The Merlin, a liquid cooled, 27 litre, V-12, piston aviation engine, was part of a range of developing engines produced by the world renowned company, Rolls Royce, and during the war over 150,000 engines were to be built.
Rolls-Royce had been developing engines since the turn of the twentieth century, and named the engines after birds, the Kestral, the Buzzard, the Peregrine and the Vulture.
In 1932, Rolls-Royce decided to replace the highly successful Kestral, and started developing the PV-12 engine (PV standing for Private Venture having no Government financing), later to be renamed Merlin.
Early models of the Merlin A – F had many problems, and it was not until the model G was built, that a reliable engine was produce, being named the Merlin II, and was installed in the Supermarine Spitfire.
Up until 1935, the Merlin II had problems with its’ supercharger, sometimes meaning that the engine would cut-out in maneuvers in the Spitfire, and it was replaced by the Merlin XX, using a modified version of the licensed Farman two-speed/two-stage drive. The engine was also developed into the Merlin 130/131 for the De Haviland Hornet and the 133/134 for the Sea Hornet.
Development also continued in America on the Merlin by the Packard Motor Company of Detroit, the V-1650-1, replacing the Allison turbocharged engine of the P-40F’s, which had limiting altitude problems and production demands. This engine was to also power the P-51 Mustangs, giving it the ability to perform well up to 41,900 feet and achieving the speed of 437mph. Over 56,000 engines were produced by Packard Company.
In Britain, the mighty Merlin, was powering the Hawker Hurricane, the Avro Lancaster, Mosquito, and Spitfire. The engine was under constant development, doubling in power from 746 kW (1000 hp) in 1939 to over 1567 kW (2100 hp) by 1944, mostly through improvements in supercharging.
The Merlin was also developed into an engine for tanks the Rolls-Royce Meteor and the Rolls-Royce Meteorite, and for the navy for use in motor torpedo boats and air sea rescue boats.
A Merlin 500/45 engine was used in the Spanish Hispano Aviacion HA 1112MIL Buchon, based on the Messerschmitt Bf 109g-2.
The Rolls Royce Merlin engine in a Supermarine SpitfireThe Rolls Royce Merlin in a Spitfire
The Rolls Royce Merlin engine, The Imperial War Museum, RAF Duxford.
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