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 Motor Cars most likely buyer was BMW, which already supplied engines and other components for Rolls-Royce and Bentley cars, but BMW's final offer of £340 million was beaten by Volkswagen's £430 million. A stipulation in the ownership documents of Rolls-Royce dictated that Rolls-Royce plc, the aero-engine maker, would retain certain essential trademarks, including the Rolls-Royce name and logo if the automotive division was sold. Although Vickers plc sold the vehicle designs, nameplates, administrative headquarters, production facilities, Spirit of Ecstasy and Rolls-Royce grille shape trademarks to Volkswagen AG, Rolls-Royce plc chose to license the Rolls-Royce name and logo to BMW AG for £40