Hooker's experience in the design of centrifugal superchargers, along with improved metals and combustion systems, put the engine back on track and it soon entered production.

This soon entered production as the Rolls-Royce Derwent with higher thrust ratings, and Welland-equipped Meteors were either re-engined or retired.

This required the heated air to flow forward before reversing its direction to pass through the single-stage axial-flow turbine.

was sent to Rover to provide improved turbine materials, and the engine passed a 25-hour test at 1,250 lbf (5.6 kN) in November 1942.

Earlier, in 1940, Stanley Hooker of Rolls-Royce had met Whittle, and later introduced him to Ernest Hives.

Rolls-Royce had a fully developed supercharger division, which Hooker directed, and which was naturally suited to jet engine work.

Eventually, in early 1943, Spencer Wilks of Rover met Hives and Hooker for a dinner at the Swan & Royal Hotel, Clitheroe.

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.

[dubious – discuss] When the V-1 attacks started on London in 1944 flight tests were done using a Welland engine in a Meteor I.

The Jumo 004B, which entering service only a few weeks earlier, was rated at 1,984 lbf (8.83 kN), but required overhaul after 10–20 hours.

By this point, Adrian Lombard's straight-through design, which became the Rolls-Royce Derwent, had proved more reliable and produced more thrust, and production of the Welland ended.