Rolls-Royce Merlin Rolls-Royce Merlin The Rolls-Royce Merlin is a British liquid-cooled V-12 piston aero engine of 27-litres (1,650 cu in) capacity. Rolls-Royce designed the engine and first ran it in 1933 as a private venture. Initially known as the PV-12, it was later called "Merlin" following the company convention of naming its piston aero engines after birds of prey. 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, Hawker Hurricane and Supermarine Spitfire. The Merlin remains most closely associated with the Spitfire and
Rolls-Royce/SNECMA M45H The engine had a low turbine entry temperature and comparatively low rotational speed. The engine was designed to be uprated without drastic redesign. Three options were water injection (+10% thrust), improved HP turbine (+10% thrust), addition of a zero-stage to the LP compressor (+25% thrust). The engine was developed at the time of the Rolls-Royce bankruptcy which resulted in delays in developing the engine. A Rolls-Royce/SNECMA M45H engine is on display as part of the aero engine collection at the Royal Air Force Museum Cosford. Rolls-Royce/SNECMA M45H The Rolls-Royce/SNECMA M45H was a medium bypass ratio turbofan produced specifically for the