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The PZL.37 ''Łoś'' ((英語:elk)) was a Polish twin-engine medium bomber, used in the defense of Poland against the Nazi German Invasion in 1939. It is sometimes〔E.g. Cynk (1971, 1973, 1990, 2007)〕 known as "PZL P-37" or "PZL P.37", but the letter "P" was generally reserved for fighters of Zygmunt Pulawski's design (such as the PZL P.11). The correct designation should be PZL.37. ==Design and development== The PZL.37 was designed in the mid-1930s at the PZL factory in Warsaw by Jerzy Dąbrowski. The first PZL.37/I prototype, fitted with a single vertical stabilizer, flew on 13 December 1936. The second prototype PZL.37/II, with twin vertical stabilizers and other improvements, was accepted for production. The first 10 serial aircraft were produced in 1938 as the PZL.37A variant with a single vertical stabilizer, however. The next 19 interim aircraft were built as PZL.37A bis, with a twin tail. They all were powered by Bristol Pegasus XII B radial engines produced in Poland under licence. The main production variant, the PZL.37B (or: Łoś II), was fitted with the twin tail and newer Pegasus XX engines. Production of PZL.37B for the Polish Air Force started in autumn 1938. During the initial period of PZL.37 service, 2 prototypes and 6 serial planes, were lost in crashes caused by technical problems, mostly with rudders. After some structural changes, the PZL.37B became a fully reliable aircraft. By the outbreak of World War II, about 92 PZL.37s had been produced and given to the Air Force, and a further 31 were in different phases of production. Before the war, the PZL.37B Łoś was one of the world's most modern bombers. It was able to carry a heavier bombload than similar aircraft, for example the Vickers Wellington, though the size of the bombs was limited. Smaller than most contemporary medium bombers, it was relatively fast and easy to handle. Thanks to a landing gear with double wheels it could operate from rough fields or meadows. Typically for the late 1930s, its defensive armament consisted of only 3 machine guns, which proved too weak against enemy fighters. Starting with a presentation at a salon in Belgrade in June 1938 and in Paris in November, the PZL.37 met with a huge interest. For export purposes, new variants were developed: the PZL.37C with Gnome-Rhone 14N-0/1 engines of 985 cv (971 BHP, 724 kW), maximum speed 445 km/h and the PZL.37D with 14N-20/21 of 1,065 cv (1,050 BHP, 783 kW), maximum speed 460 km/h. In 1939, 20 PZL.37Cs were ordered by Yugoslavia, 12 by Bulgaria, 30 PZL.37Ds and license by Romania and 10, raw materials and parts for next 25 and license by Turkey and, finally, 12 aircraft for Greece.〔Glass (2008), p.97〕 Belgian company Renard received permission for license production 20-50 aircraft for Republican Spain but resigned in 1939. Also Denmark, Estonia, Finland and Iran were negotiating. The Polish military weren't allowed a deal with Iran due to "lack of production abilities".〔 The outbreak of the war prevented the production of these aircraft. At that time, PZL developed the next variant for the Polish airforce, the PZL.49 Miś, but this was not completed before the war. Having slightly bigger dimensions, Miś ("Bear") was to be fitted with Bristol Hercules II engines of 1,350 BHP (1,370 cv, 1,007 kW), maximum speed 520 km/h and an upper turret. 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「PZL.37 Łoś」の詳細全文を読む スポンサード リンク
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