The Supermarine Spiteful was developed to replace the Spitfire, but by the time it was ready to enter service it was no longer needed, and only a handful were ever completed.
Work on the Spiteful began surprising early, with Supermarine Specification 469 of September 1942 which called for a single seat high performance fighter. At this point the plan was to use a modified Spitfire F.Mk.21 with a Griffon engine.
The most important development for the Spiteful was a new laminar flow wing, which had the thickest section located further back than was normal. This was designed to Supermarine's own Specification 470 of 30 November 1942, which called for a wing that would reduce drag, increase the speed at which compressibility began to cause problems (this occurred close to the speed of sound), and to give a high rate of role. The new wing was given the Supermarine Type No.371. The new wing design was tested at the National Physical Laboratory. The resulting wing was very clearly different from the familiar Spitfire wing. It had straight leading and trailing edges, and tapered towards the tip. It was also significantly smaller and lighter than the wing used on the Spitfire Mk.21, and was expected to produce an increase in speed of 55mph.
In February 1943 the Air Ministry issued Specification F.1/43 to allow Supermarine to develop the new fighter. At this stage it was to use the new wing and a fuselage based on the Spitfire Mk.VIII, and the wing was to be made with folding in mind so it could be used with the Navy.
At this stage four prototypes were planned. The first would use a Mk XIV fuselage and the new wing. The second would use a new fuselage and a contra-rotating Griffon engine. The third would use a Merlin engine. The fourth was for the Navy.
Wind tunnel tests showed that the contra rotating propeller caused stability problems. As a result the Spiteful got a larger fin and rudder.
On 1 March 1944 the Air Ministry inspected a mock-up of the new design. The name Spiteful was suggested by Vickers on 4 March.
The first prototype was delayed by problems with the wing. It was finally ready in April 1944, and was installed onto Mk XIV NN660. This prototype, powered by a Griffon 61, made its maiden flight on 30 April 1944 with Jeffrey Quill at the controls. Unfortunately it was destroyed in a fatal crash on 13 September.
Work on the second prototype was suspended after the fatal crash, and it didn't make its maiden flight until 8 January 1945.
Work on the third, Merlin powered, prototype, was cancelled in March 1944.
The fourth prototype, RT464, was never completed and was used for structural tests.
The Spiteful had a fuselage very similar to the late model Spitfires, with a bubble cockpit canopy. The wings tapered slightly in the centre, then more steeply outside the undercarriage. The tail resembled the familiar Spitfire model.
The Spiteful prototype made its maiden flight on 30 June 1944.
Despite all of the development work the Spiteful was disappointing. In flight it suffered from aileron snatching, and had problems close to the stall. However the laminar flow wing did perform quite well. The first and second prototypes suffered from instability in the air and needed larger funs, rudders and tailplanes.
The first production Spiteful, F.Mk.14 RB515, made its maiden flight on 2 April 1945. This was built with the standard Spitfire F.Mk 21 tail, but during repairs at Boscombe Down was given the enlarged fin and rudder. The machine was damaged again in September 1945.
A third prototype, NN667, with a longer carburettor intake, made its maiden flight on 27 March 1946, but by this point the Air Ministry was no longer interested in the Spiteful.
At first Supermarine received contracts for 650 Spitefuls. As time went on the numbers were reduced – first to 390, then to 80 and then to 22. On 16 December 1946 this was reduced once again, to only seventeen.
Only 19 Spitefuls were completed (RB515-525, RB527-531 and RB533-535), and they didn’t enter squadron service. Instead they were used for further work on the laminar flow wing, in preparation for the upcoming jet aircraft. During these trials the Spiteful reached 494mph.
Three versions of the Spiteful were designed.
The Spiteful F.Mk 14 used a 2,375hp Griffon 65 and had a top speed of 475mph. This was the main production version and visually resembled a late production Spitfire, but with the new style of wing.
The Spiteful F.Mk 15 would have used a Griffon 85 and had contra rotating airscrews. One was built.
One Spiteful F.Mk 16 was produced by converting a Mk 14 (RB518). This had a Griffon 101 engine, and a five blade Rotol propeller when first built and was used to test the engine. It was damaged during tests on 6 February 1946 and rebuilt with a Griffon 121 engine and a six blade Rotol contra-rotating propeller. The Mk.16 reached a top speed of 494mph.
The Spiteful was also produced in a naval version, as the Supermarine Seafang, but this did no better than the Spiteful.
Spiteful F.Mk 14
Engine: Griffon 69
Span: 35ft 6in
Length: 32ft 8in
Empty weight: 7,350lb
Loaded weight: 10,200lb
Max speed: 483mpg at 21,000ft
Service ceiling: 42,000ft
Armament: Four 20mm Hispano Mk V cannon
Bomb load: two 1000lb bombs or two 300lb rockets