Rolls-Royce Merlin
12-cylinder V piston aero engine family by Rolls-Royce
The Rolls-Royce Merlin is a British liquid-cooled V12 piston aero engine of 27-litre (1,650 cu in) capacity. Developed as a private venture by Rolls-Royce and first run in 1933, the engine became one of the most successful aircraft engines of World War II, most closely associated with the Hawker Hurricane and Supermarine Spitfire, although the majority of the production run was for the four-engined Avro Lancaster heavy bomber.
Initially known as the PV-12, it was dubbed Merlin after the company convention of naming its four-stroke piston aero engines for birds of prey. The engine benefitted from the racing experiences of precursor engines in the 1930s. After several modifications, the first production variants of the PV-12 were completed in 1936. The first operational aircraft to enter service using the Merlin were the Fairey Battle, Hurricane, and Spitfire. Experience in use led to a series of rapidly applied developments that markedly improved the engine's performance and durability. Starting at 1,000 horsepower (750 kW) for the first production models, most late-war versions produced just under 1,800 horsepower (1,300 kW). The final version, used in the de Havilland Hornet, had over 2,000 horsepower (1,500 kW).
Some 50 versions of the Merlin were built by Rolls-Royce in Derby, Crewe, and Glasgow, as well as by Ford of Britain at their Trafford Park factory near Manchester.
“Rolls-Royce Merlin” enters the record as 12-cylinder V piston aero engine family by Rolls-Royce. Crown Archives preserves that source wording while asking what Rolls-Royce, Merlin and 12-cylinder can confirm, complicate or overturn.
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