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The Horten H.IX, RLM designation Ho 229 (often called Gotha Go 229 because of the identity of the chosen manufacturer of the aircraft) was a German prototype fighter/bomber designed by Reimar and Walter Horten and built by Gothaer Waggonfabrik late in World War II. It was the first pure flying wing powered by jet engines.〔Green 1970, p. 247.〕 The design was a response to Hermann Göring's call for light bomber designs capable of meeting the "3×1000" requirement; namely to carry of bombs a distance of with a speed of . Only jets could provide the speed, but these were extremely fuel-hungry, so considerable effort had to be made to meet the range requirement. Based on a flying wing, the Ho 229 lacked all extraneous control surfaces, lowering drag. It was the only design to come even close to the 3×1000 requirements and received Göring's approval. Its ceiling was .〔Boyne 1994, p. 325.〕 Since the appearance of the B-2 Spirit flying-wing stealth bomber in the 1990s, its similarities in role and shape to the Ho 229 has led many to retrospectively describe the Ho 229 as "the first stealth bomber".〔 A static reproduction of the only surviving Ho 229 prototype, the Ho 229 V3, in American hands since the end of World War II was constructed in the very early 21st century and later tested by the U.S. military, who found the basic shape, paint and laminating adhesive composition of the mockup copy would provide for 37% reduction in detection range against the British Chain Home radar of the 1940s, but no significant stealth benefit against most other contemporary radar systems.〔 ==Design and development== In the early 1930s, the Horten brothers had become interested in the flying wing design as a method of improving the performance of gliders. The German government was funding glider clubs at the time because production of military and even motorized aircraft was forbidden by the Treaty of Versailles after World War I. The flying wing layout removes any "unneeded" surfaces and, in theory at least, leads to the lowest possible weight. A wing-only configuration allows for a similarly performing glider with wings that are shorter and thus sturdier, and without the added drag of the fuselage. The result was the Horten H.IV. In 1943, ''Reichsmarschall'' Göring issued a request for design proposals to produce a bomber that was capable of carrying a load over at ; the so-called "3×1000 project". Conventional German bombers could reach Allied command centers in Great Britain, but were suffering devastating losses from Allied fighters. At the time, there was no way to meet these goals—the new Junkers Jumo 004B turbojets could provide the required speed, but had excessive fuel consumption. The Hortens concluded that the low-drag flying wing design could meet all of the goals: by reducing the drag, cruise power could be lowered to the point where the range requirement could be met. They put forward their private project, the H.IX, as the basis for the bomber. The Government Air Ministry (''Reichsluftfahrtministerium'') approved the Horten proposal, but ordered the addition of two 30 mm cannons, as they felt the aircraft would also be useful as a fighter due to its estimated top speed being significantly higher than that of any Allied aircraft. The H.IX was of mixed construction, with the center pod made from welded steel tubing and wing spars built from wood. The wings were made from two thin, carbon-impregnated plywood panels glued together with a charcoal and sawdust mixture. The wing had a single main spar, penetrated by the jet engine inlets, and a secondary spar used for attaching the elevons. It was designed with a 7g load factor and a 1.8× safety rating; therefore, the aircraft had a 12.6g ultimate load rating. The wing's chord/thickness ratio ranged from 15% at the root to 8% at the wingtips.〔 The aircraft utilized retractable tricycle landing gear, with the nosegear on the first two prototypes sourced from a He 177's tailwheel system, with the third prototype using an He 177A main gear wheelrim and tire on its custom-designed nosegear strutwork and wheel fork. A drogue parachute slowed the aircraft upon landing. The pilot sat on a primitive ejection seat. A special pressure suit was developed by Dräger. The aircraft was originally designed for the BMW 003 jet engine, but that engine was not quite ready, and the Junkers Jumo 004 engine was substituted.〔 Control was achieved with elevons and spoilers. The control system included both long-span (inboard) and short-span (outboard) spoilers, with the smaller outboard spoilers activated first. This system gave a smoother and more graceful control of yaw than would a single-spoiler system.〔 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「Horten Ho 229」の詳細全文を読む スポンサード リンク
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