It would seem to me that if you fly from point a to point b following the rotation of the earth, you'd have to go faster than this rotation to move forward. For example, if the earth spins at 1,040/mph, then wouldn't a plane have to go faster than this just to escape the spin of the earth? I get that when the plane LEAVES the earth it moves at its speed PLUS the rotation of the earth, but surely the effect of the earth's momentum from its spin on the plane would decrease and go away very quickly and predictably. Also, it would seem to me that if you made a trip following the spin of the earth and it took 10 hours (random example) then the trip back, going against the spin of the earth should be a lot faster? When I say a lot faster, I mean 1,040/mph faster. Surely, going against the spin, the momentum of the earth's spin on the plane would be irrelevant to the plane, or perhaps even negative? Can any one help me understand this in simple english?