test 1: model airplane on treadmill and it propelled forward
test 2: model airplane on large sheet of some material being pulled opposite direction (make shift conveyor) and airplane took off
test 3: experimental on 2000' strip of burlap or whatever it was being pulled by truck in opposite direction (make shift conveyor) airplane took off.
worth mentioning: quote from experimental pilot with ten years experience when asked what he thought would happen "I think im going to just sit here like a brick"