After the BoB: rationalization of German/Axis aero engine development & production?

[tomo pauk]

The D-series engines did yes, but they also had a boost up to 2000hp. The boosted Kasei engine's HP was only 1530. Later higher powered Kasei engines increased in weight, such as the 23 series, which was 860kg and a max boost of 1820hp. Regular HP was 1600hp max vs. the D-series 1700hp.

Over-boosted Kasei (92 oct + water-alcohol injection, from mod. 21 on) were doing 1850+- HP. Includes the mod. 21, 22, 25 and 27 used on big aircraft. 801D with overboost were good for 1900 HP; granted those with C3 injection had perhaps another 50 HP?
1650 HP was the max 'non-boosted' power for the later Kaseis, at least per US data (TAIC manuals can be gotten on the internet for free, also on this site); 92 oct fuel used.
Versions that gained weight beyond 760 kg were the ones with counter-rotating props (for floatplanes) and the ones with extension shaft (for Raiden).

Don't forget the German engine also had the Kommandogerät integrated into the engine, which the Japanese one lacked. The Japanese 23 series engine also apparently had some propellor resonance issues as well. Information is lacking on the Japanese engine, so the limited figures might make it seem better than it really was, while with the BMW 801 we have so much info about it we can see all the warts.

Kommandogerät is certainly a good thing to have, but it will not improve engine capabilities just on itself. Mod. 23 Kasei was a mistake, Japanese should've not bothered with it (it was a version with extension shaft), but just go with 'plain Jane' Kasei on the Raiden and accept a few mph speed loss, while improving reliability and lowering the weight and man-hour requirements.
Information about the Japanese engines can be accessed on this forum, the 'Engine' sub-section is a gold mine.

 

[wiking85]

Over-boosted Kasei (92 oct + water-alcohol injection, from mod. 21 on) were doing 1850+- HP. Includes the mod. 21, 22, 25 and 27 used on big aircraft. 801D with overboost were good for 1900 HP; granted those with C3 injection had perhaps another 50 HP?

The MW-30 increase that to 2000 and apparently the -50 to 2100hp.
Question is what caused the BMW to be heavier? I'm thinking the Kommandogerät.

1650 HP was the max 'non-boosted' power for the later Kaseis, at least per US data (TAIC manuals can be gotten on the internet for free, also on this site); 92 oct fuel used.
Versions that gained weight beyond 760 kg were the ones with counter-rotating props (for floatplanes) and the ones with extension shaft (for Raiden).

Kommandogerät is certainly a good thing to have, but it will not improve engine capabilities just on itself. Mod. 23 Kasei was a mistake, Japanese should've not bothered with it (it was a version with extension shaft), but just go with 'plain Jane' Kasei on the Raiden and accept a few mph speed loss, while improving reliability and lowering the weight and man-hour requirements.
Information about the Japanese engines can be accessed on this forum, the 'Engine' sub-section is a gold mine.

The KG was to make the engine easier to use for the pilot in combat, which was a very important boost in effectiveness for a fighter pilot, but not a bad thing for a bomber to have...though did the bomber versions have the device?

Thing about the Japanese engines is they often did not give the performance officially described, see the Homare, due to build quality issues, metallurgy problems, field maintenance, etc.

 

[tomo pauk]

The MW-30 increase that to 2000 and apparently the -50 to 2100hp.
Question is what caused the BMW to be heavier? I'm thinking the Kommandogerät.

Apart from experiments, IIRC there was no MW-30 nor MW-50 use on the BMW 801s. MW-30 should've been allowing for greater boost than MW-50?
BMW 801 was probably over-built (the 801F that was on the test benches by the time war was in last months was to run at 2900 rpm and with 2400+- HP, ie. as the contemporary non-turbo R-2800Cs). K-g was a light item.

The KG was to make the engine easier to use for the pilot in combat, which was a very important boost in effectiveness for a fighter pilot, but not a bad thing for a bomber to have...though did the bomber versions have the device?

Automation of the engine controls is indeed a good thing, though not as good as having a 2-stage S/C (like there was in the Merlin 60 and 70 series) or a working turbo S/C attachment (like on the P-47 or P-38; the BMW 801J - a 801D + BMW's turbo - is a tempting choice for many alternative German late-war aircraft). All 801s have had the K-G.

