Supermarine Spitfire

The Spitfire grew out of the work of R. J. Mitchell, chief designer at Supermarine Aviation Works, a Vickers-Armstrong subsidiary, whose reputation rested on the racing seaplanes with which Britain dominated the Schneider Trophy. His first modern fighter, the Type 224 submitted to specification F.7/30, flew in February 1934 and disappointed: open cockpit, fixed undercarriage and a 600 hp Rolls-Royce Goshawk that failed to deliver. Mitchell pressed on as a private venture with a new design, the Type 300, with retractable undercarriage, reduced span and the PV-12 engine later named the Merlin; the Air Ministry backed it in December 1934 and wrote specification F.37/34 around it.

What made the aeroplane unmistakable was the elliptical wing drawn by the aerodynamicist Beverley Shenstone: not a stylistic flourish but the shape that allowed the thinnest possible section while leaving room inside for the undercarriage, the guns and their ammunition. The prototype K5054 lifted off from Eastleigh on 5 March 1936 with Joseph 'Mutt' Summers, Vickers' chief test pilot, at the controls, in a flight of barely eight minutes. Specification F.10/35 had meanwhile settled on eight machine guns, and in June 1936 the Air Ministry ordered 310 aircraft.

Building that wing proved far harder than drawing it, and deliveries slipped. The first production Spitfire left Woolston in mid-1938 and on 4 August the RAF took delivery at Duxford for No. 19 Squadron; when war broke out only nine squadrons were equipped. Mitchell never saw it in action: he died of cancer in 1937, and his colleague Joseph Smith took over as chief designer, shepherding every mark through to the 24.

In the Battle of Britain the Hurricane was more numerous and flew more sorties, but the Spitfire suffered lower attrition and achieved a better ratio of victories to losses; it was held back for the Messerschmitt Bf 109E while the Hurricanes went for the bombers. The Luftwaffe struck at the source: on 26 September 1940 it destroyed the Woolston factories, killing 92 people, and production had to be scattered across workshops and garages in southern England. Castle Bromwich, in Birmingham, became the programme's industrial heart and delivered 12,129 aircraft.

The adaptability of the airframe explains the aeroplane's long career. From the Mk I, 1,567 of them with a 1,030 hp Merlin, came the Mk V with its 1,470 hp Merlin 45, the most numerous mark of all. The arrival of the Focke-Wulf Fw 190 in 1941 left the Mk V outclassed and forced a stopgap that turned out brilliantly: the Mk IX, with a two-stage supercharged Merlin, restored parity and passed 650 km/h. The wings were also offered in four armament layouts — A, B, C and E — mixing 7.7 mm machine guns with 20 mm Hispano cannon.

The next step was the larger Rolls-Royce Griffon: the Mk XII introduced it and the Mk XIV exploited it fully, its 2,050 hp Griffon 65 giving 722 km/h (449 mph). The final marks, F.21, F.22 and F.24, pushed the formula as far as the airframe would allow. The last Spitfire left the factory in February 1948: 20,351 of all variants had been built since 1938.

The photographic reconnaissance versions deserve a chapter of their own, stripped of guns and lightened to fly high, far and unescorted: they photographed the German Freya and Würzburg radars in 1941 and 1942 and in 1943 confirmed over Peenemünde the German retaliation-weapons programme. The Royal Navy, for its part, adapted the fighter for carriers as the Seafire, of which 2,646 were built; it fought in Operation Torch, at Salerno, in the Pacific against Japanese suicide attacks and still in Korea in 1950, despite a narrow undercarriage and poor forward visibility that made it awkward on deck.

The last operational sortie by an RAF Spitfire was flown by a PR Mk 19 of No. 81 Squadron on 1 April 1954 from Seletar, over Johore, during the Malayan Emergency. The type's last RAF flight, by then with no military role, took place on 9 June 1957 at Woodvale. Ireland kept its own until 1961, and around sixty airframes remain airworthy today.