Thread: Something to think about

This has caused senseless debate on other forums which I find most amusing

Have a think about it before answering

A jetplane is standing on a runway that can move (some sort of conveyor belt). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyor has a control system that tracks the plane's speed and tunes the speed of the conveyor to be exactly the same (but in the opposite direction).

Can the plane take off?

no, as planes gain lift due to pressure differences between the underside and top of the wing

if the plane is stationary relative to the air around it, then it won't gain lift

^ What he said.

A plane needs air flowing across it`s wings to generate lift. If it stays motionless relative to the air, it`s not going anywhere.

Originally Posted by Spartiate

^ What he said.

A plane needs air flowing across it`s wings to generate lift. If it stays motionless relative to the air, it`s not going anywhere.

But of course giving the physics of aerodynamics, the lift must be greater than the weight and general speed of direction of the aircraft in order to generate the necessary situation that would cause the aircraft to become airborne hence it would not take off.

Originally Posted by KuRoSaKi

But of course giving the physics of aerodynamics, the lift must be greater than the weight and general speed of direction of the aircraft in order to generate the necessary situation that would cause the aircraft to become airborne hence it would not take off.

can you say that again....in English

Originally Posted by Ynot

can you say that again....in English

My thoughts exactly . I think he was trying to prove me wrong by reformulating what I said...

I'm in agreement with the above people. If take-off was directly linked to the speed of the propellers or propulsion forward, it could take off right away without a runway. All that the moving conveyer belt is doing is letting the plane get up to maximum power in a stationary spot. It's not any different than if it was just tied down. The air is not moving with the conveyer belt. If it was, then it could take off.