Bell’s last fighter, designed to replace the P-51, was the long range single seat XP-83.
On 24 March 1944 the USAAF tasked Bell to build a larger, longer-range jet fighter to superceed the P-51 Mustang. Bell assigned engineer Charles Rhodes to develop the XP-83, powered by two 1633kg thrust General Electric I-40 (later J33-GE-5) turbojets, and to be armed with six 12.7mm Browning nose machine-guns.
First flown on 25 February 1945, the first XP-83 proved underpowered and unstable. The close proximity of the two low-slung powerplants caused hot exhaust gases to buckle the tail-plane unless, during run-ups, fire trucks were used to play streams of water over the rear fuselage.
The second XP-83 was completed with a slightly different bubble canopy and extended nose to accommodate six 15.2mm guns, the increase in barrel diameter being based on anticipated firepower needs for the planned amphibious invasion of Japan. This airframe was used in gunnery tests at Wright Field, Ohio.
Modified tailpipes, angled outwards, resolved the heat/buckling problem. Wind tunnel tests showed than a 45.7mm extension of the vertical tail would assure stability, though it is not clear whether this modification was actually made.
Except range, which was 3540km with underwing drop-tanks, the Bell XP-83 offered no improvement over the Lockheed F-80 Shooting Star then in production. For the post-war fighter-escort role, the newly independent USAF turned to the North American F-82 Twin Mustang. The redesignated XF-83 operated as a flying testbed for new technology.
The first XP-83 was assigned to a ramjet engine test programme. A hatch was cut in the belly to provide entry into the aft fuselage and an engineer's station with a small port-side window, was created behind the pilot. Experimental ramjets were slung under the wings. The intent was for the XF-83 to serve as a proving vehicle for ramjet power, once aloft flying with the ramjets alone.
On 4 September 1947, just as this test programme had begun, a ramjet caught fire and flames spread to the wing. Pilot Chalmers 'Slick' Goodlin and engineer Charles Fay, without benefit of ejection seats, bailed out safely and the XF-83 was destroyed.
Engines: 2 x General Electric J33-GE-5, 1814kg
Max take-off weight: 10927 kg / 24090 lb
Empty weight: 6398 kg / 14105 lb
Wingspan: 16.15 m / 52 ft 12 in
Length: 13.66 m / 44 ft 10 in
Height: 4.65 m / 15 ft 3 in
Wing area: 40.04 sq.m / 430.99 sq ft
Max. speed: 840 km/h / 522 mph
Ceiling: 13715 m / 45000 ft
Range w/max.fuel: 2784 km / 1730 miles
Armament: 6 x 12.7mm machine-guns