Thing about the Japanese engines is they often did not give the performance officially described, see the Homare, due to build quality issues, metallurgy problems, field maintenance, etc.

Japanese engines worked very well when Allies took them to the test benches. Soviets tested the water-injected Kinsei from the Ki-46-III and gotten more than 1600 HP; Americans clocked the Homare to 2000+ HP ( 91 oct fuel from US stocks + water injection).
Japanese also have had the late-war problem of not enough of the 91-92 oct fuel, it was probably 87 oct what was available. The Homare with compression ratio reduced from 7:1 down to 6:1 would've lost a tad of altitude performance, but it would've been capable to run with less danger of detonation if the fuel used was 87 oct, rather than prescribed 91-92 oct.
Conversely, if run on German C3 or Allied 130 grade fuel, danger of detonation would've been much lower, even on CR of 7:1.

Still, Homare was not outfitted with a capable enough a supercharger to rival what Anglo-Americans were using from late 1943 on.

 

[mikemike]

BMW 801 weighted about 50% more than Kasei.
In 1940 to the late 1942, BMW 801C/D were as problematic as that was the case for Sabre in the UK in 1941-42, or R-3350 in it's 1st year in service. The BMW 801A used on Do 217 wasn't cleared for the 3 min rating (bar for take off), just the 30 min one and less 'aggressive' ones - probably a reason why their reliability record seem to was decent.

Kasei 11 - 720 kg
Kasei 22 - 860 kg
BMW 801 D-2 1010 kg dry (with ancilliaries, anked engine 934 kg)
A report from December 1941 says there are still persistent problems with the engine, the 801C having a life of about 25 hours, and the aircraft is thus unsuitable for overwater operation.

 

[mikemike]

Over-boosted Kasei (92 oct + water-alcohol injection, from mod. 21 on) were doing 1850+- HP. Includes the mod. 21, 22, 25 and 27 used on big aircraft. 801D with overboost were good for 1900 HP; granted those with C3 injection had perhaps another 50 HP?
1650 HP was the max 'non-boosted' power for the later Kaseis, at least per US data (TAIC manuals can be gotten on the internet for free, also on this site); 92 oct fuel used.
Versions that gained weight beyond 760 kg were the ones with counter-rotating props (for floatplanes) and the ones with extension shaft (for Raiden).


Kommandogerät is certainly a good thing to have, but it will not improve engine capabilities just on itself. Mod. 23 Kasei was a mistake, Japanese should've not bothered with it (it was a version with extension shaft), but just go with 'plain Jane' Kasei on the Raiden and accept a few mph speed loss, while improving reliability and lowering the weight and man-hour requirements.
Information about the Japanese engines can be accessed on this forum, the 'Engine' sub-section is a gold mine.

According to the source I have (Goodwin/Starkings) the vibration problem of the Kasei 23 was solved by modification of the propeller balancing mechanism.

The same source also contends that the Homare had persistent problems with fuel flow and bad high-altitude performance. They also say that the Ki-84, in spite of that, had a max altitude of 12.400 m because the airframe was overpowered by the Homare, and that its propeller was too small to transmit the full engine power at lower altitudes. That's the first time I heard that. If true, it might explain why the Ki-84 variant powered by a Kinsei 62, although lacking about 400 HP, still had quite acceptable performance.

 

[tomo pauk]

Kasei 11 - 720 kg
Kasei 22 - 860 kg
BMW 801 D-2 1010 kg dry (with ancilliaries, anked engine 934 kg)

Kasei 22 weighted 750 kg:

A report from December 1941 says there are still persistent problems with the engine, the 801C having a life of about 25 hours, and the aircraft is thus unsuitable for overwater operation.

No disagreeement from me there - BMW 801C was so problematic that RLM was considering axing it, and the Fw 190 with it.
801D was also run under rpm and boost restrictions more than half a year (until October 1942). Chroimum-plated valves and better spark plugs helped to make the nominal power settings safe to use.

According to the source I have (Goodwin/Starkings) the vibration problem of the Kasei 23 was solved by modification of the propeller balancing mechanism.

Again no problems with that. Just the thing of wasting the most valuable commodity (= time), instead of biting the bullet and go with 'ordinary' Kasei for the Raiden, so it can be had already by early 1943 in good numbers.

