One of the most successful aircraft engines of the World War II era, 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. 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), and the very latest version as used in the de Havilland Hornet over 2,000 horsepower (1,500 kW). A series of rapidly-applied developments, brought about by wartime needs, markedly improved the engine's performance and durability. The Merlin remains most closely associated with the Spitfire and Hurricane, although the majority of the production run was for the four-engined Avro Lancaster heavy bomber. The first operational aircraft to enter service using the Merlin were the Fairey Battle, Hawker Hurricane and Supermarine Spitfire. Initially known as the PV-12, it was later called Merlin following the company convention of naming its four-stroke piston aero engines after birds of prey.Īfter several modifications, the first production variants of the PV-12 were completed in 1936. Rolls-Royce designed the engine and first ran it in 1933 as a private venture.

The Rolls-Royce Merlin is a British liquid-cooled V-12 piston aero engine of 27- litres (1,650 cu in) capacity.

Liquid-cooled V-12 four-stroke piston aero engine For the Packard-produced licensed version, see Packard V-1650 Merlin.

1000 horsepower military tank engine