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The Martin Model 167 was an American-designed light bomber that first flew in 1939. It saw action in World War II with France and the United Kingdom, where it was called the Maryland. ==Design and development== In response to a U.S. Army Air Corps light bomber requirement issued in 1938, the Glenn L. Martin Company produced their Model 167, which was given the official designation XA-22. Martin's design was a twin-engine fully metallic monoplane, capable of around 310 mph (500 km/h) and carrying a crew of three. The bombardier sat in the nose below the cockpit, and self-defense was provided by a mid-upper twin-machine gun turret, as well as four forward firing light machine guns in the wings. The XA-22 was not adopted for operational service in the U.S., as the contract was won by Douglas with its DB-7, but Martin received foreign orders, and about 450 of these relatively fast, twin-engined bombers were built. The prototype Model 167W was powered by twin-row Pratt & Whitney R-1830-37 “Twin Wasp” engines, which were replaced in French production aircraft by single-row Wright “Cyclone 9” engines (the Twin Wasps were then restored for the British Maryland). All versions of the Model 167 were armed with six machine guns, four fixed guns in the wings (mainly for ground attack), one dorsal gun and one ventral gun. In the prototype these guns were all 0.30 in Browning machine guns. The dorsal gun was mounted in a fully retractable turret. The French aircraft used license built Belgian Fabrique Nationale FN-Brownings, and used a lighter semi-retractable dorsal turret. The weight saved helped to increase the top speed to 288 mph. The Model 167 was a fairly typical twin engined bomber. The crew of three were carried in two isolated compartments – pilot and bombardier in the nose and the gunner in a separate rear compartment, isolated by a bulkhead. The most unusual feature of the Model 167 was the very narrow fuselage. Glenn L. Martin doubled the size of their Baltimore factory, and built all 115 aircraft in six months, but they were then prevented from delivering them by a US arms embargo. Despite this the French placed an order for another 100 aircraft. The embargo was finally lifted in October 1939, and the 115 aircraft from the first order were delivered by the end of November 1939. After this impressively speedy start, things slowed down, and only 25 of the second batch of aircraft had reached France before the Armistice of June 1940. 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 Maryland」の詳細全文を読む スポンサード リンク
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