Heavily-modified pre-production F-15 (TF-15A - the first two-seat F-15B prototype).
Under the Air Force STOL/MTD program, the aircraft was fitted canard foreplanes and 2-D thrust vectoring nozzles, allowing it to take off at speeds as low as 42 mph, reduce take-off rolls 25%, land in 1.650 ft (vs the usual 7,500 ft), and reverse thrust in flight for rapid deceleration. The program lasted from 1988 to 1991.
In 1993, NASA acquired the aircraft from McDonnell Douglas. 3-D vectoring nozzles were added to the engines, as well as advanced control-logic programming.
This same aircraft has been subsequently modified and used in the F-15 IFCS (Intelligent Flight Control System - 1999-2008), SBRDC/ECANS (Space-Based Range Demonstration and Certification/Exploration Communications and Navigation Systems 2006-2007), HISTEC (High Stability Engine Control), and High-Speed Research Acoustics (1997) programs. The aircraft was retired in 2009.