The Supermarine Spiteful was a British Rolls-Royce Griffon-engined fighter aircraft designed by Supermarine to Air Ministry specification F.1/43 during the Second World War as a successor to the Spitfire. It had a new wing design to improve its critical Mach number, and allow safe operations at higher speeds. The new design also had a modern inwards-retracting undercarriage. Other changes included a larger fin to improve the somewhat marginal stability of Griffon Spitfires and changes to the mounting of the engine to tilt it down slightly for better visibility over the nose.