Rolls-Royce Merlin exhaust flow and waste-gates, meant that this option was rejected in favour of the two-stage supercharger. Fitted with the two-stage two-speed supercharger, the Merlin 60 series gained 300 horsepower (224 kW) at over the Merlin 45 series, at which altitude a Spitfire IX was nearly faster than a Spitfire V. The two-stage Merlin family was extended in 1943 with the Merlin 66 which had its supercharger geared for increased power ratings at low altitudes, and the Merlin 70 series that were designed to deliver increased power at high altitudes. While the design of the two-stage supercharger forged ahead, Rolls-Royce also
Rolls-Royce Falcon unusual feature of this engine was the epicyclic propeller reduction gear which contained a clutch designed to limit the maximum torque, thus protecting the reduction gears. The Falcon was notably used in the Bristol F.2 Fighter and Blackburn Kangaroo bomber. "Note:" "List from Guttery and Lumsden:" Bristol F.2B Fighter, "D-8096", is based at the Shuttleworth Collection and is powered by a Falcon III, this aircraft flies regularly throughout the summer months. Rolls-Royce Falcon The Rolls-Royce Falcon is an aero engine developed in 1915. It was a smaller version of the Rolls-Royce Eagle, a liquid-cooled V-12 of 867 cu in (14.2