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The Lockheed P-80 Shooting Star was the first jet fighter used operationally by the United States Army Air Forces (USAAF).〔Green and Swanborough 2001, p. 345.〕 Designed and built by Lockheed in 1943 and delivered just 143 days from the start of the design process, production models were flying but not ready for service by the end of World War II. Designed with straight wings, the type saw extensive combat in Korea with the United States Air Force (USAF) as the F-80. America's first successful turbojet-powered combat aircraft, it helped usher in the "jet age" in the USAF, but was outclassed with the appearance of the swept-wing transonic MiG-15 and was quickly replaced in the air superiority role by the transonic North American F-86 Sabre. The F-94 Starfire, an all-weather interceptor on the same airframe, also saw Korean war service. The closely related T-33 Shooting Star trainer would remain in service with the U.S. Air Force and Navy well into the 1980s, with the last NT-33 variant not retired until April 1997. Many still serve in a military role in foreign air arms or are in private hands. ==Design and development== The XP-80 had a conventional all-metal airframe, with a slim low wing and tricycle landing gear. Like most early jets designed during World War II—and before the Allies captured German research data that showed the speed advantages of swept-wings—the XP-80 had straight wings, similar to previous propeller-driven fighters. It was the first operational jet fighter to have its engine in the fuselage, a format previously used in the pioneering German Heinkel He 178 V1 of 1939, and the slightly later British Gloster E.28/39 demonstrator of 1941. Other early jets generally had two engines because of their limited power, these being mounted in external nacelles for easier maintenance. With the advent of more powerful British jet engines, fuselage mounting was more effective, and it was used by nearly all subsequent fighter aircraft. Concept work began on the XP-80 in 1943 with a design being built around the blueprint dimensions of a British Halford H-1 B turbojet (later called the de Havilland Goblin), a powerplant to which the design team did not have actual access. Lockheed's team, consisting of 28 engineers, was led by the legendary Clarence L. "Kelly" Johnson. This teaming was an early product of Lockheed's Skunk Works, which surfaced again in the next decade to produce a line of high-performance aircraft beginning with the F-104. The impetus for development of the P-80 was the discovery by Allied intelligence of the Me 262 in spring 1943, which had made only test flights of its own first quartet (the V1 through V4 airframes) of design prototypes at that time, all fitted with retracting taildragger landing gear. After receiving documents and blueprints comprising years of British jet aircraft research, the commanding General of the Army Air Forces, Henry H. Arnold, believed an airframe could be developed to accept the British-made jet engine, and the Materiel Command's Wright Field research and development division tasked Lockheed to design the aircraft. With the Germans and British clearly far ahead in development, Lockheed was pressed to develop a comparable jet in as short a time as possible. Kelly Johnson submitted a design proposal in mid-June and promised that the prototype would be ready for testing in 180 days. The Skunk Works team, beginning 26 June 1943, produced the airframe in 143 days, delivering it to Muroc Army Airfield on 16 November. The project was so secret that only five of the more than 130 people working on it knew that they were developing a jet aircraft, and the British engineer who delivered the Goblin engine was detained by the police because Lockheed officials could not vouch for him.〔Felton, James. ("Shooting Star." ) ''Life,'' 13 August 1945, pp. 43–46. Retrieved: 25 November 2011.〕 After the engine had been mated to the airframe, foreign object damage during the first run-up destroyed the engine, which delayed the first flight until a second engine (the only other extant)〔Gunston 1989, p. 59.〕 could be delivered from Britain.〔Heppenheimer, T.A. ("The Jet Plane is Born." ) ''American Heritage magazine,'' Fall 1993. Volume 9, Issue 2. Retrieved: 1 August 2011.〕 The first prototype (44-83020) was nicknamed ''Lulu-Belle'' (also known as "the Green Hornet" because of its paint scheme). Powered by the replacement Halford H1 taken from the prototype de Havilland Vampire jet fighter, it first flew on 8 January 1944, with Lockheed test pilot Milo Burcham at the controls. Following this flight, Johnson said, "It was a magnificent demonstration, our plane was a success – such a complete success that it had overcome the temporary advantage the Germans had gained from years of preliminary development on jet planes." The donated British jet program data had no doubt proved invaluable. In test flights, the XP-80 eventually reached a top speed of at , making it the first turbojet-powered USAAF aircraft to exceed 500 mph in level flight, following the August 1944 record flight of by a special high-speed variant of the Republic P-47 Thunderbolt. Contemporary pilots, when transitioning to pioneering jets like the Shooting Star, were unused to flying at high speed without a loud reciprocating engine and had to learn to rely on the airspeed indicator. The second prototype, designated XP-80A, was designed for the larger General Electric I-40 engine (an improved Rolls-Royce Derwent, later produced by Allison as the J33). Two aircraft (44-83021 and 44-83022) were built. 44-83021 was nicknamed the ''Gray Ghost'' after its "pearl gray" paint scheme, while 83022, left unpainted for comparison of flight characteristics, became known as the ''Silver Ghost''. The XP-80A's first test flight was unimpressive, but most of the problems with the design were soon addressed and corrected in the test program. Initial opinions of the XP-80A were not positive, with Lockheed Chief Engineering Test Pilot Milo Burcham commenting that an aircraft he very much enjoyed (powered by the Halford engine) had now become a "dog." The XP-80As were primarily testbeds for larger, more powerful engines and air intake design, and consequently were larger and 25% heavier than the XP-80. The P-80 testing program proved very dangerous. Burcham was killed on 20 October 1944 while flying the third YP-80A produced, 44-83025. The ''Gray Ghost'' was lost on a test flight on 20 March 1945, although pilot Tony LeVier escaped. Newly promoted to chief engineering test pilot to replace Burcham, LeVier bailed out when one of the engine's turbine blades broke, causing structural failure in the aircraft's tail. LeVier landed hard and broke his back, but returned to the test program after six months of recovery. The top-scoring World War II USAAF ace Major Richard Bong was also killed on an acceptance flight of a production P-80 in the United States on 6 August 1945. Both Burcham and Bong crashed as a result of main fuel pump failure. Burcham's death was the result of a failure to brief him on a newly installed emergency fuel pump backup system, but the investigation of Bong's crash found that he had apparently forgotten to switch on this pump, which could have prevented the accident. He bailed out when the aircraft rolled inverted but was too close to the ground for his parachute to deploy. After the war, the USAAF compared the P-80 and Me 262 concluding, "Despite a difference in gross weight of nearly , the Me 262 was superior to the P-80 in acceleration, speed and approximately the same in climb performance. The Me 262 apparently has a higher critical Mach number, from a drag standpoint, than any current Army Air Force fighter."〔Ethell and Price 1994, p. 180.〕 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「Lockheed P-80 Shooting Star」の詳細全文を読む スポンサード リンク
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