Luftwaffe "sanity options 2.0", 1935-43

Partly yes, you have quite a big influence on my work, I have already used some of your ideas. I have no problem admitting it, I like to be inspired. However, the very first time I encountered this idea was here: https://www.alternatehistory.com/forum/threads/diesel-kriegsmarine.440313/post-16768086
You had many good points in this thread.
Thank you.
I have similar thoughts, I was already advised to use a former passenger ship for the conversion, due to the higher speed.
FWIW I'm not a fan of liner conversions. I think they're a lot of ship for the number of aircraft they carry. Even ones that are built as prototypes.

For example, I think that all but two of the Japanese liner conversions were a waste of effort because they fell between two stools. That is they weren't good enough to be light fleet carriers and too good to be escort carriers and would have been more useful to the IJN as troop ships. I think the money should have been used to subsidise the construction of more fast tanker analogues of the American Cimarron class which could be converted into useful escort carriers which retained their tanker capability. The exceptions were Hiyō and Jun'yō which were satisfactory rather than good. Whether the Japanese liner conversions was a waste of the resources was the subject of one of the first threads that I started.
The first training vessel will not be perfect, nor can it be expected. The second training ship will be a little better, but still won't be a ship that will ever see combat.
Fair enough and its along the lines of what I think. However, there's nothing in the Treaty of Versailles to stop the Weimar Republic subsidising the construction of fast tankers (rather than faster liners) which could be converted into escort carriers.
Rebuilding the Dithmarschen class tankers is a great idea, I want to implement this idea as well. They will be aircraft carriers with a capacity of around 40 aircraft, which can already be deployed in combat.
IOTL Westerwald/Nordmark supported Deutschland and Altamark/Uckermark supported Graff Spee. Have you though of what they could have done if they'd been completed as equivalents to the American Sangamon class escort carries and were working with the Panzerschiffen instead of supporting them?

The Sangamon and Commencement Bay class escort carriers retained the underway replenishment capabilities of the Cimarron class oilers from which they were converted/upon which they were based and I think the aircraft carrier conversions of the Dithmarschen class would retain their underway replenishment capabilities too so they would still have been able to resupply the Panzerschiffen.

Also there's nothing under the Treaty of Versailles to have them laid down as tankers 1933-34 (instead of 1935-36 as IOTL) but completed as aircraft carriers 1936-37 (instead of as tankers 1939-43 as IOTL). Laying them down 1934-34 ostensibly as merchant tankers under the Nazis unemployment relief scheme might work better because the German shipbuilding wasn't as overloaded with orders as it was in the second half of the 1930s. Then lay down the second group that was planned but not begun 1936-37 instead of the OTL ships. Therefore, I suggest that you do that, if you haven't already thought of it.
 
I have a question...
What would be a suitable fighter for a German aircraft carrier. I'm writing a new story and Germany has a small training aircraft carrier in service in late 1937. The capacity of the aircraft carrier is around 22-26 aircraft. I don't want a Bf 109T, the short range bothers me and additional fuel tanks are not a solution. I was considering the He 112, but the local discussions about this aircraft have somewhat challenged my opinion. Is there a solution other than the He 112 or Bf 109T in 1937 or 1938? And I don't want a Czech Avia, that is, no biplane as a fighter.
Thank you in advance for any opinions and recommendations.
Do the Germans still lay Graff Zeppelin and Aircraft Carrier B down in your story? The OTL ships had the potential to be superb ships because they were larger than the Essex class. Their standard displacement was 1,010 tons more, they were 3in longer at the waterline, 10ft 3in beamier and their engines produced 56,000 more shaft horse power. Fortunately, they were never completed and would have been an even bigger waste of resources if they had been completed, because their detail design would have made them unsatisfactory to useless as aircraft carriers. However, if they had obtained more advice on how to build one from the Japanese and incorporated the lessons learned from your experimental ship.
 
Do the Germans still lay Graff Zeppelin and Aircraft Carrier B down in your story? The OTL ships had the potential to be superb ships because they were larger than the Essex class. Their standard displacement was 1,010 tons more, they were 3in longer at the waterline, 10ft 3in beamier and their engines produced 56,000 more shaft horse power. Fortunately, they were never completed and would have been an even bigger waste of resources if they had been completed, because their detail design would have made them unsatisfactory to useless as aircraft carriers. However, if they had obtained more advice on how to build one from the Japanese and incorporated the lessons learned from your experimental ship.
Yes Graff Zeppelin and Aircraft Carrier B will build but they have different properties than those in OTL. They are a bit bigger (just over 24,000 tons - OTL 23,200 tons), of course they don't have 150mm gun batteries. They will be very similar in appearance to Sōryū. The first ship will also take its rather poor nautical characteristics. Such as the low bow of a clipper which would lead to flooding in rough seas.
However, none of the ships will be completed before September 1, 1939, the first will not be operational until the summer of 1940. The Japanese will cooperate in its construction, but in a slightly different way than they would have liked. Sorry, too much of a spoiler…;)

The smaller aircraft carriers, which will be built from improved tanker hulls, will enter service even later.
 
Some good points made above, i kinda missed the elephant in the room ie the german great interest in GM1 equalling great interest in high alt performance even in 1940, so for ATL scenarios there is a good basis in high altitude german engines appearing earlier. What kind of power levels can we expect from a DB-601E with the DB-603A supercharger? I'm looking at this combo as an ALT-DB-605, instead of boring the engine, slap the bigger supercharger instead.

Probably a tad worse power at high altitudes that what the 605AS gotten?
For comparison sake, the 601E was good for 900 PS at 8 km, 605A (de-rated, for about 15 months of use) did 950, fully rated 605A did 1000 PS there, while the 605AS managed ~1200 PS at 8 km. A big-S/C 601E (let's call it 601ES?) might've gotten us to 1100 HP at 8 km, ie. halfway between the fully rated 605A and the 605AS?
Plenty enough for a Bf 109 to reach 680 km/h at 9 km (ram effect taken into account)- not too shabby for 1943, let alone for the second part of 1942.

