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 V8 engine of work under Les Maddock and Colin Weston, the first result of which was the N80, a 4-valve, double overhead camshaft, 5.0 litre V8. This successfully ran first stage 1000 hours testing straight off the drawing board without incident. Subsequently, the marketing brief foresaw the requirement for a higher capacity version and the N81, 6.0 litre version, was designed. The project was stopped around 1991 with further development of the L410 engine that enabled emissions requirements to be met using a pre-catalyst assembly at substantially lower investment. Rolls-Royce V8 engine In the history of Rolls-Royce automobiles, only two distinct series