Originally Posted by Mojo31

If the plane is moving at 100 knots in a 100 knot tailwind, how could the wings generate any lift?

I don't know the answers to these things other than what I've experienced sailing. For example, if I'm going dead down wind in a sailboat at 3 knots in a 3 knot wind, then I'm just getting pushed and the sails (foils) are not generating any lift.