(DB 605 was more than just a bored-out 601E, FWIW)

Can they get a better supercharger on the BMW-801C/D? Am i correct in saying that the initial supercharger on the BMW was so basic it didn't even have curved blades? Never mind a two-stage one and never mind more power (yet anyway) , can the BMW-801C/D get a better supercharger that even if not equalling the Merlin-60's 2-stage unit in capability, at least get it closer to it in maintaining high alt power? Something like the E supercharger but on the C/D?
Yes, the impeller that was used on the S/C on 801C/D was indeed not a refined piece of kit. The 801E was probably also with less restricted intakes, to help out with lowering the losses. Mating the S/C section of the 801E to the 801D would've resulted in an engine that mimics the power of the 801D, whille still using the 87 oct fuel.
The early 801S (= power section of the 801D + S/C section of the 801E) should've given the performance of the 190D to an 190A, albeit in 1943.
Other possibilities include the 3-speed drive coupled with the improved S/C (the 1st 801L was supposed to be with the 3-speed S/C, but seems like that never happened; later that designation was recycled for a sibling of the 801D) ; a 2-stage S/C (801R was to be that engine, but it never amounted to a production engine; impellers for it were also more refined than what 801C and D used); turbocharged version, as the 801J that was used on a handful of the Ju 388s (among the 1st turbines that were with hollow blades so these can be cooled by the air stream).

Merlin required the 2-stage S/C in order to stay competitive vs. the bigger engines like the DB 601/605 and BMW 801, while these engines will still be competitive with the 2-stage Merlin with just an improved and big enough 1-stage S/C; historically, Germans were very late even with that, let alone with introduction of 2-stage supercharged engines that would've provided superiority vs. the 2-stage Merlin, as well as parity vs. 2-stage Griffon and turboed R-2800.

All this of course still has a major barrier to it, the crippling lack of high quality materials which as known led to huge amount of time and effort just to get the engines to work with inferior/substitute materials at the design power settings. Can anything be done to improve the high quality metals situation? I guess the absolute minimum is better communication between RLM and the manufacturers when trialling substitutes and finding solutions to valve, sparkplugs, lubrication and other major faults.
If/when the 'power section' of engines is fixed, indeed the bigger/better S/C will work as advertised.
Germany needs to find the way to stockpile as much of nickel and cobalt (needed for "stellite", that was also used for exhaust valves' plating) as well as chromium, and later to import what can be imported. Negotiate to buy chromium mine(s) in Turkey ASAP. Better communication within the RLM is a must, so when one company finds the solution of a problem, the engines of another company can also benefit.
DB will also need to incorporate the oil de-aerator on their engines much earlier than Autumn of 1943, that messed big time both with DB 605 and 603. Liquid cooled engines will require a much sturdier construction, and early.

Ethanol fuel should be widely used, since it burns cooler thus it is less punishing for the engines' internals (important when one lacks materials that won't corrode at very high temperatures), and can be used in high compression engine due to it's high octane rating. Just the usage of ethanol fuel on trainer aircraft would've have huge knock-on effect to the effectiveness of LW.
 
For the topic of German superchargers, I can recommend two books: "Secret horsepower race" and "Flugmotoren und strahltriebwerke". Granted, there is much more to read there, than just about the superchargers, and the 1st book is also about the 'western' engines in general. There is also a book specifically about the Junkers motors, in German, but it is long out of print and very pricy.
Number of superchargers is not related to the number of supercharger speeds. A 2-stage supercharger (ie. two superchargers working in series) is indeed superior to a 1-stage supercharger (ie. just one S/C on an engine). Engine with 4 rated altitudes will make less power for each higher rated altitudes - there is no such thing as a free lunch.
We can take a look on the DB engines with 2-stage superchargers (605L, 603L and LA) - single-shaft layout, infinite number of speeds (okay, in theory) due to the variable-speed drive for the S/C. The 2-stage 3-speed S/C on the Jumo 213E and F was also very capable.
Being big engines (unlike the Merlin or V-1710), already having a big supercharger instead of the 'normal' unit helps a lot with DB and Jumo engines (not the 210). Eg. the DB 605AS (with bigger S/C, taken from the 603A) was making about the same power above 7 km as the Merlin 60 series; yes, the 605L was even better.
I've heard or well, seen those two books mentioned multiple of times and I will probably try to get the Secret horsepower race, as for the other book? I don't speak German and it will be a long time until I could read a technical book in German... Also, wasn't there a Jumo 211F or 211H already by 1940 with a 2 stage supercharger?
As for the need for high-altitude fighters - LW was putting a lot of hope in the GM1 system already in 1940 - points out that a good high altitude engine had it's place even back then. Having a good high altitude engine on the back burner in case that need arises should've been prudent. Even a DB 601E with the S/C from the 603A gets them a high altitude engine on the cheap, and already in 1942.
In the similar vein, have Jumo not wait until 1944 to came out with the 211R (high alt version of the 211 line), do it by some time in 1942, or at least early 1943. Should've helped with night fighters performance a lot.
Use MW 50 on either of these engines for better low and medium altitudes, combined with the swirl throttle, historically copied from the AM-35 and -38 engines.
Those seems reasonable enough. And wasn't that (DB 601E with S/C from 603A) basically the DB 625? Though based on the 605A?
Yes, a working 18 cyl engine was really a no-nonsense approach. It would've given the LW an equivalent of the Ha-42, that was good for 2000 HP on 87 oct and was under 1000 kg. Serves as an excellent 'cushion' against the problems with the fancy engines, and can get another 300-400 HP via MW 50.
Too bad BMW was interested in reinventing the wheel with the BMW 800, and aiming for the moon with the 803.

Another missed opportunity was the BMW 801E, with it's improved S/C and other improvements, 80 pcs were made some time around winter of 1942/43; it took them until late 1944 to slap it's S/C on the 801D to make the 801S.
Indeed, it is probably the merger that lead to this brainrot in the BMW administration now that they no longer had any competition with radial engines... which again is plain stupid to have only one company build radial engines...
Many times, going complicated doomed the engine designs, and not just in Germany. Or at least made the designs mature too late, still a big problem for a piece of military hardware. If something can be done with a relatively simple V12 or R14 engine, aiming for 24, let alone 48 cylinders to do it will not find the buyers, especially if the buyer looks for many, many thousands of engine to be produced.
Have some good link on Porsche's high power aircraft engines?
I am not sure if I would call them complicated, in some cases, making a V16, H24 or 48 cylinder 2000-3000 HP engine is simpler than increasing the HP of a V12 from 1000 to 2000.

