1940: the top 3 engines in service

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Is this the myth of British Merlins being hand fitted again?

It is my understanding that most British built Merlin components were interchangeable with US built versions. Basically except where there was a design difference, such as the supercharger drive on two stage engines.

Wasn't there even an example where the RAF broke down several Merlins so that the USAAF could use them for spare parts for their P-40F/Ls in Africa?

Life expired RR and Packard engines were broken down to provide parts for Rover built Meteor Tank engines when production outstripped parts supply. Mainly Cranks, Rods and Cylinder blocks. The Packard and RR parts were given the same Rover part number and used interchangeably. Derby engines from the MkXII onwards were sometimes hand fitted but that was because they were built in small batches for special needs or were early production prototypes. Merlin/V1650s from RR Crewe, Fords Manchester, Government engine factory Glasgow and Packards Detroit were interchangeable for all intents and purposes. Fittings and ancillaries might be different between British and US manufacture but all major parts were identical between similar models.

Packard built a small number of types in vast quantities over 3 and a bit years but RR Derby built dozens if not hundreds of different types over 20 years so modern day parts supply can be a problem if using RR parts. A 1955 Merlin 621 crank might not fit a 1936 Merlin G crankcase.
 
Hmm - the XX might be a better choice from the Merlin stable.
The Klimov M-105 might not be in service in 1940? The predecessor, M-103, was a rework of the M-105, that was a license copy of the Hispano Suiza 12Y engine. The M-103 was good for 1000 CV for take off, and 960 CV at 4000 m.
For 1940, the interesting Soviet engine might be the M-88, the upgrade of the G&R 14N engine that was also licensed. Don't know whether the 2-speed upgrade, the M-88B was in service already then, it was making 1100 HP at 4000 m, but also 1000 HP at 6000 m.
The AM-35 was also there (the AM-35A not being available in 1940?), 1200 HP at 5000 m, shortcoming being a bulky heavy engine.
 
After my sources the Jumo 211 reached at 1940, 180 hours service life, before a major revision/overhaul, what is to my opinion a pretty impressiv reliability for this timeline (DB 601 average 80-100 hours), for a V12 water-cooled inline, with 1200PS at 1940.
As it was said, it was not the engine with major innovations, but a very stable and reliable workhorse.
 
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About the interchangeability thing, I have to take the word of Merlin owners on that. I know about 20 and that's what they say. I've seen and helped with some minor Merlin work but none of it required extraordinary parts reworking and none of it was fitting new parts except new main bearings and new rings. You have to hand-scrape main bearings no matter whose bearings you use. You also have to hand fit the rings for proper end gap, and that is also manual grinding. The rest of it didn't require new parts, just cleanup of existing parts. We cleaned the pistons, valves, combustion chambers, etc. but the original parts went back in.
 
AFAIK the first aircraft in service with the R-2600 was the B-25 and North American B-25B Mitchell > National Museum of the US Air Force™ > Display has " the U.S. Army Air Corps accepted the first five B-25s in February 1941". The RAF did not operate the Havoc before 1941 and the R-2600 powered Havoc II was surely not in service over 1940.
The Martin Mariner (PBM) entered service in September 1940 and performed extensive ASW duties in the Atlantic and the PTO

The Boeing C-98 entered service early in 1939 in a civilian capacity as the 314, but when war broke out, were used by the military because of their exceptional range for the duration.

So while the bulk of R-2600 powered aircraft entered service on or about 1941, it did see pre-1941 military operations.
 
The R-2600-3 in 1940 will do 1600 HP for take off, 1400 HP at 11500 ft, used in the B-23. Similar version was the -11, used on the A-20, that also received a few of the -3. Fine 'under 15000 ft' engine, the Merlin XX will make much more power above 15000 ft, with streamlining, exhaust thrust and consumption advantage, while also being a fine 'under 15000 ft' engine on it's own, even in 1940.
The R-2600 should indeed fit in the thread (3 best engines in '40).

Looks like the 1st R-2600 with 1700 HP, and a bit better altitude power was not delivered prior June 1941, ie. too late for this thread.
 
The Martin Mariner (PBM) entered service in September 1940 and performed extensive ASW duties in the Atlantic and the PTO

The Boeing C-98 entered service early in 1939 in a civilian capacity as the 314, but when war broke out, were used by the military because of their exceptional range for the duration.

So while the bulk of R-2600 powered aircraft entered service on or about 1941, it did see pre-1941 military operations.
Thank you for the correction! I had simply quoted the dates of the introduction of the Bristol Beaufighter into combat in an earlier post but clearly that does not work for the countries that were not fighting in 1940. I had read that the R-2600 was originally designed for flying boats but had not bothered to check and to realise that it was in service from 1939.

Using delivery dates rather than combat gives that the first Hercules powered Beaufighter was delivered on 27th July 1940 Bristol Beaufighter - Development and Operational History, Performance Specifications and Picture Gallery compared to 1st September 1940 for the Mariner and 1939 for the 314 Clipper. However, by the end of 1940, it is possible that more Hercules had been delivered as the 100th Beaufighter was delivered in December 1940 (although a few of those may have been Merlin powered Mark IIs).

Using delivery dates does create a small problem as we also know that 18 pre-production Fw 190A-0 aircraft were produced before the first Fw 190A-1 rolled off the production line in December 1940. However, given the poor reliability of the BMW 801 into 1942, we can still dismiss it from a list of best engines for 1940.

The Mitsubishi Kasei clearly does not qualify as the G4M1 was first used in attacks on Chungking and Chengtu in May 1941. possibly using pre-production aircraft delivered over January to March.
 
Like a lot of these threads, an awful lot depends on how we interpret "in service".

Engine production numbers being rather different than aircraft production (engines in transit from engine factory to aircraft factory-like by train across the US, engines sitting at aircraft factory waiting to be installed. engines in airframes as they are worked on.

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Production of the R-2600 was 39 in 1938, 163 in 1939, and 1925 in 1940, granted 351 of the 1940 production was in December alone.

Production of the R-2800 was 2 in 1939 and 17 in 1940- 8 of them in Dec.

The R-2600 may not have seen combat in 1940 but it was certainly flying in something in 1940.
 

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