Rolls-Royce Welland

The Rolls-Royce RB.23 Welland was Britain's first production jet engine. It was designed by Frank Whittle's team at Power Jets, originally intended to be produced by Rover as the W.2B/23. Rover's continued delays in starting production, and Whittle's increasing anger over their failure, led to the project being moved to Rolls-Royce where Stanley Hooker joined the team from Rolls' supercharger division.

The engine was renamed the Welland after the English river, and entered production in 1943 for use on the Gloster Meteor. It was beaten into the air only slightly by the Junkers Jumo 004. Unlike the 004, however, the Welland was a reliable and generally safe engine, due largely to Britain's better metallurgy and Rolls-Royce's considerable experience in the related field of superchargers.

Design and development

The W.2 was basically a larger version of Whittle's original flying design, the Whittle Supercharger Type W.1, or simply W.1, which flew in 1941 in the Gloster E. 28/39 experimental testbed aircraft. The engines used a single double-sided centrifugal compressor, or impeller, with the compressed air being taken off at several ports around the extreme outer edge of the compressor disk. They both used Whittle's "reverse flow" design, in which the flame cans were placed around the turbine to produce a shorter engine. This required the heated air to flow forward before entering the turbine area, which consisted of a single turbine fan. For the W.2, the impeller was 19 inches (480 mm) in size, and powered by 10 flame cans. Air was bled from the compressor and fed into the inner portion of the turbine for cooling. The entire engine weighed about 850 pounds (390 kilograms).

Problems and first flight test

The first examples produced by Rover had serious problems with "surging", in which the speed of the engine would suddenly increase out of control. Maurice Wilks eventually delivered a solution, by adding a set of 20-vane diffusers to the exhaust area. This solved the surging, but they now found that they had serious problems with the turbines failing, due to heat. J.P. Herriot of the Air Inspection Department (A.I.D.) was sent to Rover to provide improved turbine materials, and soon the engine achieved a 25-hour test at 1,250 lbf (5.6 kN) in November 1942. Meanwhile, the prototype Gloster F.9/40, soon to be known as the Meteor, was ready for flight, although the engines were not. Taxi tests were started by test pilot Jerry Sayer on 10 July, 1940 while the flight-quality engines waited. A real flight-test of the engine itself took place on 9 August, 1942, attached to a Vickers Wellington bomber.

Merger of Rover with Rolls-Royce

Whittle was constantly frustrated by Rover's inability to deliver production-quality parts, and became increasingly vocal about his complaints. Whittle accused Rover of "tampering" with the design of the engine—about which Rover knew very little—in order to avoid patent fees and enable Rover to claim the design as their own, whilst Rover's development work was proceeding at a slow pace. Rover was losing interest in the project after the delays and constant harassment from Whittle. Earlier, in 1940, Stanley Hooker of Rolls-Royce had met Whittle, and later introduced him to Rolls' CEO, Ernest Hives. Rolls had a fully developed supercharger division, which Hooker directed, which was naturally suited to jet engine work. Hives agreed to supply key parts to help the project along. Eventually, in early 1943, Spencer Wilks of Rover met Hives and Hooker, and decided to trade the jet factory at Barnoldswick for Rolls' tank engine factory in Nottingham. A handshake sealed the deal.

Rover handed over a total of 32 W.2B/23 engines to Rolls-Royce as well as four “straight-through” W.2B/26 engines, developed by Adrian Lombard. Rolls named their engines, and the continuous flow of air through the jets inspired Hooker to name them after the flow of British rivers. The W.2B/23 became the RB.23 Welland (RB standing for Rolls Barnoldswick), and the W.2B/26 became the RB.26 Derwent. Stanley Hooker took over the task of ironing out the remaining problems, and things soon improved. A flight-quality /23 was fitted to a Gloster G.40, an updated version of the E.28 that had flown the W.1, and was flown by John Grierson on 1 March, 1943. Starting in April, the ratings had been improved to 1,526 lbf (6.79 kN) thrust, and passed a run at 1,600 lbf (7.1 kN) on 7 May, 1943. The prototype F.9/40 was finally fitted with 1,700 lbf (7.6 kN) engines and was flown by Michael Daunt on 24 July, 1943.

Meteor testing

Two Wellands were installed in the first production Meteor Mk.1, EE210/G, (the "/G" signifying "Guard", meaning that the aircraft was to have an armed guard at all times while on the ground) which was test flown by Daunt on January 12, 1944. This Meteor was then sent to the US in exchange for a General Electric J31 (Power Jets W.1) powered Bell XP-59A Airacomet, RG362/G. The Meteor was first flown at Muroc Army Airfield by John Grierson on April 15. Several test flights followed, and by December it had been shipped back to the UK. Production of the Meteor continued, with EF211 to 229 and 230 through 244 entering service No. 616 Squadron RAF in May 1944. The Wellands were rated at 1,600 lbf (7.1 kN), with 180 hours between overhauls. The Jumo 004B, which entering service only a few weeks earlier, was rated at 1,984 lbf (8.8 kN), but required overhaul after 10-20 hours. Flying from RAF Manston, near the English Channel, the 616 first saw action against the V-1 flying bombs en-route to London on July 27, 1944.

Production

From October 1943 a total of 167 Wellands were dispatched from the Rolls-Royce facility at Barnoldswick. By this point, Lombard's straight-through design, the Derwent, had proved to be both more reliable and somewhat more powerful, and production of the Welland ended.

See also

• List of aircraft engines

References

Bibliography

• Jane's Fighting Aircraft of World War II. London. Studio Editions Ltd, 1989. ISBN 0-517-67964-7

External links

• The Welland at enginehistory.org