote Originally Posted by so_jdm View Post
if there isnt any air flowing under the wings to create lift then the plane wont take off...watch the mythbusters clip, the plane is clearly moving forward in the video fast enough to create lift. if a plane was on a conveyor and sitting still then how could it take off? if this was the case why would a plane need a runway to take off? wouldnt it just throttle wide open and just go up into the air?
youre mixing the argument.

A plane needs lift or air over its wings, which is why we have a runway. The ENGINES ON THE WINGS propel the aircraft down the runway which creates lift and it takes off.

If a plane was on a conveyor belt, it would also take off, because the speed at which the conveyor matches the planes wheels, means, its traveling, which means there will be air over the wings which means lift.

what screws most people up is for some reason the conveyor belt matching the speed of its wheels somehow means the plane is stationary , which isnt true. it isnt a car. the engines are pushing the plane forward regardless, and there is air/wind created.

to answer your question, if airports built tons of conveyor belts that could magically match the speed of a planes wheels, then yes, no runways would be needed. But i suspect concrete is much cheaper and efficient at doing the job.