The McDonnell Douglas (later Boeing) X-36 Tailless Fighter Agility Research Aircraft was a subscale prototype jet designed to fly without the traditional tail surfaces used on most aircraft. For control, a canard forward of the wing was used as well as split ailerons and an advanced thrust vectoring nozzle for directional control. The X-36 was unstable in both pitch and yaw axis, so an advanced digital fly-by-wire control system was put in place to stabilize the aircraft.

First flown on May 17, 1997, it made 31 successful research flights. It handled very well, and the program is reported to have met or exceeded all project goals. McDonnell Douglas merged with Boeing in August 1997 while the test program was in progress; the aircraft is sometimes referred to as the Boeing X-36.