Boeing 236 / F6B / BFB-1

XF6B1

The last Boeing biplane fighter, the Model 236 single-seat shipboard fighter was designed around the 14-cylinder twin-row Pratt & Whitney R-1535 Twin Wasp Junior engine rated at 625hp at 1676m. Of all-metal construction with fabric-covered wings, the Model 236 was assigned the designation XF6B-1 by the US Navy and flew on 1 February 1933.

Armament was two 7.62mm guns and provision was made for a single 227kg bomb or two 52kg bombs, and on 21 March 1934, the prototype was assigned the new "bomber-fighter" designation of XBFB-1. The engine installation and undercarriage were refined during the test and evaluation programme, but no production was undertaken.

Engine: Pratt & Whitney R-1535 Twin Wasp Junior, 625hp
Take-off weight: 1680 kg / 3704 lb
Empty weight: 1038 kg  
Wingspan: 8.69 m / 28 ft 6 in
Length: 6.74 m / 22 ft 1 in
Height: 3.22 m / 10 ft 7 in
Wing area: 23.41 sq.m / 251.98 sq ft
Max. speed: 322 km/h / 200 mph
Range: 845 km / 525 miles