The Supermarine Spitfire is a British single-seat fighter that was used by the Royal Air Force and other Allied countries before, during, and after World War II. The legend born in 1936 as the brainchild of designer RJ Mitchell.
Unlike the early Spitfires which are combined three-bladed engines, later models should have been more powerful because of Messerschmitt Bf 109’s superior high altitude performance. The next generation Spitfires could fly well over 400mph in level flight, thanks to their powerful Rolls-Royce Merlin engine and the four-bladed propeller that helped generate extra thrust. Photo reconnaissance versions you also known them as spy planes were even faster, flying without the dragging weight of machines guns or ammunition.
While fighter Spitfires were defending the skies of Britain, their naked equivalents superlative performance also made it a natural for test flights, especially for high-speed research.
According to famed test pilot Eric ‘Winkle’ Brown’s book Wings on My Sleeve, the high-speed trials began in late 1943. During the programme, Squadron Leader J R Tobin took a Mark XI Spitfire into a 45-degree dive; the plane reached a top speed of 606mph (975km/h), or Mach 0.89. It was the fastest speed a Spitfire had ever flown – or at least the fastest that a pilot had lived to tell the tale. But a far more dramatic flight was soon to take place.
In April 1944, Squadron Leader Anthony F Martindale, put the exact same Mark XI Spitfire into a dive. This time, the reduction gear designed to limit its speed failed. The propeller ripped off and the diving aircraft reached more than 620mph (1,000km/h) – Mach 0.92 – as it plunged towards the ground.
Martindale was saved by simple physics. With the heavy propellers wrenched off, the aircraft was now tail-heavy, and this change in the centre of gravity forced it to climb up from the dive at great speed. Martindale was knocked unconscious from the stress of the climb, and woke to find his aircraft flying at 40,000ft (13 kilometres). Somehow he managed to glide the aircraft back to his base, and emerged unscathed. The stress of the plane’s dive had bent the wings, giving them a slightly swept shape – the kind of shape that would eventually help other aircraft travel through the sound barrier.