And it's not like there are no buyers, the Napier Sabre is the obvious successful 24H engine and the Jumo 222 A/B was also a success that got killed by bureaucracy. Not so sure about the DB604 though, or how well it did.

I guess you could also make the argument that building a 48 cylinder 2000 HP engine from already existing parts is the better way of getting more out of already established production lines, after all, you will only need 10% new machine tools for the overall housing and connecting rods.

Argus I believe used for their 24H engines already existing cylinders. Though I am not sure if it was their own make or Jumo 211s, later 213s? Now that I think about it, I wonder how well a 18R or 24H engine built from Jumo 210G parts would have been if it was ready in 1940-1941?

Edit: I've only seen them mentioned on secretprojects but that's it.
Now that we're at engines - plans from 1938 were aiming for 700/month of Argus 12 cyl air-cooled engines to be produced. Make a simple 7 cyl ~500 HP radial instead; gold-plating the trainers is fool's errand. Even short-stroking the BMW 132 (resulting in the 'German Mercury' equivalent ) is a more economically viable approach. Have these being made in Poland or Bohemia from 1939.
To be fair Argus was a company and needed new orders to stay competitive in the light engine industry and it was before the war. That 12 cyl engine was less powerful than 500 HP. In addition, they had the tooling to build them. Their 24H 1000 HP engine was probably based on it and tbf, that is a good choice from a war production perspective. The problem is that they did not use the chance of putting the tools to good use OTL.

The Argus As 412 (which was based on the AS 17) could have been used instead of the DB600, 601A, Jumo 210 or Jumo 211A in 1937-1940 when there was a lack of high power engines going around, perhaps powering the Do-17 or He 100? If they were to change to a 24H based on the As 410 and then 411 instead of wasting resources in building the low power V12s when Germany couldn't afford the luxury, it would have been an effort well spent. The engine would probably have performed well, reaching something like 1200 HP and with GM-1 or MW-50 1500 HP eventually, is it a good design? Obviously not when the DB601, 605 and Jumo 211 were having similar performance but were lighter V12, however, it would have been an efficient use of available resources and would have kept Argus happy and competitive and perhaps they could have built later on something better.

When Germany got their hands on the Walther aircraft plant in Czechoslovakia they should have continued to build their much powerful V12s to power trainers and other planes in need of a 500 HP engine.

I have no problems that a jet fighter is designed around just one engine, like the Jumo 004M; a short-range fighter, in league of the Fw 190, just start in early 1943. Use the wing and tail bits and pieces from the Fw 190 or Bf 109 (but remove the thickest, innermost part of the wing, resulting in a ~15 sqm wing), and main wheels of the Bf 109 to expedite the work. Main wheels of the 109 were to be used on the OTL He 162.
Going with two engines has it's shortcomings (mainly on fuel supply and supply of engines), but it can offer a possibility of lugging around three MK 103s or equivalent (don't go for the MK 108s there, for Pete's sake).
Mixed propulsion is a good idea, can combine long range with the hefty punch and competitive performance. A mixed propulsion bomber or/and attacker should've been great.
Maybe further develop the He 178 V2? But turn it into a fighter with more common parts from the He 112 and He 100? The V2 supposedly was supposed to have an adjustable intake to solve the 15% thrust loss in the HeS 6a. Later it could perhaps be replaced with the HeS 8a and get something like a 700 km/h aircraft in late 1940 (HeS 6) and late 1942 (HeS 8)
 
I've heard or well, seen those two books mentioned multiple of times and I will probably try to get the Secret horsepower race, as for the other book? I don't speak German and it will be a long time until I could read a technical book in German... Also, wasn't there a Jumo 211F or 211H already by 1940 with a 2 stage supercharger?
211F was in use in 1941, 1-stage 2-speed S/C (same as other 211s). 211H was a version with different reduction gear ratio for the prop.

Those seems reasonable enough. And wasn't that (DB 601E with S/C from 603A) basically the DB 625? Though based on the 605A?
If it was based on DB 605, then it was not based on 601, and vice-versa :)
The 625 was supposed to be with two turbochargers (??), based on the 605D.

I am not sure if I would call them complicated, in some cases, making a V16, H24 or 48 cylinder 2000-3000 HP engine is simpler than increasing the HP of a V12 from 1000 to 2000.

48 cylinders and word 'simple' don't mix well, IMO. Taking for granted that just because an engine has 48 cylinders it will not have the problems associated with low availability of certain metals, or that it will automatically be free from in-built design mistakes - rather not. A big engine will aloso need a modern S/C, or else the enemy with 1500-2000 HP will still beat you at high altitudes.
One does not have to strive to increase the HP of the V12 from 1000 to 2000, but just make one that is close to 2000 HP. If 2500 HP is required, using two 1500 HP engines instead is a very workable alternative since such engines were in actual production, and so were the aircraft with 2x 1500 HP engines.
Lastly, a 3000 HP German (or other people's) engine will dictate a fighter size, weight and price of P-47 or F4U, while without their high-altitude supercharging systems. Check out the F2G Super Corsair vs. the F4U-4, the later beats the heavier F2G above 20000 ft due to having more power there.

And it's not like there are no buyers, the Napier Sabre is the obvious successful 24H engine and the Jumo 222 A/B was also a success that got killed by bureaucracy. Not so sure about the DB604 though, or how well it did.

I guess you could also make the argument that building a 48 cylinder 2000 HP engine from already existing parts is the better way of getting more out of already established production lines, after all, you will only need 10% new machine tools for the overall housing and connecting rods.

I'll avoid making that argument. Every 48 cyl engine is four 12 cyl engines not made. Making an 18 cyl radial, or a big V12 is a far less hassle, and was actually done, in several countries. Even the Sabre looks simple and efficient when compared with an engine that needs two times of most of the parts to equal it.
Take a look at British procurement of 800-1100 HP engines in the second half of 1930s - the 24 cyl Napier Dagger gotten the bread crumbs while V12s and 9 cyl radials were scooping the butter. Excellent call by the British Air Ministry.

Argus I believe used for their 24H engines already existing cylinders. Though I am not sure if it was their own make or Jumo 211s, later 213s? Now that I think about it, I wonder how well a 18R or 24H engine built from Jumo 210G parts would have been if it was ready in 1940-1941?

