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The Supermarine Spiteful was a British Rolls-Royce Griffon-engined fighter aircraft designed by Supermarine to Air Ministry specification F.1/43 during the Second World War as a successor to the Spitfire. ==Design and development== By 1942, Supermarine designers had realised that the characteristics of the Spitfire's wing at high Mach numbers might become a limiting factor in increasing the aircraft's high-speed performance. The main problem was the aeroelasticity of the Spitfire's wing; at high speeds the relatively light structure behind the strong leading edge torsion box would flex, changing the airflow and limiting the maximum safe diving speed to 480 mph (772 km/h) IAS. If the Spitfire were to be able to fly higher and faster, a radically new wing would be needed.〔Morgan and Shacklady 2000, p. 493.〕 Joseph Smith and the design team were aware of a paper on compressibility, published by A D Young of the R.A.E, in which he described a new type of wing section; the maximum thickness and camber would be much nearer to the mid-chord than conventional airfoils and the nose section of this airfoil would be close to an ellipse. In November 1942 Supermarine issued Specification No 470 which (in part) stated: Specification 470 described how the wing had been designed with a straight taper to simplify production and to achieve a smooth and accurate contour. The wing skins were to be relatively thick, aiding torsional rigidity which was needed for good aileron control at high speeds. Although the prototype was to have a dihedral of 3° it was intended that this would be increased in subsequent aircraft.〔 To improve the ground-handling the Spitfire's narrow-track, outward-retracting undercarriage was replaced with a wider-track, inward-retracting system. (This eliminated a weakness in the original Spitfire design, giving the new plane similar, safer landing characteristics, comparable to the Hurricane, Typhoon, Tempest, Mustang, and Focke-Wulf 190.) The Air Ministry were impressed by the proposal and, in February 1943, issued Specification F.1/43 for a single-seat fighter with a laminar flow wing; there was also to be provision made for a wing folding scheme to meet possible Fleet Air Arm requirements. The new fighter was to use a fuselage based on a Spitfire VIII.〔Morgan and Shacklady 2000, p. 494.〕 The new wing was fitted to a modified Spitfire XIV ''NN660'', in order to make a direct comparison with the earlier elliptical wing, and was first flown on 30 June 1944 by Jeffrey Quill. Although the new Spitfire's speed performance was comfortably in excess of an unmodified Spitfire XIV, the new wing displayed some undesirable behaviour at the stall which, although acceptable, did not come up to the high standards of Mitchell's earlier elliptical wing. ''NN660'' crashed on 13 September 1944, killing pilot Frank Furlong. No reason for the loss was officially established.〔Mason 1992, p. 323.〕 In the meantime, the opportunity had been taken to redesign the Spitfire's fuselage, to improve the pilot's view over the nose and to eliminate gross directional instability by using a larger fin and rudder. This instability had been apparent since the introduction of the more powerful Griffon engine. The instability was exacerbated by the increase in propeller blade area due to the introduction of the four-bladed and subsequent five-bladed Rotol airscrews for the next aircraft, ''NN664'' (for which Specification F.1/43 had been issued). The updated design incorporated the new fuselage (although lacking the enlarged fin/rudder) and, as it was now substantially different from a Spitfire, the aircraft was named "Spiteful" (although "Victor" had been originally proposed). 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「Supermarine Spiteful」の詳細全文を読む スポンサード リンク
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