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The Bramo 323 ''Fafnir'' was a 9-cylinder radial aircraft engine of the World War II era. Based heavily on Siemens/Bramo's earlier experience producing the Bristol Jupiter under license,〔Gunston 1989, p.30.〕 the engine was not particularly modern and saw limited use. ==Design and development== Development of the 323 was the end result of a series of modifications to the original Jupiter design, which Siemens licensed in 1929. The first modifications were to "Germanize" the dimensions, producing the Sh.20 and Sh.21. The design was then bored out to produce the 950 hp (708 kW) Sh.22 in 1930. Like the Jupiter, the Sh.22 featured a rather "old" looking arrangement with rather prominent valve pushrods on the front of the engine. In the mid-1930s the Reich Air Ministry (RLM) rationalized engine naming, and Bramo was given the 300-block of numbers, the Sh.14 and Sh.22 becoming the Bramo 314 and 322 respectively. The 322 never matured and remained unreliable. The team continued work on the basic design, adding fuel injection and a new supercharger. The resulting 323 was just under 27 l in displacement, and produced 900 PS at 2,500 rpm for takeoff, improving slightly to 1,000 PS at . The reduced power at sea level was inevitable for engines with one-speed mechanically driven superchargers when they were regulated to a constant maximum boost pressure below their critical altitude. The Fafnir powered a number of German pre-war designs, including the Focke-Wulf Fw 200, Henschel Hs 126, Dornier Do 24 and Dornier Do 17, as well as the Focke Achgelis Fa 223 ''Drache'' helicopter. Its fairly poor fuel economy kept it from more widespread use, and most designs chose the similar BMW 132 instead, whose specific fuel consumption varied between 220 and 240 g/(kW•h) depending on model, whereas the early versions of the Fafnir got about 255 g/(kW•h), a poor figure for the era. The C/Ds, where the supercharger used less power, improved this to 230 g/(kW•h), but were only useful at lower altitudes. BMW bought Bramo in 1939 and continued production to supply the small number of designs that already used it, notably the Do 17. The naming at this point becomes somewhat confusing, with BMW, Bramo and Fafnir being used almost interchangeably. 5,500 were produced before the lines were shut down in 1944. 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「Bramo 323」の詳細全文を読む スポンサード リンク
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