The XFV-1 shown here was one of two vertical take off fighters designed around the 5,850 hp Allison XT40 turboprop engine. While the Lockheed design never demonstrated the transition from vertical to horizontal flight, the rival Convair XFY-1 successfully achieved vertical take offs and landings and transition to them from horizontal flight. However, both projects proceeded no further than the prototype stage. (US National Archives)
