A major modification of the FR-1 Fireball, the Model 29 resulted from a Bureau of Aeronautics requirement for a single-seat fighter combining a turboprop with a turbojet. Assigned the designation XF2R-1 and later to become known unofficially as the "Dark Shark", the single prototype utilised the fifteenth FR-1 production airframe and retained that fighter's J31-GE-3 turbojet, mated with a General Electric XT31-GE-2 turboprop developing 1,700hp plus 227kg of residual thrust.
Although lacking the wing folding and the catapult and arrester gear standard on the FR-1, the XF2R-1 weighed 473kg more than its predecessor when it flew for the first time in November 1946. The XT31 drove a propeller with four square-tipped hollow-steel blades which could be fully feathered or reversed to zero blade angle extremely rapidly, the drag of the flatter blade angle serving as an effective air brake for landing. By comparison with the FR-1, the vertical tail surfaces of the XF2R-1 were enlarged to compensate for the lengthening forward to accommodate the turboprop, but the airframe of the later fighter was similar in most other respects. The XF2R-1 underwent extensive testing at Muroc Dry Lake, but no further development was undertaken.
Max take-off weight: 4990 kg / 11001 lb
Wingspan: 12.80 m / 42 ft 0 in
Length: 10.97 m / 36 ft 0 in
Height: 4.27 m / 14 ft 0 in
Wing area: 28.33 sq.m / 304.94 sq ft
Max. speed: 800 km/h / 497 mph
Ceiling: 11920 m / 39100 ft