That's a good way to look at it - and see that you are wrong <img src="/forums/images/graemlins/lol.gif" alt="" />

If I land a glider at 60 miles per hour (ground speed)on a conveyor that is moving in reverse 60 miles per hour - I go nowhere...technically i will eventually go backwards if the conveyor does not change speed.

Same principle as a hook and rope on an aircraft carrier. The static force (if thats the right term) applied to the hook is equal to or greater than that of the plane - stopping it in its tracks.

concreteprinter.com