Thomas Borchert wrote:
Bob,

On the contrary, the problem clearly states that the conveyor is moving at
the speed that the plane is moving (but in the opposite direction).


Huh? The OP was saying "If you have a conveyoer which always reduces the
airplane's movement to zero", to which I said "the original question doesn't
say that".

I did not say that, either. I said the conveyer was moving at the speed
the airplane is moving, but in the opposite direction. I did not say
that the conveyer reduced the airplane's movement to zero, an
impossibility short of tethering the airplane.