Edit: I've only seen them mentioned on secretprojects but that's it.

The H24 cyl engine that is a spin off from the Jumo 210 line also gets my vote. I'll assume that it can do 3000 rpm (modest figure for such a short stroke; it would probably be doing 3200-3300 after some development?), at 38L it should've been able to make 1800 HP down low, and 2000 at higher RPM.
Another option might've been a H16 as a spin-off from the Jumo 211 or DB 601?
'W' single-bloc engines were tried after the ww1, including the W18s - so indeed another path worthy of exploring.

To be fair Argus was a company and needed new orders to stay competitive in the light engine industry and it was before the war. That 12 cyl engine was less powerful than 500 HP. In addition, they had the tooling to build them. Their 24H 1000 HP engine was probably based on it and tbf, that is a good choice from a war production perspective. The problem is that they did not use the chance of putting the tools to good use OTL.

The Argus As 412 (which was based on the AS 17) could have been used instead of the DB600, 601A, Jumo 210 or Jumo 211A in 1937-1940 when there was a lack of high power engines going around, perhaps powering the Do-17 or He 100? If they were to change to a 24H based on the As 410 and then 411 instead of wasting resources in building the low power V12s when Germany couldn't afford the luxury, it would have been an effort well spent. The engine would probably have performed well, reaching something like 1200 HP and with GM-1 or MW-50 1500 HP eventually, is it a good design? Obviously not when the DB601, 605 and Jumo 211 were having similar performance but were lighter V12, however, it would have been an efficient use of available resources and would have kept Argus happy and competitive and perhaps they could have built later on something better.

FWIW, I disagree with the notion that Germany needs to make complicated engines to make up for the lack of legacy engines.

Maybe further develop the He 178 V2? But turn it into a fighter with more common parts from the He 112 and He 100? The V2 supposedly was supposed to have an adjustable intake to solve the 15% thrust loss in the HeS 6a. Later it could perhaps be replaced with the HeS 8a and get something like a 700 km/h aircraft in late 1940 (HeS 6) and late 1942 (HeS 8)

I agree with using as much of parts from the existing aircraft, especially the wing from the He 100 (no cooling system there, of course),
By 1943, there should be another 2-3 designs in testing, for 2nd generation.
 
Probably a tad worse power at high altitudes that what the 605AS gotten?
For comparison sake, the 601E was good for 900 PS at 8 km, 605A (de-rated, for about 15 months of use) did 950, fully rated 605A did 1000 PS there, while the 605AS managed ~1200 PS at 8 km. A big-S/C 601E (let's call it 601ES?) might've gotten us to 1100 HP at 8 km, ie. halfway between the fully rated 605A and the 605AS?
Plenty enough for a Bf 109 to reach 680 km/h at 9 km (ram effect taken into account)- not too shabby for 1943, let alone for the second part of 1942.

(DB 605 was more than just a bored-out 601E, FWIW)


Yes, the impeller that was used on the S/C on 801C/D was indeed not a refined piece of kit. The 801E was probably also with less restricted intakes, to help out with lowering the losses. Mating the S/C section of the 801E to the 801D would've resulted in an engine that mimics the power of the 801D, whille still using the 87 oct fuel.
The early 801S (= power section of the 801D + S/C section of the 801E) should've given the performance of the 190D to an 190A, albeit in 1943.
Other possibilities include the 3-speed drive coupled with the improved S/C (the 1st 801L was supposed to be with the 3-speed S/C, but seems like that never happened; later that designation was recycled for a sibling of the 801D) ; a 2-stage S/C (801R was to be that engine, but it never amounted to a production engine; impellers for it were also more refined than what 801C and D used); turbocharged version, as the 801J that was used on a handful of the Ju 388s (among the 1st turbines that were with hollow blades so these can be cooled by the air stream).

Merlin required the 2-stage S/C in order to stay competitive vs. the bigger engines like the DB 601/605 and BMW 801, while these engines will still be competitive with the 2-stage Merlin with just an improved and big enough 1-stage S/C; historically, Germans were very late even with that, let alone with introduction of 2-stage supercharged engines that would've provided superiority vs. the 2-stage Merlin, as well as parity vs. 2-stage Griffon and turboed R-2800.


If/when the 'power section' of engines is fixed, indeed the bigger/better S/C will work as advertised.
Germany needs to find the way to stockpile as much of nickel and cobalt (needed for "stellite", that was also used for exhaust valves' plating) as well as chromium, and later to import what can be imported. Negotiate to buy chromium mine(s) in Turkey ASAP. Better communication within the RLM is a must, so when one company finds the solution of a problem, the engines of another company can also benefit.
DB will also need to incorporate the oil de-aerator on their engines much earlier than Autumn of 1943, that messed big time both with DB 605 and 603. Liquid cooled engines will require a much sturdier construction, and early.

Ethanol fuel should be widely used, since it burns cooler thus it is less punishing for the engines' internals (important when one lacks materials that won't corrode at very high temperatures), and can be used in high compression engine due to it's high octane rating. Just the usage of ethanol fuel on trainer aircraft would've have huge knock-on effect to the effectiveness of LW.
Thanks for the always interesting info. Been looking on the www but i have frustratingly little success, do you have info re the BMW-801E volldruckhohe? How about the Jumo-211R? Also the 1700PS DB-605L TO power is with or without MW-50? Was there scope to increase the L power further?

If i'm what i'm reading is correct, the volldruckhohe for the BMW-801C is only 4600 metres? If so that is rather pathetically low. So they really need it with at least the D rating if technically possible. And then the D with the E rating etc. etc. Later, rather than the fancy and complicated 2-speed 4-stage 801R supercharcher, maybe a more down to earth 2-speed 2-stage unit would be more achievable, to at least roughly match the Spitfire IX at altitude.

Of course, none of the above fiddling would be necessary if the FW-190 is powered by the DB-603 from the start, the 5700m rating is sufficient for 1941, while for 1942-43 something like the 603AA would be quite sufficient to at least match the Spitfire IX at altitude. For 1944 though the L (or the Jumo-213E) is a must to truly match the Spitfire XIV, P-51B/D, P-47D etc at altitude.

