The Nene or RB.41, was Rolls-Royce's third jet engine to enter production, designed and built in an astonishingly short five month period in 1944, first running on October 27th, 1944. The design saw little use in English designs, being passed over in favour of the Avon that followed it. It's only widespread use in England was in Hawker Sea Hawk and the Supermarine Attacker. Pratt and Whitney took out a license on the Nene, which went on to power many of their early carrier-based aircraft, notably the famous Grumman F9F Panther. Twenty-five were given to the Soviet Union as a gesture of goodwill, and were used to develop the Klimov RD-45 , and a larger version, the Klimov VK-1 , which were soon appearing in various Soviet fighters.

Although based on the "straight-through" version of the basic Whittle-style layout, the Nene used a double-sided centrifugal compressor for improved compression ratio and thus higher thrust. It had nine combustion chambers and a single turbine stage and weighed 750 kg. It was during the design of the Nene that Rolls decided to give their engines numbers as well as names, with the Welland and Derwent keeping their original Rover models, B/23 and B/26. It was later decided that these model numbers looked too much like those for bombers, and "R" was added to the front, the "R" signifying "Rolls" and the original Rover "B" signifying Barnoldswick. This "RB" designation scheme continues to this day.

The Nene doubled the thrust of the earlier generation engines, with early versions providing about 5,000 lbf (22 kN), but remained generally similar in most ways. This should have suggested that it would be widely used in various designs, but the Gloster Meteor proved so successful that the Air Ministry felt there was no pressing need to improve upon it. Instead a series of much more capable designs using the Avon were studied, and the Nene generally languished.

References

• The Nanton Lancaster Society