1940: the top 3 engines in service

[tomo pauk]

What would be the top three engines in air forces of the world, in service, in the key year of 1940? Whether inline/V-12 or radial, big or small, with provision for prop shaft gun or not. Please tell a bit about your picks.
Flag waving is discouraged

 

[Vincenzo]

i've no doubt on first 2, Merlin and DB 601 in not a particulr order

for the third i propose Sakae

 

[GregP]

For my money it would be the Merlin, the DB601, and the Wright R-1820. The P&W R-1830 was very close but had more cylinders and cost more for about the same power. The Sakae was right there with the R-1830. I simply chose Wright for being a single-row radial that was about the same power but less complex and less costly, but nothing wring with the Sakae at all.

So Vincenzo's picks are just about almost exactly on target. The third one is more preference than demonstrable fact. I know they made significantly more R-1820s than Sakaes, but production volume isn't all that relevant to the core of tghe question.

 

[tomo pauk]

What kind of power was the Sakae developing in 1940, in service?

 

[stona]

No BMW 801? It's difficult to narrow it down to three if you give the first two as the two inline V-12s above

Maybe leave out the DB 601, but that will cause trouble !!! Leave out the Merlin and there will be a riot !!!

What about one of the Jumo engines?

Cheers

Steve

 

[tomo pauk]

No BMW 801?

Not in 1940

Maybe leave out the DB 601, but that will cause trouble !!! Leave ut the Merlin and there will be a riot !!!

Well, I prefer better the 'top 3' rather than 'the best'

 

[Vincenzo]

NK1B nominal power 980 HP @3000 m, 2500 rpm +150mm Hg TO power 1000 HP. 2550 rpm +250mm Hg
NK1C nominal power 950 HP @4200 m, 2500 rpm +150mm Hg TO power 940 HP, 2550 rpm, +250mm Hg

 

[GrauGeist]

I would go with the Jumo211, Allison V-1710 and the DB601

My choices are more aimed at the range of applications and would leave a significant vacuum if removed from the timeline although I'll admit that it's really tough to narrow it down to just three.

 

[stona]

Not in 1940

Fair point

Steve

 

[cherry blossom]

There are three other engines that might be considered.

Hercules radials were powering a very few Beaufighter Mk I during late 1940 (according to Bristol Beaufighter - Variants and Stats "... flying its first sortie on 4/5 September 1940. The first confirmed kill came on 25 October ..."). That may have been the most powerful engine in service during 1940.

The Gnome-Rhone 14N was in widespread service. Shortround6 would tell us that it was nearing its limit and needed a third set of bearings between the cylinder rows (giving the 14R) but it was matching the R-1830 in performance in French aircraft that were tested with both engines over 1939-40. Gérard Hartmann's old article claims 1300 hp for the 14N-48/49 with "100 octane" but we don't know how reliable those engines would have been.

The Japanese Kinsei 43 and 44 was also in widespread service. It gave 1070 hp and was probably slightly inferior to the American engines. It needed to be redesigned with again an extra bearing to give the Kinsei 60 series or Ha-112 II to give 1500 hp from 1943

 

[Aozora]

Hmm...The Merlin in 1940 already had several variants that embodied features such as increased boost ie; Merlin II III with +12 lbs/w 100 Octane; the Merlin XII with 70/30 glycol water plus 100 octane increased boost plus Coffmann starter, and the Merlin XX w/2 speed supercharger plus 100 octane fuel.

The DB 601 series, including the N w/C3 fuel and higher power ratings.

3rd (by a nose from the V-1710) Jumo 211.

Other contenders not already mentioned

Hispano-Suiza 12Y

Bristol Mercury

 

[tomo pauk]

Merlin XX - the best power at altitude (and very competitive at lower altitude), low frontal area, not too heavy. OTOH, can't have the prop gun, 100 oct fuel necessary in order to use higher boost levely, float carb .
DB 601A - can use prop gun, runs fine on 87 oct fuel, has fuel inection, good power at all altitudes.
Bristol Hercules III - good power all around even on 87 oct, not too bulky for a radial. Layout of the exhaust stacks is nothing to brag around, though. Can't use the 100 oct as well as the Merlins or later Hercules versions. Float carb.

 

[stona]

Given that in 1940 the Merlin already powered several of the best aircraft of the war, Hurricane, Spitfire, Mosquito and was about to power the Lancaster and P-51 among others, it is inconceivable that it could be left out.
Cheers
Steve

 

[rochie]

Given that in 1940 the Merlin already powered several of the best aircraft of the war, Hurricane, Spitfire, Mosquito and was about to power the Lancaster and P-51 among others, it is inconceivable that it could be left out.
Cheers
Steve

But Steve, we have a thread going proving the Merlin to be a pile of shite, at least the rolls royce built ones as the packard ones seem to be ok though!

 

[stona]

But Steve, we have a thread going proving the Merlin to be a pile of shite, at least the rolls royce built ones as the packard ones seem to be ok though!

Pile of shite or not, without it we might have been in big trouble!

It wasn't just one of the top three engines in service in 1940, it was one of the top three engines of the war.

Cheers

Steve

 

[rochie]

Pile of shite or not, without it we might have been in big trouble!

It wasn't just one of the top three engines in service in 1940, it was one of the top three engines of the war.

Cheers

Steve

Agreed.

Seems to me the biggest fault with the Merlin was that it was British !

 

[tomo pauk]

Cooler heads in the USAF thought the (either RR or Packard) Merlin was a fine engine.

 

[GregP]

I don't believe there was a lot of reliability difference between Rolls Royce and Packard Merlins. There was a considerable difference in part interchangeability, but in service, British Merlins ran just fine, assuming they weren't sucking dust on a regular basis. The ones that were had issues no matter who made them.

I think people here like to get Packards these days more due to parts availability than to any lack of quality ... and the parts fit without reworking them by hand. Here in the States, most of our parts are U.S.- made parts, but in Europe, the parts are probably largely British in origin. I'm assuming there. Mostly, parts tend to come from the closest source ...

 

[stona]

Well we'd have been a bit daft to build 168,040 unreliable engines (including the 55,523 built by Packard).

In 1940 I'd put the DB 601 in the same class, but nine times more Merlins than DB 601s were eventually produced. You tell me which was the more successful engine.

A special Merlin ran for 15 hours at 1,800 hp and for short bursts at 2,160 hp in 1937 so Rolls Royce knew there was plenty of room for development. By 1945 specially built Merlins running on special fuels were giving 2,780 hp at 36lb boost on test beds. Yep, it really was a terrible engine

Cheers

Steve

 

[wuzak]

There was a considerable difference in part interchangeability, but in service, British Merlins ran just fine, assuming they weren't sucking dust on a regular basis.

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?