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The Westinghouse J40 was to be a high-performance afterburning turbojet engine. It was intended by the Bureau of Aeronautics, in early 1946, to power several fighter aircraft and a bomber, with a rating of 7,500 lbf (33 kN) thrust at sea level static conditions without afterburning and 10,900 lbs thrust with afterburning. A more powerful model 9.500/13,700 lbf thrust version was intended to replace the earlier engines for the various airframes, but proved to have a flawed compressor design and lacked a suitable control system. These higher-power engines were deemed a failure, leaving the US Navy Bureau of Aeronautics with only the earlier lower-power engines. These were eventually used for early flight testing. In the case of the McDonnell F3H-1N Demon, the 10,900 lb thrust engine was used in production airframes for a very short period before the aircraft was grounded after repeated incidents caused by flying the now overweight airframe with an underpowered engine and continuing engine issues. Failures in service led to the loss of aircraft. A government investigation of the F3H-1N program issue failed to determine if pilots had been lost due solely to the engine issues. The grounded airframes were either scrapped or used for ground training. The F3H-2N used the Allison J71 engine. After the program was called a "fiasco" and an "engine flop", the J40 program was terminated in 1955, by which time all the aircraft it was to power were either grounded, cancelled or redesigned to use alternative engines. The J40's failure was among those that affected the most military programs. The program failure was primarily due to lack of investment in research and experimental resources by Westinghouse, leaving them unable to resolve the issues with the various models of the engines. In 1953 Westinghouse worked with Rolls-Royce to offer engines based on the Avon, but Westinghouse was out of the aircraft engine business by 1965 when their 6,200 lb thrust scaled-down version of the 12,000 lb Avon 300-series engine, the XJ54, also failed to find a United States market.〔(Westinghouse Electric )〕 The engine program was far larger than is commonly known, with 13 different models placed under contract, although not all entered active development. The projected need for the higher-power engines led BuAer to place a second source production contract with Ford Motor Company, Lincoln Mercury Division for both J40-WE-10 and J40-WE-12 engines. The contract was cancelled after the engines failed in development. ==Development== Westinghouse Electric Corporation established the Westinghouse Aviation Gas Turbine Division (AGT) in 1945. The J30 was the first American-designed turbojet to run, and was used in the McDonnell FH Phantom. The enlarged J34 was obsolete when introduced, but moderately successful. A new design following the rapid industry progress was needed. The J40 represented a big opportunity for Westinghouse to become a prominent player in the turbojet engine market. The U.S. Navy showed great confidence in the company when it bet the success or failure of a new generation of jets on Westinghouse over three other engine companies. It was in June 1947 that the Navy's Bureau of Aeronautics contracted for its development. The prototype engine first ran in November 1948. According to an article in the April 1949 edition of the ''Naval Aviation Confidential Bulletin'' by Lieutenant Commander Neil D. Harkleroad of the Bureau of Aeronautics Power Plant Division, "The engine has been operating successfully to date." As of that writing, the 50-hour flight substantiation test was to have been accomplished by June 1949 and the 150-hour qualification test by December 1949. The J40 was designed to deliver twice the thrust of engines currently in service, allowing the J40-WE-8 with afterburner to power many of the new Navy carrier-based fighters with a single engine. These included the Grumman XF10F Jaguar variable-sweep wing general-purpose fighter, the McDonnell F3H Demon and Douglas F4D Skyray interceptors. Growth to over 15,000 lbf (67 kN) of thrust in afterburner was projected. A version without afterburner, the J40-WE-6, was to power the Douglas A-3D Skywarrior twin-engine carrier-based bomber. The J40-8 was only a little over in diameter but long, with accessories and including the afterburner. It weighed almost 3,500 pounds (1,600 kg), the -6 being almost seven feet shorter and about 600 pounds (270 kg) lighter, since it did not have an afterburner. In 1949, a higher-power J40-WE-12 non-afterburning version (9,500 lbs thrust) with better fuel consumption was proposed for the A3D and an afterburning version (J40-WE-10) of 13,700 lbs thrust was proposed for the fighter projects. Both versions were accepted and became the engines these airframes were designed to use. The lower-power early development models were now intended to be used only for ground and initial flight testing until the high-power engines became available. 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「Westinghouse J40」の詳細全文を読む スポンサード リンク
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