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"Back on track here I think the Napier Sabre was the most advanced piston engine to see service in WW2, but I think that, on the whole, the US companies Pratt & Whitney Aircraft and Curtiss-Wright designed the best large engines."
The Napier Sabre may have been the most advanced, wither it was worth the time and money spent on it is another matter, since the answer, if it exists, has been buried since WW II. While at least some cost figures for P & W and Wright engines does surface on occasion both the Bristol and Napier sleeve valve R&D costs have remained unknown to the world at large. Somebody may be able to ferret out the cost of post war Bristol engines but since all Napier sales were to the government they may be much harder to find.
The Sabre, for all it's "advancement went exactly nowhere after the war. No commercial sales and darn little use in post war military aircraft except to complete a few existing contracts?
Now I will grant that the majority of post war P & W R-2800s difference from even the war time "C" series engines and that the post war Wright R-3350s also differeed from the majority of wartime R-3350s. Likewise post war Hercules and Centaurus engines differed form war times ones( Hercules went to main bearings with larger rollers for one thing).
AN awful lot of money and time was spent on the Sabre which wound up powering about 4500-4600 airplanes, almost all being single engine.
Napier is a strange case. After WW1 and until 1930 it was the aero engine company that received most money from the Air Ministry, and by a substantial margin, more than the 'other three' (Armstrong Siddeley, Bristol and Rolls Royce) combined in many of the years through the twenties.
The problem for Napier, and the company wasn't alone then and wouldn't be now, was a lack of investment in research and development. Between 1923 and 1930 the company received £5.4 million from its Air Ministry contracts, again more than twice that paid to any of the 'other three', annual profits averaged nearly £200,000 and gilt edged investments just shy of £1 million had been accumulated by 1927.
This was all on the back of the 'Lion' engine which dominated military sales until 1930. Unfortunately, whilst Rolls Royce and Bristol were already developing engines which would become, for example, the 'Kestrel' and 'Pegasus', Napier did absolutely nothing. Having declared higher profits than any other company within the aircraft industry in 1929 it made a loss in 1933.
It is impossible to over estimate the effect of this blase attitude to research and development within British industry. At the height of its prosperity, with money to be invested, Napier was approached by the Air Ministry to develop an engine along the lines of the American Curtiss D-12. The company refused, Rolls Royce took on the work, a D-12 was indeed made available to Rolls Royce at Derby in late 1925 at a time when the team there was under Hives and Rowledge. How much it influenced the Kestrel, the engine which established Rolls Royce as one of Britain's foremost engine manufacturers of the 1930s, can be debated elsewhere. Between 1930 and 1934 Rolls Royce produced 1,182 engines and profits rose from £177,000 to £597,000. Napier nearly went bust.
Had it not been for the looming war it is likely that 'Messrs. Napiers' (as the Air Ministry liked to call the company) would have been allowed to whither and die. By July 1935 the Permanent Under-Secretary, the brilliant Sir Christopher Bullock whose role in establishing the RAF as an independent service is woefully overlooked, was writing that it "was essential that Messrs. Napiers should be kept alive as a separate entity, in order to prevent the engine industry being constituted on too restricted a basis." This sums up government policy towards the firm throughout the immediate pre-war period. It was regarded as an essential cog in a rather larger machine. It was to this end that the initial order for six 'Sabres' was placed in 1937, and in the same year plans for a new Sabre engined fighter to replace the Spitfire and Hurricane were drawn up.
The trials and tribulations of the Sabre are well known, but we shouldn't forget that Rolls Royce and Bristol also struggled with their next generation engines. The Vulture failed consistently in 1939 and the Centaurus....
The decision to gamble on Napier and the Sabre engine was taken on two principle grounds, neither of them financial. The engine would provide a third string to the British bow, should the Vulture and Centaurus fail, and it kept Napier in the aero engine industry. Once the decision was made it started to need financing, the new factory at Liverpool etc.
An overlooked by product of the decision was the effect on Rolls Royce. It gave urgency to Merlin development and indirectly led to the abandonment of the Vulture and development of the Griffon.
Cheers
Steve
Finding out the prices for any big-ticket industrial item is not trivial; P&W, Bristol, and C-W didn't have public price lists. I suspect that the Centaurus and Hercules were more expensive than the corresponding engines from P&WA and C-W, but wouldn't bet more than a few cents (or pence) on it. I also suspect that the big radials weren't much cheaper than the gas turbines that were coming out, at least per horsepower. As a WAG, a post-ww2 production R-2800 or R-3350 would be around $20,000 to $30,000, although I'd not be shocked if that number was off by a factor of 2.
Both companies failing to come up with up to date, truly competitive products in the 1929-34 period to base further developments on put the AIr Ministry in the position of making leaps of faith when placing contracts in the late 30s to keep them in business.
It is not just the cost of the engines, it is the cost of the R&D to bring the engine to production. Granted in the case of the R-2800 there were a number of sets of R&D costs. 1st set is the R&D for the 'A' series engines, 2nd set is the 'B' series, not a very big one. 3rd set is the 'C' series engines where everything was brand new. Continuing R&D on the 'C' series involved new pistons and connecting rods . The rods were lengthened 1 in and the wrist pins moved up in the pistons. Stroke and engine diameter remained the same.
