Rolls-Royce R revolutions. Although not directly related to the Spitfire, the Supermarine engineers gained valuable experience of high-speed flight with the S.5 and S.6 aircraft, their next project being the Rolls-Royce Goshawk-powered Supermarine Type 224 prototype fighter aircraft. Technological advances used in the R engine, such as sodium-cooled valves and spark plugs able to operate under high boost pressures, were incorporated into the Rolls-Royce Merlin design. The author Steve Holter sums up the design of the Rolls-Royce R with these words: The Schneider Trophy was a prestigious annual prize competition for seaplanes that was first held in 1913. The 1926 race was
Rolls-Royce Crecy the Ricardo E65 engine achieved the equivalent of for the complete engine. By June 1945 a total of 1,060 hours had been run on the V12 engines with a further 8,600 hours of testing on the V-twins. The fate of the six Crecy engines remains unknown. The Crecy proved a unique exercise and Rolls-Royce did not develop any other two-stroke aero engines, the whole concept of advanced piston engines at that time being overtaken by the advent of the practical jet engine. In the Summer of 1941 Supermarine Spitfire Mk II "P7674" was delivered to Hucknall and fitted with a