Bell X-14

The Bell X-14 is an American experimental aircraft built by Bell Aircraft Corporation for the National Aeronautics and Space Administration and the United States Air Force, flown for the first time in 1957 to explore vertical takeoff and landing using thrust vectoring, in which a pair of jet engines' exhaust could be redirected downward for vertical lift and then rotated rearward for conventional forward flight, rather than relying on separate lift engines or a tilting airframe. Built as a relatively simple, lightweight open-frame research aircraft rather than a prototype for any operational combat or transport role, the X-14 remained in active flight-test use for an unusually long span of years, including service helping train early astronauts in the handling characteristics later used for lunar landing simulation research, before it was damaged beyond economical repair in a landing accident.