In
1932, the Air Ministry declined to fund a new engine and Rolls-Royce
decided to develop one using their own funds. Designated the P.V.12
(private venture), this engine first flew in 1935.
Named the Merlin, this engine was made
famous by the Spitfires and Hurricanes that won the Battle
of Britain.
The Rolls-Royce Merlin was license-built by
Packard in the U.S. These Merlins were designated the V-1650.