The first flight was made by F5D-1 (Bu. No. 139208) on 21 April 1956 and was supersonic; the aircraft proved easy to handle and performed well. After four aircraft had been constructed, however, the Navy cancelled its order. The stated reason was that the aircraft was too similar to the already-ordered
Vought F8U Crusader, but it is believed by some historians that politics played as big a part; Douglas was already building a very large proportion of the Navy's planes, and giving them the F5D contract would have made it even closer to monopoly. The project test pilot was
Lt. Cmdr Alan B. Shepard Jr. whose report stated that it was not needed by the Navy. One F5D crashed during testing by the Navy.
NASA use for NASA, on display at the
Armstrong Air and Space Museum The four aircraft continued to fly in various military test programs. Two were grounded in 1961 (likely 139209 and 142349 which had been designated for spare parts in 1958), but the other two: F5D-1 (Bu. No. 139208) NASA 212, later becoming NASA 708 and F5D-1 (Bu. No. 142350) NASA 213, later becoming NASA 802 continued to fly. Transferred to
NASA in the early 1960s, NASA 212 was used as a testbed for the American
supersonic transport program, fitted with an
ogival wing platform (the type eventually used on
Concorde; data from the program was shared with the European designers), as well as being used as a vision field test platform for the
X-20 Dyna-Soar. This aircraft was retired in 1968. NASA 802 was used for simulation of abort procedures for the X-20, because it had a very similar shape and handling characteristics. Following the DynaSoar cancellation, it was used as a
chase plane and for various other programs until it was retired in 1970. ==Surviving aircraft==