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The de Havilland DH.88 Comet was a twin-engined British aircraft designed for the 1934 MacRobertson Air Race. Three examples took part in the race and one of them won it. The type set many aviation records during the race and afterwards, as a pioneer mail plane. The modern features and clean lines of the DH.88, especially in the striking colours of ''Grosvenor House'', the race winner, make it a true design classic.〔Allaz and Skilbeck 1998, pp. 94–95.〕 ==Design and development== The MacRobertson International Air Race, a race between England and Melbourne to be held in October 1934 to celebrate the 100th anniversary of the State of Victoria, was announced in 1933.〔Lewis 1970, p. 257.〕〔Jackson 1987, p. 356.〕〔("The England–Australia Race: £10,000 for Fastest Flight from London to Melborne" ). ''Flight'', Vol. XXV, No. 1284, 3 August 1933, p.770.〕 Despite previous British air racing successes, culminating in 1931 in the outright winning of the Schneider Trophy, there was no British aeroplane capable of putting up a challenge over the MacRobertson course with its long overland stages. In January 1934, the de Havilland company stepped into the breach when it offered to design a aircraft to compete in the race and produce a limited run if three were ordered by February 1934. The sale price was to be £5,000 each (approximately £}} in , when adjusted for inflation). This would by no means cover the aircraft's development costs.〔〔Ramsden ''Aeroplane Monthly'' May 1988, p. 279.〕 Three orders were indeed received, and de Havilland set to work. The airframe consisted of a wooden skeleton clad with spruce plywood, with a final fabric covering on the wings. A long streamlined nose held the main fuel tanks, with the low-set and fully glazed central two-seat cockpit faired into an unbroken line to the tail. The wings were of a thin cantilever monoplane design for high-speed flight, and as such would require stressed-skin construction to achieve sufficient strength. While other designers were turning to metal to provide this extra strength, de Havilland took the unusual approach of increasing the strength of all-wood construction. De Havilland achieved the skin profile using many thin, shaped pieces set side by side, and then overlaid in the manner of plywood. This was made possible only by the recent development of high-strength synthetic bonding resins and its success took many in the industry by surprise.〔Winter, H.T.; ''Flight today and tomorrow'', 1st Edition, Blackie, ca. 1949, Page 232.〕 The engines were uprated versions of the standard Gipsy Six, being tuned for best performance with a higher compression ratio. The DH.88 could maintain altitude up to on one engine. The propellers were two-position variable pitch, manually set to fine before takeoff using a bicycle pump and changed automatically to coarse by a pressure sensor. The main undercarriage retracted upwards and backwards into the engine nacelles, while the tailskid did not retract. Later examples and rebuilds would feature a castoring tail wheel. Landing flaps were placed slightly forward of the inboard wing trailing edge and continued in to the aircraft centre line. The forward fuselage was occupied by two large fuel tanks, with a third small tank located behind the cockpit. With de Havilland managing to meet the challenging production schedule, testing of the DH.88 began six weeks before the start date of the race. In 1935, de Havilland proposed a high-speed bomber version of the DH.88 to the RAF, but the proposal was rejected. 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「De Havilland DH.88」の詳細全文を読む スポンサード リンク
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