دانلود کتاب تصاویر جنگ – موستانگ P-51

The Mustang story begins in April 1940 when British Purchasing Commission officials visiting America sought a new long-range fighter to supplement the Spitfire and Hurricane. A number of US aircraft manufacturers were called to a conference in New York on 5 April and delegates included James H. ‘Dutch’ Kindelberger, president of North American Aviation Incorporated who was accompanied by the company’s executive vice president, J. Leland Atwood. When Curtiss-Wright Corporation offered to supply the Curtiss H-87 (P-40D), which was already in production, it was suggested that North American could ease the supply problem by assisting with construction of the aircraft. Then Kindelberger offered to design and build a new and infinitely superior fighter specifically developed to meet the British requirement using the same 1,150hp Allison V-1710-39 engine. The British Purchasing Commission accepted his proposal but the contract also called for various types of other fittings and armament to be provided by the British, who specified that the cost of each aircraft should not exceed $40,000. North American’s only previous experience in fighter design and construction was limited to the NA-50A, which had been designed in 1939 for Siam. However, Kindelberger had studied accounts of air combat in Europe and had already conceived the broad outlines of a new combat-worthy fighter, designated NA-73. Also, much useful technical data was obtained from the Curtiss-Wright Corporation. The first prototype was not built from production drawings, but rather from design layouts so that a faster rate could be achieved. All told, 3,500 original drawings were required, in addition to a wind tunnel test programme and a structural test programme, which had to be virtually completed prior to the first flight. The design and production team worked sixteen hours a day, six days a week, when they finished at 1800 hours. The NA-73X prototype was assembled in an astonishing 78,000 engineering hours over 127 days, although the 1,100hp Allison V-1710-39 (F3R) engine was not yet installed, and the wheels were borrowed from an AT-6 basic trainer. After several modifications, the NA-73X was flown for the first time on 26 October 1940 from Mines Field (now Los Angeles International Airport) in the hands of project test pilot Vance Breese. The prototype showed excellent handling characteristics and early test flights proved to be a great success; the NA-73X soon achieved 382mph at 14,000 feet, which was equal to the British Spitfire. However, during the fifth flight on 20 November 1940, the NA-73X ran out of fuel after a fuel-switching error; the pilot attempted a wheels-down landing on farmland and the prototype flipped over onto its back after entering a newly ploughed field. The aircraft was deemed to be a write-off, but the British Purchasing Commission had been more than satisfied and production was assured. On 29 May 1941, 320 NA-73s were ordered. A further order was placed for 300 slightly improved NA-82 aircraft, the order being completed in July 1942. At least twenty Mustang Is were lost at sea and another ten were diverted to the Soviet Union before the end of 1941 and later used against Finland.