Luftwaffe "sanity options 2.0", 1935-43

Alternative small engines, for trainers, recons and light transports:
- V6, based on a BMW 132 or Bramo 323
-I6, again based on these engines
- V8 made from the Jumo 210,
- I6, based on the Jumo 211 or DB 600
- I4, based on the DB 603
- 'German Mercury', ie. short-stroked 132 or 323 radial
- Same basis, but a 7 cyl radial engine, just under 20L

Basically, aiming for a 500 PS bracket, +-10%. As one can see, I've tried to keep the number of engine parts down.
 
Just a comment on DB-603/Jumo-213 after i've done some reading. It seems their much delayed introduction stems from the fact that the RLM wanted to jump too far, ie from 1000 PS engines to 2000 PS, hence the Jumo-222/DB-604 orders in 1937. This is probably the reason the DB-603 was shelved in 1937, and the agonizing long development of the Jumo-213. They wanted to run before walking so to speak.

So the sane option is of course to first give top priority to 1500 PS engines, and only when they're ready the 2000 PS engines should be pursued. In this case, having 1500-1600 PS DB-603/Jumo-213 in 1941 is the proverbial bird in hand (followed in 1942 by the 1750 PS models, and in 1943-44 by various other high-altitude and boosted variants of 2000 PS plus). In OTL around 18,000 of them were built, but in this ATL being ready earlier more of them would be built, so let's say twice as many are build, ie around 36,000. That alone would be a significant improvement for Luftwaffe.

Going in the same vein, priority to something like the Ju-188 should be gived first, which powered by the engines above should be ready in 1941 or so alongside the Do-217.

The above can coupled with an earlier merger of BMW and Bramo so that the combined design resources are used to hopefully bring forward the BMW-801 a year earlier. The overall numbers can't be increased by much though, let's say 30,000 are made compared to 28,000 in OTL. But ideally, bringing the higher powered versions roughly a year earlier would be another significant improvement.
 
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So the sane option is of course to first give top priority to 1500 PS engines, and only when they're ready the 2000 PS engines should be pursued. In this case, having 1500-1600 PS DB-603/Jumo-213 in 1941 is the proverbial bird in hand (followed in 1942 by the 1750 PS models, and in 1943-44 by various other high-altitude and boosted variants of 2000 PS plus). In OTL around 18,000 of them were built, but in this ATL being ready earlier more of them would be built, so let's say twice as many are build, ie around 36,000. That alone would be a significant improvement for Luftwaffe.

That way the brave new 2500+HP engines are cancelled without much of regret come 1944, allowing the companies to focus on the jets.

The above can coupled with an earlier merger of BMW and Bramo so that the combined design resources are used to hopefully bring forward the BMW-801 a year earlier. The overall numbers can't be increased by much though, let's say 30,000 are made compared to 28,000 in OTL. But ideally, bringing the higher powered versions roughly a year earlier would be another significant improvement.

Earlier merger might've also resulted in an actual introduction of an 18 cyl radial. Talk 2000 HP on 87 oct, perhaps making 2300-2400 HP with MW 50?
 
Well, for this particular scenario, i would have any 18 cylinder work cancelled as well, just getting the bird -in- hand 2000 PS plus DB-603/Jumo-213/BMW-801 variants by 1943 or so, and preferably with 2 stage superchargers on the first two at least (with the 801 remaining a low/medium alt engine?), would be a massive improvement for LW.
 

ric350

Kicked
Have the Luftwaffe train their radio operators to be very very vigilant in their use of Enigma. My understanding is their cavalier use made life a lot easier for the code breakers.

ric350
 
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?)
Inspired by the He-1078, later versions of the He-162 and some other Luft. 46 designs, here's how I envision the He-178 to the fictional He-200 to a late war design.
He-200-projekt--$.png

Swept wings and tail, more streamlined fuselage square shaped air intake and tricycle under carriage.
Looks a little like the F-86 even though I was kind of aiming for a Mig-15 look ala the Focke Wulf Ta. 183.
I call it the Heinkel He-202, totally fictional but does incorporate ideas from late war Heinkel designs and a little from Messerschmitt.
 
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Well, for this particular scenario, i would have any 18 cylinder work cancelled as well, just getting the bird -in- hand 2000 PS plus DB-603/Jumo-213/BMW-801 variants by 1943 or so, and preferably with 2 stage superchargers on the first two at least (with the 801 remaining a low/medium alt engine?), would be a massive improvement for LW.

Yes, with that choice of powerful engines, the need for an 18 cyl type is not existant.
BMW 801 had it's chance with the 801E, and with switching to the 2-stage supercharged variant (talk simpler 801R, or the P.8028 - top pic; note the chin intercooler through what the air is pushed from the 'auxiliary' stage to the 'engine stage'). Fw 190 with a 2-stage 801 should be in the ballpark with the F4U-4, ie. 700+ km/h; that also puts it in Merlin Mustang and Spitfire XIV category.

