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". What does you statement have to do with what I said, let alone it
being "contrary"?

--
Thomas Borchert (EDDH)