The Lockheed Star Clipper was a proposed Earth-to-orbit spaceplane based on a large lifting body spacecraft and a wrap-around drop tank. Originally proposed during a United States Air Force program in 1966, the basic Star Clipper concept lived on during the early years of the NASA Space Shuttle program, and as that project evolved, in a variety of new versions like the LS-200.
Although the Star Clipper design did not progress far in the Space Transportation System (STS) program, it had an enormous effect on the emerging Space Shuttle design. The detailed study of the cost advantages of the drop tank design demonstrated a dramatic reduction in development risk, and as a result, development costs. When funding for STS development was cut, the drop tank was taken up as a way to meet the developmental budgets, leading to the semi-reusable Space Shuttle design.