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} |} The CFM International LEAP (formerly called LEAP-X) is a high-bypass turbofan engine. It is currently under development by CFM International, a 50-50 joint venture company between GE Aviation of the United States and Snecma of France. ==Design and development== The LEAP ("Leading Edge Aviation Propulsion")〔(LEAP Turbofan Engine, History )〕 incorporates technologies that CFM developed as part of the LEAP56 technology acquisition program, which CFM launched in 2005.〔(CFM Laying the Technology Foundation for the Future ). CFM International〕 The engine was officially launched as "LEAP-X" on 13 July 2008. It is intended to be a successor to the CFM56-5B and CFM56-7B. The LEAP's basic architecture includes a scaled up version of Safran's low pressure turbine used on the GEnX engine. The fan has flexible blades manufactured by a resin transfer molding process, which are designed to untwist as the fan's rotational speed increases. While the LEAP is designed to operate at a higher pressure than the CFM-56 (which is partly why it is more efficient), GE plans to set the operating pressure lower than the maximum in order to maximize the engine's service life and reliability. Currently proposed for the LEAP is a greater use of composite materials, a blisk fan in the compressor, a second-generation Twin Annular Pre Swirl (TAPS II) combustor, and a bypass ratio around 10-11:1. GE is using ceramic matrix composites (CMC) to build the turbine shrouds.〔Norris, Guy, Hot blades, Aviation Week & Space Technology, April 27-May 10, 2015, p.55〕 These technological advances are projected to produce 16% lower fuel consumption.〔〔(New engines: flurry of activity despite downturn )〕〔(LEAP-X: Redefining Turbofan Engines for Narrowbody Aircraft )〕 Reliability is also supported by use of an eductor-based oil cooling system similar to that of the GenX, featuring coolers mounted on the inner lining of the fan duct. According to Aviation Week's article, "The eductor device produces a venturi effect, which ensures a positive pressure to keep oil in the lower internal sump."〔Norris, Guy, Pressure testing, Aviation Week and Space Technology, October 28, 2013, p. 43〕 The engine has some of the first FAA-approved 3D-printed components.〔(GE )〕 In total, 28 test engines will be used by CFM to achieve engine certification, and 32 others will be used by Airbus, Boeing and COMAC for aircraft certification and test programs.〔〔http://www.flightglobal.com/news/articles/first-leap-powered-a320neo-moved-to-flight-test-team-411466/〕 The first engine entering the test program successfully reached and sustained of thrust, required to satisfy the highest rating for the Airbus A321. The same engine ultimately reached of thrust in test runs.〔Norris, Guy, Pressure testing, Aviation Week and Space Technology, October 28, 2013, pp.42-43〕 General Electric carried out the first test flight, of a LEAP-1C, in Victorville, California, with the engine mounted on the company's Boeing 747 flying testbed, on October 6, 2014, The C version features a thrust reverser equipped with a one piece O-ring replacing a 2 piece door. The thrust reverser is deployed by the O-ring sliding aft, reducing the drag that was induced by the older design and improving efficiency.〔Norris, Guy, Boom time, Aviation Week & Space Technology, October 13, 2014, p.40〕 In April 2015, it was reported that the LEAP-1B was suffering up to a 5% shortfall on its promised reduction in fuel consumption. 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「CFM International LEAP」の詳細全文を読む スポンサード リンク
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