Rolls-Royce Limited increase its own production rates. By the late 1920s, aero engines made up most of Rolls-Royce's business. Henry Royce's last design was the Merlin aero engine, which was first flown in prototype form in 1935, although he had died in 1933. This was developed from the R engine, which had powered a record-breaking Supermarine S.6B seaplane to almost in the 1931 Schneider Trophy. The Merlin was a powerful supercharged V12 engine and was fitted into many World War II aircraft: the British Hawker Hurricane, Supermarine Spitfire, de Havilland Mosquito (twin-engine), Avro Lancaster (four-engine) (a development of the Avro Manchester with
Rolls-Royce WR-21 Rolls-Royce WR-21 The Rolls-Royce WR-21 is an advanced gas turbine marine engine, designed with a view to powering the latest naval surface combatants of the partner nations, and currently fitted to the Type 45 destroyer of the Royal Navy. Developed with government funding input from the UK, France and the United States, the WR-21 was designed and manufactured by an international consortium led by Northrop Grumman as prime contractor. The turbine itself was designed primarily by Rolls-Royce with significant marine engineering and test facility input from DCN, with Northrop Grumman responsible for the intercooler, the recuperator and system integration. WR-21