It's a shitty thought experiment which was either 1) made by someone who doesn't understand how landing gear functions, or else 2) made by someone who was being a dick about the fact that most people don't know how landing gear functions.
A plane is standing on a runway that can move (some sort of band conveyer). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off? (emphasis added)
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