The Griffon Engine was designed by upscaling the Merlin to meet the power requirements asked for by the RAF in 1941, which found the Spitfire lacking in combat with the Fw-190. This Griffon 61 produced 1730 horsepower at up to 21,000 feet.
Spitfire Mark IV Griffon prototype serial number DP845 in flight. Thsi plane first flew on November 27, 1941, and was later designated the Mark XX. With 24 major variants of the Spitfire, the RAF eventually gave up and used regular numbers instead of Roman numerals.
RJ Mitchell. A life in Aviation. Spitfire and Battle of Britain. RJ Mitchell managed Supermarine which built the Battle of Britain Spitfire, flying boats and Schneider Trophy winning aircraft. RJ Mitchell is remembered for the Spitfire and Schneider Trophy.