The same source also contends that the Homare had persistent problems with fuel flow and bad high-altitude performance. They also say that the Ki-84, in spite of that, had a max altitude of 12.400 m because the airframe was overpowered by the Homare, and that its propeller was too small to transmit the full engine power at lower altitudes. That's the first time I heard that. If true, it might explain why the Ki-84 variant powered by a Kinsei 62, although lacking about 400 HP, still had quite acceptable performance.

Homare was outfitted with 1-stage supercharger, so the lacking hi-alt performance can be expected. Yes, Ki-84 was very light for the power installed, even if that power was lacking beyond 25000 ft when compared with what Allies have had available in the last 15 months of the Pacific War.
Propeller was 10 ft 2 in (per TAIC data), or 9.84 ft (Bunrin Do drawing) - perhaps could've used a prop of extra 1 ft? 'Merlin Mustangs' have had the prop of 11ft 2.4 in; even the P-51 with V-1710 have had a bigger prop than the Ki-84. Although the prop size was probably more detrimental during the climb, rather than during the high speed dash?

 

[wiking85]

No disagreeement from me there - BMW 801C was so problematic that RLM was considering axing it, and the Fw 190 with it.
801D was also run under rpm and boost restrictions more than half a year (until October 1942). Chroimum-plated valves and better spark plugs helped to make the nominal power settings safe to use.

Sounds like a job for the Jumo 222...

 

[tomo pauk]

Sounds like a job for the Jumo 222...

I'll humbly call Snowygrouch , so we can hear his insight about the viability of the Jumo 222 in 1942-43

 

[wiking85]

I'll humbly call Snowygrouch , so we can hear his insight about the viability of the Jumo 222 in 1942-43

Or you could read what the head engineer of the engine had to say....

Jumo 222: what's the truth?

Hate was not the motivation insofar as it was power; the hate came from the threats to power that Goering and Milch represented to one another. Its the same reason Koppenberg had to go; he was too powerful and needed to be dealt with so Milch could reclaim supreme authority in his sphere. So...

ww2aircraft.net

 

[Shortround6]

Or you could read what the head engineer of the engine had to say....

and the head engineer was totally unbiased?

Just like Sir Roy Fedden would give a totally unbiased appraisal of the sleeve valve program at Bristol?

Or the Management at Curtiss-Wright giving a totally unbiased appraisal of the Tornado and R-3350 programs and the engine designers (technical people ) agreeing with them 100%?

One of the management people tried to blame Nutt for not calling on outside help, in the form of Harry Miller, to help solve the valve problems in the Tornado. Miller had done preliminary design work on several aircraft engines but the USAAC was having none of it and refused to fund any of his projects except the engine used in Preston Tucker's fighter and those engines were never completed and run. Miller was a bit over rated as he needed both Leo Goossen and Fred Offenhauser to actual build engines that would win races.

Or the US Army guys who started the Continental IV-1430 program (Continental just built parts to the army's design) not giving up until 1944-45 despite the engine never coming close to the desired/promised power or reliability.

 

[wiking85]

and the head engineer was totally unbiased?

If other sources didn't match what he said based on independent documentation I'd agree with you about bias, but it seems he was being quite honest.

This book supports Brandner's version of events:
Amazon product

As does this two part series of articles:

• Holger Lorenz: Jumo 222. Brandners Geniestreich. In: Flugzeug Classic Nr. 7/2021, GeraNova, München, ISSN 1617-0725, S. 30–37.
• Holger Lorenz: Jumo 222. Milchs Machtpoker. In: Flugzeug Classic Nr. 8/2021, GeraNova, München, ISSN 1617-0725, S. 68–74.

And this older one:

1. Karl Kössler: Dichtung und Wahrheit – im Fall der Ju 288. In: Luftfahrt International 3/81, S. 109–113.

No disagreeement from me there - BMW 801C was so problematic that RLM was considering axing it, and the Fw 190 with it.
801D was also run under rpm and boost restrictions more than half a year (until October 1942). Chroimum-plated valves and better spark plugs helped to make the nominal power settings safe to use.

