Lockheed Martin X-35B STOVL

Throughout its test program, the X-35B accomplished several critical milestones, including the first successful transition from conventional flight to hovering and back in a single mission on July 20, 2001. It successfully executed vertical landings, short takeoffs, and supersonic flight, demonstrating that a single aircraft design could satisfy the diverse needs of multiple military services. The achievements of the X-35B's demonstrations contributed to Lockheed Martin's victory in the Joint Strike Fighter competition over Boeing's X-32, which led to the development of the production F-35B Lightning II. The X-35B's test flights validated technologies that established the F-35B as the first operational supersonic STOVL stealth fighter.

The Lockheed Martin X-35B served as the Short Take-Off and Vertical Landing (STOVL) demonstrator variant of the X-35 Joint Strike Fighter prototype program during the late 1990s and early 2000s. Developed as part of the competition that ultimately resulted in the F-35 Lightning II program, the X-35B aimed to demonstrate the feasibility of STOVL operations for a multi-role stealth fighter. The aircraft incorporated an innovative lift-fan system situated behind the cockpit, combined with a rotating rear nozzle and wingtip reaction control jets, which enabled it to transition between conventional and vertical flight modes. This complex propulsion system was essential to fulfill the U.S. Marine Corps and Royal Navy requirements for operations from amphibious assault ships and smaller aircraft carriers.