Gilbert XF-120 in Toward the Unknown (1956)
Largely forgotten today, Unknown remains a cult favorite of aviation buffs. Set during the heyday of experimental airplanes at Edwards Air Force Base, the movie stars a Bell X-2 and showcases a Douglas X-3 Stiletto. But the rarest bird of all is the so-called Gilbert Fighter, technically designated the XF-120. In fact, this was the last surviving Martin XB-51, a stylish three-engine, swept-wing, supersonic bomber designed to replace the A-26 Invader for night attack and close-air-support missions. The XB-51 lost out to the English Electric Canberra, which eventually entered service as the B-57 (built by Martin). One of the two XB-51 prototypes was destroyed during testing at Edwards. The other appeared in this Warner Brothers film, with no changes other than the fictitious name painted on its nose. In the movie, test pilot William Holden warns about structural overstress but is ignored, and the experimental bomber’s wings buckle in flight. Fact followed fiction, with an odd twist: After a refueling stop in El Paso, Texas, while flying to Eglin Air Force Base in Florida to shoot additional footage, the bomber crashed on takeoff, streaming wreckage as it disintegrated. Initially, identification of the aircraft was complicated because the shredded fuselage retained the Gilbert XF-120 logo.