Anyway, given that the Jumo 222 had 2000hp as of 1942 and was declared reliable after 20x 100 hour bench tests and multiple flights with 3x converted Ju-52s as well as 6 prototype Ju288s that flew without significant issues with the engine it was well in advance of the BMW801 in terms of being ready for service. Regarding replacing the BMW engine in the FW190 since the 222 was about the same weight and dimensions, but significantly higher powered and only used B4 fuel instead of C3 and C3 or MW injection, it would have been the superior choice for the aircraft. Even if just a replacement for the FW190C/D. If the E/F series ever got into mass production it would have been a world beater in such a configuration or the TA-152. Though even the A/B-2 type with boost up to 2500hp would have been just as desirable despite the lack of two stage two seep supercharging.

 

[Snowygrouch]

If other sources didn't match what he said based on independent documentation I'd agree with you about bias, but it seems he was being quite honest.

This book supports Brandner's version of events:
Amazon product

As does this two part series of articles:

• Holger Lorenz: Jumo 222. Brandners Geniestreich. In: Flugzeug Classic Nr. 7/2021, GeraNova, München, ISSN 1617-0725, S. 30–37.
• Holger Lorenz: Jumo 222. Milchs Machtpoker. In: Flugzeug Classic Nr. 8/2021, GeraNova, München, ISSN 1617-0725, S. 68–74.

And this older one:

1. Karl Kössler: Dichtung und Wahrheit – im Fall der Ju 288. In: Luftfahrt International 3/81, S. 109–113.

Anyway, given that the Jumo 222 had 2000hp as of 1942 and was declared reliable after 20x 100 hour bench tests and multiple flights with 3x converted Ju-52s as well as 6 prototype Ju288s that flew without significant issues with the engine it was well in advance of the BMW801 in terms of being ready for service. Regarding replacing the BMW engine in the FW190 since the 222 was about the same weight and dimensions, but significantly higher powered and only used B4 fuel instead of C3 and C3 or MW injection, it would have been the superior choice for the aircraft. Even if just a replacement for the FW190C/D. If the E/F series ever got into mass production it would have been a world beater in such a configuration or the TA-152. Though even the A/B-2 type with boost up to 2500hp would have been just as desirable despite the lack of two stage two seep supercharging.

Given that you`ve told everyone to read a German document, it would probably be appropriate for you to briefly summarise what exactly it is you think he`s saying....

According to the RLM stenographic record, in September 1943, the Jumo222 bearings were still proving so troublesome that Milch told Jumo to go and speak to the bearing people at Daimler, to try to get somewhere with it.

Please provide an official German type test document where the Jumo 222 is "declared reliable" in 1942.

If you read post-war Allied interrogations of Jumo engineers, useful information emerges.

Referencing an unavailable book in German which costs about $400, without posting ANY quotes... you regard this as useful ?

Even in October 1943 they were still working on the 222 bearings.

 

[wiking85]

Given that you`ve told everyone to read a German document, it would probably be appropriate for you to briefly summarise what exactly it is you think he`s saying....

Given that I've already done so repeatedly in multiple threads and was just showing my sources for my claims, there isn't a need to do so yet again. If you'd like me to post the relevant pages I can scan them later.

According to the RLM stenographic record, in September 1943, the Jumo222 bearings were still proving so troublesome that Milch told Jumo to go and speak to the bearing people at Daimler, to try to get somewhere with it.

Ah fuckery through lack of context. That's a relatively new one for this argument.
In September 1943 the only Jumo 222 engine version that was being worked on was Milch's demanded 2500hp A/B-3 engine (and the E/F series which was the same, but with an enhanced supercharger for high altitude operations). So you're document is only showing the situation of an engine type I wasn't even talking about, that is the original 2000hp A/B-1 (really even the -2 series by 1943) Jumo 222.

Please provide an official German type test document where the Jumo 222 is "declared reliable" in 1942.

You know I don't have access to Junkers' company files, so have to go off what the chief engineer stated in his memoir, what Lutz Budrass has to say, and the magazine articles I posted have to say.

If you read post-war Allied interrogations of Jumo engineers, useful information emerges.

View attachment 644846

Again of the A/B-3 model, since the other two were cancelled by the RLM. This is reverencing a different engine to what I was talking about. There was the English language article on it that broke down the engines by type and their situations:

Junkers Jumo 222 Aircraft Engine

The Junkers Jumo 222 24-cylinder inline radial was intended to be the next generation of German aircraft engines during WWII. Developmental issues and material shortages prevented its production.

oldmachinepress.com

This covers the different subtypes and what was being worked on in 1943 (aka not the 2000hp model I'm talking about, rather the 2500hp model supposed to enter production in October 1944, the A/B-3 series.

