Even as a child, one of the exciting activities was to launch airplanes, which we made, using only paper on our own. Someone had an airplane flying far, someone not so much, but it was an exciting and entertaining activity. We could get carried away with this business for hours, and the most sophisticated inventors came up with additions to aircraft in the form of tails, fenders, and other elements of a real aircraft. Of course, this could not prolong the flight, it even slowed it down, but nevertheless, it