First flew with British military serial XW654 in 1971, Delivered to the USMC as 158394 in 1972. Modified by McDonnell Douglas as a YAV-8B-2. Assigned to NASA Ames Research Center, NAS Moffett Field, CA as NASA 704 from 1984 to 1995. Used for boundary layer control, STOL and V/STOL research. Modified into the V/STOL Systems Research Aircraft (VSRA) with the installation of digital fly-by-wire controls for pitch, roll, yaw, thrust magnitude and thrust deflection, and programmable electronic head-up displays. Preserved at Aviation Challenge Museum, Huntsville, AL from 1998.

Former USMC 158394 Photographer: Tom Kaminski.

The Bell X-14A in a wind tunnel at NASA Ames. It is said to have become NASA 704 with its upgrade to X-14B in 1971 but that date is apparently wrong. Matching civil identity N704NA was registered in 1969. More Beech than Bell, the aircraft had a Bonanza wing and a Mentor tail. Two smal turbojet engines with thrust deflectors for VTOL, plus compressed-air nozzles at wingtips and tail. Photo by: Art Melliar / NASA