F-15 ACTIVE/STOL/MTD aircraft
By the end of the 1980s, the F-15 had already been proven a versatile airframe, so it was a natural base for a variety of experiments.
Beginning in 1988, a modified F-15 was used for short takeoff and landing tests, as well as testing maneuverability augmenting canards. The resulting aircraft could rapidly accelerate and decelerate, as well as take off and land on shortened runways.
The same aircraft was later used as the testbed for the ACTIVE program (Advanced Control Technology for Integrated VEhicles). This was primarily a software-proving program, so no further airframe modifications were made.
The airframe was used for a number of smaller projects until its retirement in 2009, including research on compression shockwaves as well as for acoustical tests at high speeds.