This is an artist's conception of the NASA/Lockheed Martin X-33 on the back of a modified 747 airliner.
ED97-43938-5
This is an artist’s conception of the NASA/Lockheed Martin X-33 on the back of a modified 747 airliner. This was a proposal means to move the X-33 from a landing site back to NASA’s Dryden Flight Research Center, at Edwards, CA.1997NASA Photo / › X-33 Project Description