Finally, this TL doesn't involve any fuel/oil availability what-if is it? I'm only thinking the kind of danger Jagdwaffe would have posed if they had C3 fuel for all the fighters, better stockpiles of materials, better RLM/ industry communication so that reliability issues can be fixed earlier, and higher altitude rated engines. Even as it was until at least 1942 the Jagdwaffe was ripping the Fighter Command to shreds (with the notable exception of BoB, but even there Jagdwaffe had a positive loss ratio), the score was what, 4 to 1?
 
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Thanks for the always interesting info. Been looking on the www but i have frustratingly little success, do you have info re the BMW-801E volldruckhohe? How about the Jumo-211R?
This should keep you occupied for a while :)
Also this.

Also the 1700PS DB-605L TO power is with or without MW-50? Was there scope to increase the L power further?
With MW 50. Being with high compression and without intercooler, it required the MW 50 and C3 fuel, also for the 30 min rating.
Reducing the compression ratio down to perhaps 6:1, like what Merlin had, would've allowed for an increase of boost, so probably 2 ata for 2000 HP down low? Price being a slight loss of altitude power. Intercooler should've also been an option, like on the DB 603L? Using a lower-speed gearing also favors the max possible power (inevitably at low altitude), at expense of hi-alt power.


If i'm what i'm reading is correct, the volldruckhohe for the BMW-801C is only 4600 metres? If so that is rather pathetically low. So they really need it with at least the D rating if technically possible. And then the D with the E rating etc. etc. Later, rather than the fancy and complicated 2-speed 4-stage 801R supercharcher, maybe a more down to earth 2-speed 2-stage unit would be more achievable, to at least roughly match the Spitfire IX at altitude.

Wrt. the rated altitude of the 801C - depends on what is the bar for comparison. The contemporary 601E was with the rated alt was of 4800m.
Advantage of a more modern S/C is that it draws less power to achieve same boost at a given altitude (and better boost for the same power consumed by it). So the S/C from the 801E to the help, again :)

Of course, none of the above fiddling would be necessary if the FW-190 is powered by the DB-603 from the start, the 5700m rating is sufficient for 1941, while for 1942-43 something like the 603AA would be quite sufficient to at least match the Spitfire IX at altitude. For 1944 though the L (or the Jumo-213E) is a must to truly match the Spitfire XIV, P-51B/D, P-47D etc at altitude.

Fw was in talks with DB about the 603 as early as 1941.
DB was promising/hoping for 1700 HP at 5.1 km as early as April 1940. Even if it is down-rated to 2500 rpm operation, it is still 1550 PS at 5.1 km, ie. still about 250 Hp better than the BMW 801C at that altitude, and 801 can do it 3 minutes vs. 30 min for the 603.
Germans still have a place for a powerful radial, IMO, but with the DB 603 in better shape between 1941 and 1943, the 801 is no longer hard-pressed to do everything, from powering bombers, fighters, night fighters, attackers, prototypes...

Finally, this TL doesn't involve any fuel/oil availability what-if is it? I'm only thinking the kind of danger Jagdwaffe would have posed if they had C3 fuel for all the fighters, better stockpiles of materials, better RLM/ industry communication so that reliability issues can be fixed earlier, and higher altitude rated engines.
Improving the ww2 German fuel situation is worthy of it's own thread :)
 
48 cylinders and word 'simple' don't mix well, IMO. Taking for granted that just because an engine has 48 cylinders it will not have the problems associated with low availability of certain metals, or that it will automatically be free from in-built design mistakes - rather not. A big engine will aloso need a modern S/C, or else the enemy with 1500-2000 HP will still beat you at high altitudes.
One does not have to strive to increase the HP of the V12 from 1000 to 2000, but just make one that is close to 2000 HP. If 2500 HP is required, using two 1500 HP engines instead is a very workable alternative since such engines were in actual production, and so were the aircraft with 2x 1500 HP engines.
Lastly, a 3000 HP German (or other people's) engine will dictate a fighter size, weight and price of P-47 or F4U, while without their high-altitude supercharging systems. Check out the F2G Super Corsair vs. the F4U-4, the later beats the heavier F2G above 20000 ft due to having more power there.
The 48 cylinder engine I have in mind is the FKFS Motor A where it had 4 Hirth 512s connected on the same shaft, similarly to the DB606. Though with an external casing, connecting shaft and supercharger (which was from my understanding its weak spot)

The point is that this way, using weaker, spare engines, you could get a 2000 HP engine by 1940 into production until you get a better one. It is always better to have something bad than nothing honestly, and it's not like the Hirth 512s are going to be used for anything else.

I'll avoid making that argument. Every 48 cyl engine is four 12 cyl engines not made. Making an 18 cyl radial, or a big V12 is a far less hassle, and was actually done, in several countries. Even the Sabre looks simple and efficient when compared with an engine that needs two times of most of the parts to equal it.
Take a look at British procurement of 800-1100 HP engines in the second half of 1930s - the 24 cyl Napier Dagger gotten the bread crumbs while V12s and 9 cyl radials were scooping the butter. Excellent call by the British Air Ministry.
I believe that is a fallacy in the same vein as saying that Germany should have built more Panzer IVs than Panthers, ignoring that the Panther was easier to manufacture.

Sure, it might sound reasonable from a first glance but when you take industrial and manpower considerations it becomes difficult. Let's take the simpler example of a 24H engine. You could make 2 V12 instead of 1 24H engine, but it would take twice as long, twice as many workers, and twice the required tooling, machining, tempering and workshop space. Germany during WW2 had more machine tools than it had workers working on them, building fewer, more complicated and powerful engines would have been less taxing than building more, simpler engines. This way you could also repurpose smaller workshops and factories.

The H24 cyl engine that is a spin off from the Jumo 210 line also gets my vote. I'll assume that it can do 3000 rpm (modest figure for such a short stroke; it would probably be doing 3200-3300 after some development?), at 38L it should've been able to make 1800 HP down low, and 2000 at higher RPM.
Another option might've been a H16 as a spin-off from the Jumo 211 or DB 601?
'W' single-bloc engines were tried after the ww1, including the W18s - so indeed another path worthy of exploring.
That reasonable. I believe there was also a doppelmotor with Jumo 210Bs proposed somewhere.

