The only way the plane will take off is if they put the conveyor on a catapult. Which they probably will do some variation of.
A plane flies because it has wings, and air flows over the wings giving it lift. If the conveyor keeps the plane from moving forward, there will be no apparent wind over the wing, other than the prop wash. this is not enough to give it lift. Of course, if you put a butt load of engines on each wing, or set the whole thing up in a wind tunnel, it just might take off. But that is not the initial assertion.