This X-24A was originally the jet-powered Martin
SV-5J, a derivative of the X-24A built for flight training. It
never flew. For display, the SV-5J has been converted to
simulate the X-24A. It was donated by Martin in 1971.
Martin X-24A
The X-24A was developed to test the flight characteristics and maneuverability of manned lifting bodies and analyze the feasibility of using these aircraft for return from space. The X-24 program concentrated on the last stage of reentry, from about 70,000 feet (21,280 meters) altitude at 1,000 mph (2,609 km/hr) to landing.