A H16 using the Jumo 211 or DB601 as a base should theoretically be shorter right? Also, what about making a V12, H12 or X12 engine using the DB604 cylinders as a base?
FWIW, I disagree with the notion that Germany needs to make complicated engines to make up for the lack of legacy engines.
I mean, Argus produced during WW2 something like 30 thousand 400-600 HP V12s, they had the production facilities for the As 410, 411 and As 10/As 17 lying around or being in active use. Why not build a slightly more complicated engine to supplement the lack of V12s pre-war?

Having more powerful engines than just 2 types, DB601 and Jumo 211 during the early years of WW2 seems like a better, strategic plan. If you build more airframes than engines you could use the surplus, if you need to change to a different model than you can afford the pause in production until you retool the factory as you have other engines available.

Though if you want a wholly new design get Deutz to make a V12 2000 HP version of their H24 4000 HP engine. Or a V12 of their 2700 HP V16.
 
Engines, lots of good suggestions here already. My main input is to expan production early. Do delay in db603, early plan for 16 cyl from dB or jumo. 14 and 18 cyl radials.
Here is my version II. For heavy bombers invite bids from more companies and let’s do a good pre-production evaluation of design suggestion’s in 1933-34. Lets assume we will get 4 engine no dive versions from fw, Do, he and Bf and the three for prototypes and another Call in 1937. First version is in limited production from 1937 with the later version in 1940 . From 1940 two German + French production lines.
Transport. Ju52 gets in production. Calls out for long and sturdy transports from 1935 when the first generation projects have concluded. Focus on fast on-off loading (Im thinking ar232 and JU-252).
 
The 48 cylinder engine I have in mind is the FKFS Motor A where it had 4 Hirth 512s connected on the same shaft, similarly to the DB606. Though with an external casing, connecting shaft and supercharger (which was from my understanding its weak spot)

The point is that this way, using weaker, spare engines, you could get a 2000 HP engine by 1940 into production until you get a better one. It is always better to have something bad than nothing honestly, and it's not like the Hirth 512s are going to be used for anything else.

(my bold)
Were there the Hirth 512s laying in the warehouses in such the numbers that it would've been worth to mate 4 of them in one engine? Everyone and his brother was capable of making fighters powered with two 1000-1200 HP engines for 1940 - on what aircraft the 2000 HP 48 cyl is to be installed in 1940?

I believe that is a fallacy in the same vein as saying that Germany should have built more Panzer IVs than Panthers, ignoring that the Panther was easier to manufacture.

Sure, it might sound reasonable from a first glance but when you take industrial and manpower considerations it becomes difficult. Let's take the simpler example of a 24H engine. You could make 2 V12 instead of 1 24H engine, but it would take twice as long, twice as many workers, and twice the required tooling, machining, tempering and workshop space. Germany during WW2 had more machine tools than it had workers working on them, building fewer, more complicated and powerful engines would have been less taxing than building more, simpler engines. This way you could also repurpose smaller workshops and factories.

Panther was bringing to the table worthwhile advancements vs. the Pz-IV, like a much better gun (at least for killing other AFVs) and a much better armor, so I see no argument that it was fallacy to make Panthers in good numbers. In the same vein, the big V12s were a much better choice than the Jumo 210, or the BMW 801 as a much better choice than the BMW 132. All of this while having serious reliability problems due to the issues well known now, that sometimes took more than a year to cure.

IMO, going with 24 cyl engines is analogue to going on with the Tiger, while going with 48 cylinder engines is like going on with the Maus. German 24 cyl engines, for reasons of this or that, were money, time and resources badly spent. Expecting that 48 cyl engines will succeed where the 24 cyl types failed is expecting too much, again IMO.
A H24 engine still requires double of number of pistons, con rods, crankshafts, valves, camshafts, return springs when compared with a 12 cyl engine, injection pump for 24 cylinders, double the number of spark plugs, so there is no 1:2 ratio to be had vs. V12 engines. Two German V12s make 2400 HP total in 1940, not 2000 like it is hoped for the H24, and in 1941 it is 2600-2800 HP for the two V12s.

In favor of the H24 vs. the X24, for example, is that the 'beating' of the pistons and con rods is split to two crankshafts and two crankcases, as well as on twice the number of bearings, while on the X all the beating is focused on a single crankshaft and other internals, resulting in the H24 being likely a less temperamental and more reliable engine (limitations still apply). Going with H24 of perhaps 40-50L instead of the inverted W24 with 66-70L (as the DB 606/610) will produce a more compact and lighter engine, even if it is 2000+ HP engine and not 3000 HP one that comes with another problems like where to install it, and what prop to use. A Fw 190 can live with a 40-50L engine in the nose, while the DB 606 is no-go.

A H16 using the Jumo 211 or DB601 as a base should theoretically be shorter right? Also, what about making a V12, H12 or X12 engine using the DB604 cylinders as a base?
The H16 should've indeed be shorter.
DB 604 was supposed to make 2500 HP at 3200 rpm for take off, per pg. 152 of the 'Flugmotoren und strahltreibwerke' book. 'Square' ratio for the bore and stroke (rare sight back in the day), 135 x 135mm. No data there for altitude power. Cancelled in 1942.
Half of it = 1250 HP for take off, vs. DB 601E making 1350 for take off. 604/2 will be more compact, especially it will be of lower height. Still low power for 1942, but will do good in a small twin?
With such a short stroke, make a H24 engine instead?

The only German H16 engine project that I'm aware was the DVL's concept in cooperation with the DB, 'from 40s', per pg. 149 of the aforementioned book. 33.6L, disc valves, and hopes of 2000 HP. Possibility for coupling two of these was also mooted, for a H32 engine of 4000 HP (general drawing here).

I mean, Argus produced during WW2 something like 30 thousand 400-600 HP V12s, they had the production facilities for the As 410, 411 and As 10/As 17 lying around or being in active use. Why not build a slightly more complicated engine to supplement the lack of V12s pre-war?

Having more powerful engines than just 2 types, DB601 and Jumo 211 during the early years of WW2 seems like a better, strategic plan. If you build more airframes than engines you could use the surplus, if you need to change to a different model than you can afford the pause in production until you retool the factory as you have other engines available.

