Ah, I see.

The problem, if it’s real, did affect its future. It made it sluggish at height, and this counted very greatly against continuing with production (I have that in writing), and development – and thus being thought a ‘success’. The Spitfire was different – The Spitfire was a proven aircraft with a development ‘roadmap’ attached by the time the disappointing altitude performance of the MkII (a fast aeroplane, otherwise) came to light. By contrast the Whirlwind hadn’t even been delivered to squadron strength at the time, and the programme was eminently ‘haltable’ – and it was.

It is actually surprisingly difficult to find a precise date on which the Whirlwind was ‘written off’. Thanks to one of our researchers I am now looking at probably the entire record set held by the National Archives on the Whirlwind. The short version of the timeline is that on 8th May 1940, in response to the concern expressed by George Bullman (the Air Ministry’s Engine ‘Head’) about the effect of continued Peregrine production on Rolls’ output, WR Farrar, the AD to the DTD simply said in a memo ‘No New Whirlwinds’. This is as close to an official decision as I can get.

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However, before, during and after this decision was being made there was a discussion carrying on about the Mark II (AVIA15/317). This would have had Morris radiators, 100-octane-ready Peregrines, greater tankage, revised cannon feed arrangements and Hydromatic props, no mention of blade changes, just the greater pitch range imparted by the Hydromatic mechanism.

No decision was made on this until Dowding wrote to Beaverbrook in October 1940 saying (in response to a direct question) that although it was still to early to say for definite he’d not be unhappy if no further Whirlwinds were produced. I doubt very much that Whirlwinds were anywhere near the front of Dowding’s mind at the time.

Beaverbrook replied with characteristic unilateralism (and in line with Alertken’s post above) that he would therefore not produce any more Whirlwinds. It looks like the axe was ultimately wielded by the Minister for Aircraft Production acting independently and without official sanction (beyond a three-word memo five months earlier), but all official parties were happy to tacitly let it go, meaning they could stop thinking about the Whirlwind and focus on other things.

There was a last comment on the matter made at a meeting in February 1941, more a post-rationalisation of the decision made by Beaverbook for the Ministry three months earlier:

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I would still argue that the propeller tip story is not irrelevant, however. It was a limiting factor on the aircraft before any decisions were made, it didn’t just kick in after the event. Decisions were made upon the usefulness of the aircraft as against its impact on production capabilities. Performance at height, or rather the lack of it, figured very largely on the ‘balance sheet’.

I am not claiming a conspiracy as such – it is more an interesting angle, and one that showed where the problem may have been in a purely technical sense.

But it is a fact that compressibility was understood by some at the point in time where the future of the WW was under discussion.. but what went on record was the Peregrines were choking at height. I agree with you, Graham.. the right ‘resources’ – human ones – were not applied, for simple reasons. The decision to move on had already been taken 🙂