Now the company will try to spread the R&D costs out over the production run of the engines but can't charge too much for the first few hundred (or even first few thousand) without making the engine uncompetitive price-wise.
One source says P& W spent 8 million dollars on the R-2800 but doesn't say what stage that brought them to. I would say either the A or B as the comparison was being made to the Wright R-2160. The P & W R-4360 took 25 million but it used a lot of parts/knowledge from the "C" Series R-2800. dividing 25 million by the 18,687 production run of the R-4360 means each engine built cost over $1300 in RD.
Once you have the design finalized (production ready) you can talk about actual production costs , materials and machine/man hours to make parts and assemble.
aside from very rough estimates the R & D costs and production costs of the sleeve valve engines are unknown to the public.
The Sabre is probably the poster child for why "most advanced" does not necessarily equal "best.""Back on track here I think the Napier Sabre was the most advanced piston engine to see service in WW2, but I think that, on the whole, the US companies Pratt & Whitney Aircraft and Curtiss-Wright designed the best large engines."
The Napier Sabre may have been the most advanced, wither it was worth the time and money spent on it is another matter, since the answer, if it exists, has been buried since WW II. While at least some cost figures for P & W and Wright engines does surface on occasion both the Bristol and Napier sleeve valve R&D costs have remained unknown to the world at large. Somebody may be able to ferret out the cost of post war Bristol engines but since all Napier sales were to the government they may be much harder to find.
The Sabre, for all it's "advancement went exactly nowhere after the war. No commercial sales and darn little use in post war military aircraft except to complete a few existing contracts?
Now I will grant that the majority of post war P & W R-2800s difference from even the war time "C" series engines and that the post war Wright R-3350s also differeed from the majority of wartime R-3350s. Likewise post war Hercules and Centaurus engines differed form war times ones( Hercules went to main bearings with larger rollers for one thing).
AN awful lot of money and time was spent on the Sabre which wound up powering about 4500-4600 airplanes, almost all being single engine.
I found a list of engine prices for Bristol Mercury engines, originally produced to compare the cost of those produced by the parent and those produced by the 'Shadow Industry'.
The cost given is 'average price per engine'.
Bristol:
1st 500, £1,913. 2nd 500, £1,306. 3rd 500 £1,197. The price was reduced by almost 40% over the run of the first 1,500 engines.
Shadow Industry.
1st batch of 987, £1,496. 2nd batch of 887, £1,486. It seems here, where many production issues would already have been solved by Bristol, the price per engine was far more stable. Higher wages in the Midlands, where many of the shadow factories were located, was considered the principle reason that the engines produced there cost slightly more than those at the parent.
£1,500 per engine in 1939 money is equivalent to very approximately £97,000 in today's money.
Cheers
Steve
This is precisely the point I'm making. The Air Ministry made that leap in the case of Napier in 1937. It wasn't just the engine contracts, an entire factory at Liverpool also had to be financed.
With the benefit of hindsight we can safely say that this was a waste of money. Britain would not have lost the war and the Air Ministry/RAF would not have suffered unduly if both Napier and the aero engine division of Armstrong Siddeley had been allowed to fall by the wayside. Whilst it seemed undesirable to concentrate British aero engine production in just two companies, especially before the role of the US in the war was clear, it would not have had the undesirable consequences feared.
Both companies were lazy. Napier was going along very nicely until the late 1920s, trading on ancient engines which a lack of foresight and planning allowed the company to believe would continue into the future. It didn't
Armstrong Siddeley is a slightly different case, the aero engine business being just one under that umbrella. It too was guilty of complacency and lack of foresight.
As a man who once owned several British motorcycles I could argue that this is a recurring theme in some British industries.
Cheers
Steve
I remember reading -- and I don't know how true this is -- that Napier was also struggling with basic quality issues in their manufacturing process.
Was there a royalty payment/licence fee for Bristol from the shadow factories?
I found a list of engine prices for Bristol Mercury engines, originally produced to compare the cost of those produced by the parent and those produced by the 'Shadow Industry'.
The cost given is 'average price per engine'.
Bristol:
1st 500, £1,913. 2nd 500, £1,306. 3rd 500 £1,197. The price was reduced by almost 40% over the run of the first 1,500 engines.
Shadow Industry.
1st batch of 987, £1,496. 2nd batch of 887, £1,486. It seems here, where many production issues would already have been solved by Bristol, the price per engine was far more stable. Higher wages in the Midlands, where many of the shadow factories were located, was considered the principle reason that the engines produced there cost slightly more than those at the parent.
£1,500 per engine in 1939 money is equivalent to very approximately £97,000 in today's money.
Cheers
Steve
As an aside, why did the UK's Air Ministry feel the need for a third first-tier aircraft engine maker?
...
As an aside, why did the UK's Air Ministry feel the need for a third first-tier aircraft engine maker?
Possibly due to fears one well aimed bombing raid could halve engine production.