Every 24 cyl Argus engine is two Ar 96 trainers less. Having LW worse off wrt. trained pilots will not fly well, no pun intended.
A twinned As 410 makes just above 900 HP, down low, while one DB 601A makes 1100-1175 down low, the Jumo 211A = 1000 HP down low, 211B/D = 1200 HP.
The BMW 132, a simple and light engine of 525 kg was making 900 HP; twinned 410 = 630 kg, best case. Bramo 323P, another simple engine, was making 1000 HP down low.
As 410 was a low-altitude engine. and even as twinned is still not an in-slot replacement for the DB 601 nor Jumo 211, while also being worse option than the 9 cyl radials for less shiny aircraft.
As 411 was a later development, its 1200 HP as twinned engine will not cut it for the needs of mid ww2. Argus was making BMW 801s anyway by that time.
 
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I agree with using as much of parts from the existing aircraft, especially the wing from the He 100 (no cooling system there, of course),
By 1943, there should be another 2-3 designs in testing, for 2nd generation.
Heinkel He-200
HEINKEL He-200        He-178-He-100.png

Heinkel He-178 with He-100 wing, landing gear, an extra pair of 20mm cannons and a few small alterations in the overall design.
Tried giving it a tricycle landing gear but didn't like the results. I see this fighter being replaced later with a more advanced design with more powerful engine.
 
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Heinkel He-200
Heinkel He-178 with He-100 wing, landing gear, an extra pair of 20mm cannons and a few small alterations in the overall design.
Tried giving it a tricycle landing gear but didn't like the results. I see this fighter being replaced later with a more advanced design with more powerful engine.
Excellent job.
 
(my bold)
Were there the Hirth 512s laying in the warehouses in such the numbers that it would've been worth to mate 4 of them in one engine? Everyone and his brother was capable of making fighters powered with two 1000-1200 HP engines for 1940 - on what aircraft the 2000 HP 48 cyl is to be installed in 1940?
Not sure, Hirth 508s were at least but I am uncertain how many 512s were made.
As for what aircraft, well, perhaps the cursed He 177 and the more normal Do 17 and Ju 88.

Well, I guess with the same reasoning they could have made a more powerful 48 cylinder engine by mating 4 Jumo 210s.
Panther was bringing to the table worthwhile advancements vs. the Pz-IV, like a much better gun (at least for killing other AFVs) and a much better armor, so I see no argument that it was fallacy to make Panthers in good numbers. In the same vein, the big V12s were a much better choice than the Jumo 210, or the BMW 801 as a much better choice than the BMW 132. All of this while having serious reliability problems due to the issues well known now, that sometimes took more than a year to cure.
The fallacy is that a lot of people believe it would have been better if Germany built more Panzer IVs and Stugs than Panthers and Tigers.

What were the problems with the BMW 132? I've heard that ball bearings or crankshaft was at fault, and, what if the OTL issues with the engine were resolved by 1940?
IMO, going with 24 cyl engines is analogue to going on with the Tiger, while going with 48 cylinder engines is like going on with the Maus. German 24 cyl engines, for reasons of this or that, were money, time and resources badly spent. Expecting that 48 cyl engines will succeed where the 24 cyl types failed is expecting too much, again IMO.
A H24 engine still requires double of number of pistons, con rods, crankshafts, valves, camshafts, return springs when compared with a 12 cyl engine, injection pump for 24 cylinders, double the number of spark plugs, so there is no 1:2 ratio to be had vs. V12 engines. Two German V12s make 2400 HP total in 1940, not 2000 like it is hoped for the H24, and in 1941 it is 2600-2800 HP for the two V12s.
Eh, I think only the DB604 failed while the Jumo 222 A/B was a success, which got killed by Milch upping the requirements. And as we can see the 2xV12 engine configuration failed when used as a replacement for a true 2000 HP engine.

The cylinders, spark plugs, crankshafts etc. are double the number on a V12 but the casting of the engine block, material treatment and other machining is much faster and requires less workers than if you were building 2 V12s. It is also more compact, lighter and utilizes less material than 2 mated V12s.

You could have a FW 190 in 1942 with a 2000 HP Jumo 222.

The H16 should've indeed be shorter.
DB 604 was supposed to make 2500 HP at 3200 rpm for take off, per pg. 152 of the 'Flugmotoren und strahltreibwerke' book. 'Square' ratio for the bore and stroke (rare sight back in the day), 135 x 135mm. No data there for altitude power. Cancelled in 1942.
Half of it = 1250 HP for take off, vs. DB 601E making 1350 for take off. 604/2 will be more compact, especially it will be of lower height. Still low power for 1942, but will do good in a small twin?
With such a short stroke, make a H24 engine instead?
Well that's basically the original DB604 : )
Every 24 cyl Argus engine is two Ar 96 trainers less. Having LW worse off wrt. trained pilots will not fly well, no pun intended.
A twinned As 410 makes just above 900 HP, down low, while one DB 601A makes 1100-1175 down low, the Jumo 211A = 1000 HP down low, 211B/D = 1200 HP.
The BMW 132, a simple and light engine of 525 kg was making 900 HP; twinned 410 = 630 kg, best case. Bramo 323P, another simple engine, was making 1000 HP down low.
As 410 was a low-altitude engine. and even as twinned is still not an in-slot replacement for the DB 601 nor Jumo 211, while also being worse option than the 9 cyl radials for less shiny aircraft.
As 411 was a later development, its 1200 HP as twinned engine will not cut it for the needs of mid ww2. Argus was making BMW 801s anyway by that time.
There were around 3000 Ar 96 built, there were 10 times the number of engines built. The engine I am talking about is not mated, but utilizing components from the As 410 and 411 in a a H24 configuration.

Argus managed to get 1000 HP out of the As 412 engine in 1937 which utilizing As 10 parts. I applied the logic that with the more efficient and powerful As 410 they would get more than that. But even if there's no point in doing that with the As 410, having a 1000 HP engine ready in 1936-37 is better than being in short supply for the DB601 and Jumo 210.

Heinkel He-200
View attachment 873240
Heinkel He-178 with He-100 wing, landing gear, an extra pair of 20mm cannons and a few small alterations in the overall design.
Tried giving it a tricycle landing gear but didn't like the results. I see this fighter being replaced later with a more advanced design with more powerful engine.
Very nice drawing. Though I am not sure it could hold the 2 more 20s there, maybe 13 mms. Or you could add them in the nose at the bottom? (Also, maybe add the He 1078p? Forgot the name square nose for the variable intake?)
 
