Hans von Ohain was one of the inventors of jet propulsion and Eric Warsitz was the first ever to fly a jet plane on August 27, 1939. Limited edition flight-flown commemorative cover, 7.5 x 4.5, with a cachet honoring the 40th anniversary of the first jet-propelled flight, signed on the front in felt tip by Hans von Ohain and Eric Warsitz. In very fine condition. RRAuction COA.
