Pratt & Whitney XA101
The Pratt & Whitney XA101 is an American adaptive cycle engine demonstrator being developed by Pratt & Whitney for the Lockheed Martin F-35 Lightning II and form the technological foundation for the company's XA103 propulsion system for the United States Air Force's sixth generation fighter program, the Next Generation Air Dominance (NGAD). The XA101 competes directly with the General Electric XA100.