Although later marks of Supermarine’s most famous fighter, the Spitfire, were themselves far different than the prototype, the ultimate development of the line was in all real ways a virtually new aircraft. By 1943, the performance virtues of laminar-flow wings was well-known; such a configuration placed the thickest part of the wing cross section further back, thus cutting drag. There was interest in developing a laminar wing version of the Spitfire, to be built in parallel with conventional models; the intention was to use the same Griffin engine and as many common airframe components as possible, and indeed the prototype Spiteful was a Spitfire Mk. VIII with the new design wing. This began flight testing in June 1944, but later aircraft would be significantly different, incorporating a new fuselage, larger tail, and repositioned cockpit.
The F. Mk.14, powered by a Griffon 69 rated at 2,375hp, was intended to pave the way for production models, but the first example of this mark did not fly until April 1945, far too late for any use against the Luftwaffe. The F. Mk. 15 could be fitted with either a Griffon 89 or 90, driving counter-rotating propellers, but only one was built, ending up as the prototype for the Seafang naval version.
One Mk. 14 was rebuilt as the Mk. 16 with a supercharged Griffon 101 engine, and in this configuration achieved a top speed of 496mph, faster than any British propeller driven aircraft had flown before or since. Despite this record, the Spiteful’s story was essentially over. Production aircraft would not have been substantially better performers than late model Spitfires, and in any case the Meteor and Vampire jets were making any mark of piston fighter obsolete. Early plans had called for the procurement of 650 Spitefuls, but this figure was steadily reduced as the program lost its priority, and in the end only 19 production aircraft had been completed by the time that the plug was pulled in late 1946.