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The Tupolev Tu-144 (NATO name: "''Charger''") is a retired jet airliner, which was the world's first commercial supersonic transport aircraft (SST). It is one of only two SSTs to enter commercial service, the other being the Anglo-French Concorde. The design, publicly unveiled in January 1962, was constructed in the Soviet Union under the direction of the Tupolev design bureau, headed by Alexei Tupolev.〔Throughout its 55-flight operational history, the Tu-144 flew at an average service altitude of and cruised at a speed of around .〔http://www.tupolev.ru/en/aircrafts/tu-144〕 The prototype first flew on 31 December 1968 near Moscow,〔 two months before the first flight of Concorde. The Tu-144 first went supersonic on 5 June 1969, and on 26 May 1970 became the first commercial transport to exceed Mach 2. A Tu-144 crashed in 1973 at the Paris Air Show, delaying its further development. The aircraft was introduced into passenger service on 1 November 1977, almost two years after Concorde, because of budget restrictions. In May 1978, another Tu-144 (an improved version, named Tu-144D) crashed in a test flight while being delivered, and the passenger fleet was permanently grounded after only 55 scheduled flights. The aircraft remained in use as a cargo aircraft until 1983, by which point a total of 102 commercial flights had been completed. The Tu-144 was later used by the Soviet space program to train pilots of the Buran spacecraft, and by NASA for supersonic research. ==Development== The Soviet government published the concept of the Tu-144 in an article in the January 1962 issue of the magazine ''Technology of Air Transport''. The air ministry started development of the Tu-144 on 26 July 1963, 10 days after the design was approved by the Council of Ministers. The plan called for five flying prototypes to be built in four years, with the first aircraft to be ready in 1966. Despite the close similarity in appearance of the Tu-144 to the Anglo-French supersonic aircraft, there were significant differences in the control, navigation and engine systems. The Tu-144 lagged behind Concorde in areas such as braking and engine control. Concorde utilized an electronic engine control package from Lucas, which Tupolev was not permitted to purchase for the Tu-144 as it could also be used on military aircraft. Concorde's designers used airliner fuel as coolant for the cabin air conditioning and for the hydraulic system (see Concorde for details). Tupolev installed additional equipment on the Tu-144 to accomplish this, increasing the weight of the airliner. Andrei N. Tupolev〔Gordon and Rigmant 2005〕 continued to improve the Tu-144 with upgrades and changes on the Tu-144 prototype. While both Concorde and the Tu-144 prototype had ogival delta wings, the Tu-144's wing lacked Concorde's conical camber. Production Tu-144s replaced this wing with a double delta wing including such conical camber, and they added a simple but practical device: two small retractable surfaces called Moustache canard, one on either side of the forward section on the aircraft, to increase lift at low speeds. Moving the elevons downward in a delta-wing aircraft increases the lift (force), but also pitches its nose downward. The canards cancel out this nose-downwards moment, thus reducing the landing speed of the production Tu-144s to , still faster than that of Concorde.〔("Ground-Effect Characteristics of the Tu-144 Supersonic Transport Airplane." ) ''NASA Dryden Center.'' Retrieved: 25 January 2011.〕 The NASA study lists final approach speeds during Tu-144LL test flights as . An FAA circular lists Tu-144S approach speed as , as opposed to Concorde's approach speed of , based on the characteristics declared by the manufacturers to Western regulatory bodies.〔("FAA Advisory Circular 150/5300-13, Airport Design, Appendix 13." ) ''FAA.'' Retrieved: 31 July 2011.〕 It is open to argument how stable the Tu-144S was at the listed airspeed. In any event, when NASA subcontracted Tupolev bureau in the 1990s to convert one of the remaining Tu-144D to a Tu-144LL standard, the procedure set by Tupolev for landing defined the Tu-144LL "final approach speed... on the order of 360 km/hr depending on fuel weight."〔("A Qualitative Piloted Evaluation of the Tupolev Tu-144 Supersonic Transport." ) ''NASA''.Retrieved: 31 July 2011.〕 Brian Calvert, Concorde's technical flight manager and its first commercial pilot in command for several inaugural flights, cites final approach speed of a typical Concorde landing to be .〔Calvert 2002, p. 109.〕 The lower landing speed compared to Tu-144 is due to Concorde's more refined design of the wing profile that provides higher lift at low speeds without degrading supersonic cruise (aeronautics) performance – a feature often mentioned in Western publications on Concorde and acknowledged by Tupolev designers as well.〔Bliznyuk 2000, p. 66.〕 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「Tupolev Tu-144」の詳細全文を読む スポンサード リンク
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