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 Holdings 2007 that production of the Trent 900 had been restarted after a twelve-month suspension caused by delays to the A380. On the military side, Rolls-Royce, in co-operation with other European manufacturers, has been a major contractor for the RB199 which in several variants powers the Panavia Tornado, and also for the EJ200 engine for the Eurofighter Typhoon. Two modified RB199 engines also powered the EAP demonstrator which evolved into the Typhoon. Rolls-Royce has matured the Rolls-Royce LiftSystem invented by Lockheed Martin for the Joint Strike Fighter (JSF) F-35 Lightning II to production level, planned to be produced in significant numbers.