[Graham Boak]

Jukka, the Twin Wasp and the Hercules were both used to power the Wellington, and were also considered as alternative types for a number of other aircraft projects. The Twin Wasp sucessfully replaced the temperamental sleeve-valve Taurus on the Beaufort. The Hercules was not a 1600hp engine when it entered service on the Beaufighter and Stirling in 1940, whatever it may have been providing in 1944, and the Twin Wasp was providing considerably more than 1000hp (or 1200hp) on the B-24. The R-2800 and the Centaurus were both used to power the Warwick.

No the Twin Wasp wasn't as powerful as the Hercules was in the end, I never suggested it was, nor the R-2800 as the Centaurus (eventually). But they were in 1940 and 1943, when the powerful British radials were needed in huge numbers and not there. My argument, such as it may be, has always been aimed at the needs of the wartime years, not comparing the worst of certain US engines with non-contemporary best of certain British.

I think this corresponence has exhausted its usefulness.