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The Martin B-26 Marauder was a World War II twin-engined medium bomber built by the Glenn L. Martin Company from 1941 to 1945. First used in the Pacific Theater in early 1942, it was also used in the Mediterranean Theater and in Western Europe. After entering service with the US Army, the aircraft received the reputation of a "Widowmaker" due to the early models' high accident rate during takeoffs and landings. The Marauder had to be flown at exact airspeeds, particularly on final runway approach and when one engine was out. The 150 mph (241 km/h) speed on short final runway approach was intimidating to pilots who were used to much slower speeds, and whenever they slowed down below to what the manual stated, the aircraft would stall and crash.〔Ethell 1995, p. 242.〕 The B-26 became a safer aircraft once crews were re-trained, and after aerodynamics modifications (an increase of wingspan and wing angle-of-incidence to give better takeoff performance, and a larger vertical stabilizer and rudder).〔Ethell 1995, pp. 242–243.〕 After aerodynamic and design changes, the aircraft distinguished itself as "the chief bombardment weapon on the Western Front" according to a United States Army Air Forces dispatch from 1946.〔Skaarup 2010, p. 88.〕 The Marauder ended World War II with the lowest loss rate of any USAAF bomber.〔Ethell 1995, p. 243.〕 A total of 5,288 were produced between February 1941 and March 1945; 522 of these were flown by the Royal Air Force and the South African Air Force. By the time the United States Air Force was created as an independent service separate from the Army in 1947, all Martin B-26s had been retired from US service. The Douglas A-26 Invader then assumed the B-26 designation — before officially returning to the earlier "A for Attack" designation in May 1966. ==Design and development== In March 1939, the United States Army Air Corps issued Circular Proposal 39-640, a specification for a twin-engined medium bomber, demanding a maximum speed of , a range of and a bomb load of . On 5 July 1939, the Glenn L. Martin Company submitted its design, produced by a team led by Peyton M. Magruder, to meet the requirement, the Martin Model 179. Martin's design was evaluated as superior to the other proposals and was awarded a contract for 201 aircraft, to be designated B-26.〔''Air International'' January 1988, p. 23.〕 The B-26 went from paper concept to an operational bomber in approximately two years.〔Trent 2008, p. 647.〕 Additional orders for a further 930 B-26s followed in September 1940, still prior to the first flight of the type.〔''Air International'' January 1988, p. 25.〕 The B-26 was a shoulder-winged monoplane of all-metal construction, fitted with a tricycle landing gear. It had a streamlined, circular section fuselage housing the crew, consisting of a bombardier in the nose, armed with a machine gun, a pilot and co-pilot sitting side by side, with positions for the radio operator and navigator behind the pilots. A gunner manned a dorsal turret armed with two machine guns (the first powered dorsal turret to be fitted to a US bomber), while an additional machine gun was fitted in the tail. Two bomb bays were fitted mid-fuselage, capable of carrying of bombs, although in practice such a bomb load reduced range too much, and the aft bomb bay was usually fitted with additional fuel tanks instead of bombs. The aircraft was powered by two Pratt & Whitney R-2800 Double Wasp radial engines in nacelles slung under the wing, driving four-bladed propellers. The engines were manufactured at the Ford Dearborn Engine plant in Dearborn, Michigan, USA. The wings were of low aspect ratio and relatively small in area for an aircraft of its weight, giving the required high performance, but also resulting in a wing loading of 53 lb/sq ft (259 kg/m²) for the initial versions, which at the time was the highest of any aircraft accepted for service by the Army Air Corps.〔''Air International'' January 1988, pp. 23–25.〕 The first B-26, with Martin test pilot William K. "Ken" Ebel at the controls, flew on 25 November 1940 and was effectively the prototype. Deliveries to the US Army Air Corps began in February 1941 with the second aircraft, ''40-1362''.〔 In March 1941, the Army Air Corps started Accelerated Service Testing of the B-26 at Patterson Field, Ohio. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Martin B-26 Marauder」の詳細全文を読む スポンサード リンク
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