On this day in 1958, the Vought XF8U-3 Crusader III had its first flight.
The XF8U-3 was developed as a successor to the highly successful Fought F-8 Crusader and was a competitor to the McDonnell Douglas F-4 Phantom II. Although cosmetically the XF8U-3 looked similar to the F-8 and shared the older aircraft’s designation, the two aircraft shared very few parts. It was powered by a Pratt & Whitney J75-P-5A after-burning engine and was capable of top speeds of Mach 2.39, although this top speed was only reached once by the aircraft. To deal with the flight conditions encountered when flying at speeds in excess of mach 2, the Crusader III was equipped with large vertical ventral fins which rotated to a horizontal position for landing.
In flight tests the Crusader III showed a definite edge in maneuverability against the F-4 Phantom II, however the solitary pilot of the XF8U-3 could easily become overwhelmed with the workloads required to both fly the plane and fire Sparrow missile, while the F-4 Phantom II had a dedicated radar intercept officer on board.
In addition, the Phantom had a considerably larger payload and the ability to fly air-to-ground as well as air-to-air missions. For this and other reasons, the Navy chose the F-4 Phantom II over the XF8-U Crusader to replace its fleet of F-8 Crusaders. The F8U-3 program was cancelled with five aircraft built. The three that flew during flight test and the two other airframes were transferred to NASA for atmospheric testing, as the XF8-U3 was capable of flying above 95% of the Earth’s atmosphere.
NASA pilots flying the XF8U-3 from NAS Patuxent River would routinely intercept and defeat US Navy F-4 Phantom II’s in mock dogfights until repeated complaints by the Navy brought an end to the harassment by the XF8U-3 pilots. After atmospheric tests were complete, all five of the Crusader III’s were scrapped.