Very nice drawing. Though I am not sure it could hold the 2 more 20s there, maybe 13 mms.
Yeah after looking at some photos, I should have left off the outer guns or put them in an underwing gondola.

HEINKEL He-200        He-178-He-100++.png


Or you could add them in the nose at the bottom? (Also, maybe add the He 1078p? Forgot the name square nose for the variable intake?)
If I can find some decent line drawings of the He-1078p, I'll take a shot at it.
 
What were the problems with the BMW 132? I've heard that ball bearings or crankshaft was at fault, and, what if the OTL issues with the engine were resolved by 1940?
132 was okay, if behind the curve by 1939 (low power, 900 HP; 1000 HP with hi-oct fuel). 139 was the one with problems, and was redesigned into the 801.

Well that's basically the original DB604 : )
DB 604 was X24. It took a lot of time and effort for X24 engines to work.
H24 engines were less problematic, probably not only for the reasons I've listed above.

Argus managed to get 1000 HP out of the As 412 engine in 1937 which utilizing As 10 parts. I applied the logic that with the more efficient and powerful As 410 they would get more than that. But even if there's no point in doing that with the As 410, having a 1000 HP engine ready in 1936-37 is better than being in short supply for the DB601 and Jumo 210.
From RLM's point of view, is it better to buy one 1000 HP 24 cyl Argus, or two 700 HP Jumo 210s, or perhaps two BMW 132s?
 
Several less conservative engine designs for 1st line combat A/C, make of them what you will.
Air cooled V12, with Bramo 323 or BMW 132 as part donor. Ideally, each cylinder was good for 100-110 HP;12 cylinders = 1200-1300 HP. Possibly a drop-in replacement for the Jumo 211 or DB 601A.
Air cooled H16, with again the 9 cyl engines as part donors, 16 x 100-110 = 1600-1760 HP. Sizable engines due to long stroke. Short-stroking will cut the size down, sorta H16 sibling to the BMW 801.
H16 engine based on the Jumo 211 or DB 601. Start at about 1350 HP, make about 1600 HP by 1940, 1800+ by 1942, 2000 by 1943. Alternative to the Jumo 222, upgrade vs. BMW 801.
V8 engine based on the DB 603, 1200 HP in the early war, shorter, wider and possibly less pricy to make than the 'normal' V12s; upgrade vs. 9 cyl radials.
H24 based on the Jumo 210, 1400 HP out from the box for late 1930s. Keep upgrading it for 3000 rpm operation etc. for 2000+ HP by mid war.
Persist with the Bramo 300, the 18 cyl radial.
 
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132 was okay, if behind the curve by 1939 (low power, 900 HP; 1000 HP with hi-oct fuel). 139 was the one with problems, and was redesigned into the 801.
Ah, my bad, so fixing the 139 problems would result in the 801 or it wasn't as straightforward?
From RLM's point of view, is it better to buy one 1000 HP 24 cyl Argus, or two 700 HP Jumo 210s, or perhaps two BMW 132s?
All of them when there are not enough engines to equip the Luftwaffe. Though I will say it depends where using the 1000 HP matters in 1937-1939, like in the He 100, He 112, FW 187 and Do 17.

This is not an engine with a future let me make it clear, being later on replaced by better V12s and if Argus could push the performance by 1939 to 1350 HP then it would have been a worthwhile investment. It would also give them experience with designing and working on H24 engines.

Several less conservative engine designs for 1st line combat A/C, make of them what you will.
Air cooled V12, with Bramo 323 or BMW 132 as part donor. Ideally, each cylinder was good for 100-110 HP;12 cylinders = 1200-1300 HP. Possibly a drop-in replacement for the Jumo 211 or DB 601A.
Air cooled H16, with again the 9 cyl engines as part donors, 16 x 100-110 = 1600-1760 HP. Sizable engines due to long stroke. Short-stroking will cut the size down, sorta H16 sibling to the BMW 801.
H16 engine based on the Jumo 211 or DB 601. Start at about 1350 HP, make about 1600 HP by 1940, 1800+ by 1942, 2000 by 1943. Alternative to the Jumo 222, upgrade vs. BMW 801.
V8 engine based on the DB 603, 1200 HP in the early war, shorter, wider and possibly less pricy to make than the 'normal' V12s; upgrade vs. 9 cyl radials.
H24 based on the Jumo 210, 1400 HP out from the box for late 1930s. Keep upgrading it for 3000 rpm operation etc. for 2000+ HP by mid war.
Persist with the Bramo 300, the 18 cyl radial.
Reasonable enough, though, is there a particular reason for avoiding the DB605? Or the cylinders of the 605? I remember reading that the people working at DB viewed the 605 more favorable than the 603, believing that the cylinders of the 605 were the perfect dimensions or something like that.

What if they made the 601 from the start with the 605 cylinders?
 
Ah, my bad, so fixing the 139 problems would result in the 801 or it wasn't as straightforward?
From what I can gather, the 801 was a major redesign of the 139.

All of them when there are not enough engines to equip the Luftwaffe. Though I will say it depends where using the 1000 HP matters in 1937-1939, like in the He 100, He 112, FW 187 and Do 17.

This is not an engine with a future let me make it clear, being later on replaced by better V12s and if Argus could push the performance by 1939 to 1350 HP then it would have been a worthwhile investment. It would also give them experience with designing and working on H24 engines.
Two BMW 132s or Bramo 323s can power two Ju 87s, leaving two Jumo 211s for other needs, like to install them on two He 100s, Fw 190s with small wing, or one Fw 187, Ju 88 or He 111.
One As-410 can power just one Ju 87, He 100 or small wing Fw 190, and it will take two of these engines for one Fw 187.

I'd say it is a no brainer what RLM will pay and supply raw materials for during the rearmament of the late 1930s; neither the money nor raw materials will just materialize on the whim.

Reasonable enough, though, is there a particular reason for avoiding the DB605? Or the cylinders of the 605? I remember reading that the people working at DB viewed the 605 more favorable than the 603, believing that the cylinders of the 605 were the perfect dimensions or something like that.

I would certainly love to see whom exactly was of opinion that cylinders of the 605 were of perfect dimensions.
I have no particular reason for avoiding the 605.

What if they made the 601 from the start with the 605 cylinders?

Gain of 5% power?

 
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