It wouldn't, ill explain better. The plane is still ok? It's rolling along but it counter acted by the conveyor. Now, to lift a plane you have to create lift commonly created by the wings and the aerofoil shape and not the engines. (notice the engines are pointed forwards not upwards) As the plane moves through the air it is split by the wing, below the wing air is forced to move down, lifting the plane (rather then moving the floor down). In this situation no air is flowing towards the plane as it is not moving through it, thus no air can be force down and no lift. P.S. This isnt bullshit, ive got qualifications in airmanship etc EDIT: ESP is extra sensory perception (how you can feel things like people looking at you etc)