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A Blended wing body (BWB or Hybrid Wing Body, HWB〔) is a fixed-wing aircraft having no clear dividing line between the wings and the main body of the craft. The form is composed of distinct wing and body structures, though the wings are smoothly blended into the body, unlike a flying wing which has no distinct fuselage.〔Crane 1997, p. 224.〕 A BWB design may or may not be tailless. The potential advantages of the BWB approach are efficient high-lift wings and a wide airfoil-shaped body. This enables the entire craft to generate lift, potentially reducing the size and drag of the wings. A blended wing body can have a lift-to-drag ratio significantly greater than a conventional craft, offering improved fuel economy. The BWB configuration is used for both aircraft and underwater gliders. ==History== The 1924 Westland Dreadnought was built on the basis of the theories of M. Woyevodsky after wind tunnel tests. It stalled on its first flight, severely injuring the pilot, and the project was shelved by the British Air Ministry. The Miles M.30 "X Minor" of the early 1940s was an experimental aircraft to test the blended wing fuselage design for a proposed large airliner. The McDonnell XP-67 prototype interceptor also flew in 1944 but did not come up to expectations. NASA studied the concept more recently with a computer stabilized 17-foot model (6% scale) called BWB-17, built by Stanford University, which was flown in 1997 and showed good handling qualities.〔Liebeck 2004, p. 16.〕 From 2000 NASA went on to develop a remotely controlled model with a 21 ft (6.4 m) wingspan. This research is focused on establishing the base data concerning the lift, stall and spin characteristics inherent in a Blended Wing Body design. NASA has also jointly explored BWB designs with the X-48 unmanned aerial vehicle.〔("A flight toward the future." ) ''Boeing'', August 7, 2012 Retrieved: November 23, 2012.〕 Studies suggest that BWB aircraft, configured for passenger flight, could carry from 450 to 800 passengers and achieve fuel savings of over 20 percent.〔Liebeck 2004, p. 21.〕 Other suggestions are better access to emergency exits.〔Liebeck 2004, p. 24.〕 Unfortunately potential passengers disliked the internal seating arrangements and the program changed its focus toward cargo aircraft. 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「blended wing body」の詳細全文を読む スポンサード リンク
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