Supermarine Spitfire PR Mk XIX

The PR Mk XIX solved high-altitude reconnaissance by combining two lineages: the Mk XI's D-type wing, whose entire leading edge ahead of the spar became a fuel tank, and the Mk XIV's Griffon. The first aircraft, type 389s, were built without a pressure cabin; early in production the pressurised cockpit developed for the Mk X was adopted and the aircraft became the type 390. Fuel capacity reached 256 gallons, three and a half times that of the original Spitfire, because the Griffon drank far more than the Merlin and without that reserve the endurance would have made the aeroplane useless.

A PR Mk XIX carried no guns at all. Its defence was height, speed and not being seen. It worked above the practical reach of enemy fighters, with vertical and oblique cameras in the rear fuselage, and came home with the only payload that mattered: exposed film. The first aircraft entered service in May 1944 and within months had all but replaced the Mk XI. A total of 225 were built before production ceased in early 1946.

No other Spitfire variant lasted as long in RAF hands. PR 19s flew over Palestine and Malaya, and in 1951, at the request of US naval intelligence, over Hainan Island from Kai Tak in Hong Kong. The last operational sortie by an RAF Spitfire was flown by a PR 19, PS888 of 81 Squadron, on 1 April 1954 out of Seletar, photographing jungle in Johore with the words 'The Last' painted on its nose by the ground crew. The final non-operational RAF flight of the type, on 9 June 1957, was also a PR 19, and it closed the story of the piston fighter in the service.

In 1962 and 1963 a PR 19 flew official sorties once more, this time as the adversary: the RAF matched it against an English Electric Lightning to work out how a supersonic jet should attack a propeller fighter, with Indonesian Mustangs over Borneo in mind. The trials concluded that infra-red missiles struggled to lock onto so cool an exhaust and that the only sensible tactic was to come from below in a single fast pass. Abroad, the Swedish Air Force equipped its F 11 reconnaissance wing with fifty aircraft designated S 31, which in the late 1940s overflew Soviet airspace at heights no fighter could reach.