The Vought F-8 Crusader (originally F8U) is a single-engine, supersonic, carrier-based air superiority jet aircraft built by Vought for the United States Navy and United States Marine Corps (replacing the Vought F7U Cutlass), and for the French Navy. The first F-8 prototype was ready for flight in February 1955. The F-8 served principally in the Vietnam War. The Crusader was the last American fighter with guns as the primary weapon, earning it the title "The Last of the Gunfighters".