Since you have the entire page apparently can you post the entire document in context? When you show such a narrow excerpt it seems like you have something to hide.

Referencing an unavailable book in German which costs about $400, without posting ANY quotes... you regard this as useful ?

I was referencing my posts. The Brandner memoir excerpt is already available. If you want me to scan the pages in question I can do that later. No one asked me to until you made your rude comments above. In the future if you'd like that just ask politely and don't behave like a dick.

Even in October 1943 they were still working on the 222 bearings.

View attachment 644847

Already addressed the differences between the A/B-1 and A/B-3 above. But nice try to lie by obfuscation and to look like you're posting relevant information by posting pictures totally out of context.

 

[Snowygrouch]

Given that I've already done so repeatedly in multiple threads and was just showing my sources for my claims, there isn't a need to do so yet again. If you'd like me to post the relevant pages I can scan them later.


Ah fuckery through lack of context. That's a relatively new one for this argument.
In September 1943 the only Jumo 222 engine version that was being worked on was Milch's demanded 2500hp A/B-3 engine (and the E/F series which was the same, but with an enhanced supercharger for high altitude operations). So you're document is only showing the situation of an engine type I wasn't even talking about, that is the original 2000hp A/B-1 (really even the -2 series by 1943) Jumo 222.

You know I don't have access to Junkers' company files, so have to go off what the chief engineer stated in his memoir, what Lutz Budrass has to say, and the magazine articles I posted have to say.

Again of the A/B-3 model, since the other two were cancelled by the RLM. This is reverencing a different engine to what I was talking about. There was the English language article on it that broke down the engines by type and their situations:

Junkers Jumo 222 Aircraft Engine

The Junkers Jumo 222 24-cylinder inline radial was intended to be the next generation of German aircraft engines during WWII. Developmental issues and material shortages prevented its production.

oldmachinepress.com

This covers the different subtypes and what was being worked on in 1943 (aka not the 2000hp model I'm talking about, rather the 2500hp model supposed to enter production in October 1944, the A/B-3 series.

Since you have the entire page apparently can you post the entire document in context? When you show such a narrow excerpt it seems like you have something to hide.

I was referencing my posts. The Brandner memoir excerpt is already available. If you want me to scan the pages in question I can do that later. No one asked me to until you made your rude comments above. In the future if you'd like that just ask politely and don't behave like a dick.

Already addressed the differences between the A/B-1 and A/B-3 above. But nice try to lie by obfuscation and to look like you're posting relevant information by posting pictures totally out of context.

Swearing at me ?

OK end of dialogue.

Literally unreal behaviour from someone who admits to having no access to the proper documents. I was actually searching my RLM records to find you
the actual discussion, but.. thanks to your behaviour, thats not appearing here anytime soon.

This thread is going into my "why do I bother" evidence folder.

 

[FLYBOYJ]

Folks - please stop the foul language banter. Dropping an "F" bomb during a technical debate just makes you look ignorant! My only warning.

 

[wiking85]

Swearing at me ?

OK end of dialogue.

Literally unreal behaviour from someone who admits to having no access to the proper documents. I was actually searching my RLM records to find you
the actual discussion, but.. thanks to your behaviour, thats not appearing here anytime soon.

View attachment 644849

This thread is going into my "why do I bother" evidence folder.

Ok, so instead of responding to anything I said, you're just 'taking your ball and going home' because you don't like a since word. Sounds like you don't have any actual argument and don't want to demonstrate anything that could show you don't know what you're talking about on this subject. You haven't engaged in a dialogue here, just started out being quite rude and just showed a couple of pictures out of context to show you have some paperwork and when challenged you seize on a single word as a reason not to do anything more than show another single out of context single sentence. I'd say your contribution in this thread has been exceptionally unhelpful so far.

 

[FLYBOYJ]

I'd say your contribution in this thread has been exceptionally unhelpful so far.

And I'm going to say your contribution in this thread is now pissing me off. KNOCK IT OFF!

 

[DerAdlerIstGelandet]

 

[sotaro]

oh well.