Rolls-Royce R engine was invaluable in the subsequent development of the Rolls-Royce Merlin engine and the Spitfire. A de-rated R engine, known as the Griffon, was tested in 1933, but it was not directly related to the production Rolls-Royce Griffon of 1939, of the same exact bore/stroke and resultant displacement figures as the "R" design. Three examples of the R engine are on public display in British museums as of 2014. Rolls-Royce realised that the Napier Lion engine used in the 1927 Supermarine S.5 Schneider Trophy winner had reached the peak of its development, and that for Britain's entrant in the next
Rolls-Royce Derwent Rolls-Royce Derwent The Rolls-Royce RB.37 Derwent is a 1940s British centrifugal compressor turbojet engine, the second Rolls-Royce jet engine to enter production. Essentially an improved version of the Rolls-Royce Welland, itself a renamed version of Frank Whittle's Power Jets W.2B, Rolls inherited the Derwent design from Rover when they took over their jet engine development in 1943. Performance over the Welland was somewhat increased and reliability dramatically improved, making the Derwent the chosen engine for the Gloster Meteor and many other post-World War II British jet designs. When Rover was selected for production of Whittle's designs in 1941 they set