Probably the only aero engine to be widely known by name, the Merlin was one of a series of Rolls-Royce engines named after birds of prey. Rolls Royce began making aero engines during World War I at the government's request. During the Battle of Britain it was used to power both of the defending fighters, Hurricanes and Spitfires. The Spitfire was integral to Britain's front-line air defence during World War II together with the Hawker Hurricane fighter.
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