Мартин XB-51: Американский экспериментальный штурмовик

American bomber/attack aircraft prototype

The Martin XB 51 was an American trijet ground attack aircraft. It was designed in 1945 and made its maiden flight in 1949. It was originally designed as a bomber for the United States Army Air Forces under specification V 8237 1 and was designated XA 45. The "A" ground attack classification was eliminated the next year, and the XB 51 designation was assigned instead. The requirement was for low level bombing and close support. The XB 51 lost out in evaluation to the English Electric Canberra which built by Martin entered service as the Martin B 57 Canberra.

This unorthodox design, first flying on 28 October 1949, was fitted with three General Electric J47 engines an unusual number for a combat aircraft two underneath the forward fuselage in pods, and one at the extreme tail with the intake at the base of the tailfin. The combination of variable incidence and slotted flaps gave a shorter takeoff run. The main landing gear consisted of dual wheel sets in tandem in the fuselage, similar to the Boeing B 47 Stratojet, with outrigger wheels at the wingtips (originally proved on a modified Martin B 26 Marauder named "Middle River Stump Jumper"). The XB 51 was a large but aerodynamically "clean" design which incorporated nearly all major systems internally. Eight 20 mm cannon mounted in the nose would have been installed in production aircraft. Both crew members were provided with a pressurized, air conditioned environment, equipped with upward firing ejection seats. The XB 51 was the first Martin aircraft equipped with ejection seats, these being of their own design.