With removal of anything else at BMW, they ought to focus on the jet engine better. They already know that turbines with hollow blades work when the hot exhausts are in question.
 
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.
The RN submarine service thank you and send you a xmas card :p
 
Alternative path for BMW engines development, and BMW in general:

Instead of the small 116 and medium-sized 117 V12 engines, they embark on making a big, 40L V12 by 1936. Production starts in 1938, with He 111 as the 1st recipient. Engine makes 1400 HP down low, and 1200 HP at 4 km. 800 kg dry weight. Future Fw 190 takes the flight with that engine, also the Bf 109X, that enters the service in mid 1940, being the only LW fighter in service that is faster than Spitfire.
In the mean time (1938), BMW acquires Hirth motoren, whose owner tragically dies as per OTL.
During the winter of 1940/41, improved version is in production, making 1500 HP down low, and 1300 HP at 5 km (ie. comparable with AM-38 + AM-35A power levels). Fw 190 makes 650 km/h with it, and it's introduction is almost trouble-free in 1941. Fiat acquires the licence for the big V12, that is now 850 kg heavy.

A push towards even greater power levels hits the brick wall of corroded exhaust valves and insufficient lubrication of the low part of the engine.
Production of BMW 132 is outsourced to Hirth.

Chrome-coated exhaust valves and lubrication system with a de-aerator solve these problems by mid-1942, that combined with the more refined supercharger and a bit extra RPM makes the big V12 doing 1500 HP at 5.5km, and 1700 HP at low level. Fw 190 does 680 km/h with it.
(basically mimics the AM-39 nominal power, or Jumo 213A max power)
If C3 fuel is used, another 10% power is gained, at a bit lower altitude.
BMW doubles up the effort wrt. jet engines together with Hirth.
Winter of 1943/44 sees the big V12 getting a really big supercharger, MW 50 system, also the swirl throttle is employed, dry weight 900 kg. Power level on par with DB 603E, for 700+ km/h Fw 190.
 
"Build more aircraft, and Erhard Milch will beat a path to your door!”

When Speer briefed on the number of aircraft to be built in 1943 & beyond the response amounted to, 'where will we find the pilots for them.' The training program for the Luftwaffe was inefficient and wholly inadequate. In 1940 the RAF could put a basic fighter pilot in the air in 90 days, with a bit over 200 flight hours. The Luftwaffe had well over 250 hours on the Syllabus, but they were still using a extended prewar program designed to create well rounded airmen, & the program required well over six months.

AFAIK the Luftwaffe had the ground crew to absorb the extra production. E.g. I mentioned the transfer of some of the ground crew to form the field divisions in Post 137. However, a shortage of aircraft (rather than a shortage) of personnel retarded the growth of the Luftwaffe since before the POD.

The Luftwaffe would need more aircrew for the extra aircraft. Some of the extra aircraft would be trainers, but where do the instructors come from? OTOH the Luftwaffe borrowed aircraft & instructors from the training schools to bring the first-line units to full strength for major operations, which reduced the output of trained aircrew. The infamous was Stalingrad. Here the Luftwaffe has more aircraft and if it can find more instructors to train more aircrew there's less need to borrow aircraft & instructors from the training schools. Therefore no reduction in the output of trained aircrew and over time the gap between the number of extra aircrew and the number of extra aircraft narrows. The vicious circle of OTL is replaced by a virtuous circle ITTL.

The RAF, US AAF, and USN approach was to rotate veteran pilots back to the schools to expand instructor staff. Initially this degraded squadron strength/skill, but as the training establishment grew and concentrated wartime training syllabus was implemented the school output was increased to requirement. So much so the US and Brits were able to increase the school flight hours. During 1943 the RAF peaked out at 350+ hours, the AAF at 300+. meanwhile the Luftwaffe had cut its curriculum to 170 flight hours.

The extra aircraft won't fly without fuel. Therefore, what can be done to increase Germany's supply of aviation fuel between 1935 and 1943?

It starts with accepting the wars cannot all be confined to a few months. that there is likely to be a long resource demanding war before 1943. For political reasons the official nazi line was any wars before 1942-43 would be limited and short. This translated into priorities for fuel going in other directions and underproduction of aviation grade fuel. This was a difficult problem since Germany had near zero internal sources. The tiny Austrian oil field, and the Polish oil field captured in 1939. Neither gave Germany the smallest fraction of self sufficiency. Development of synthetic fuel requires a robust program starting before 1935 at least. Perhaps NLT 1925. Long before the nazis take over.
 
Aternative Fw 190 paths/options:
Take the advantage of the initial two Fw 190 prototypes being a small and light aircraft, install the DB 601, or at least the Jumo 211 - sane RLM should've jumped into the opportunity to have Fw 190 to be powered by either.
Wing area was smaller even than that of Bf 109, MC.202 or the mainstream Soviet fighters (Yak-1/7/9, La/Lagg, MiG 1/3) had, and about the same as what the Yak-3 had.
Here is how the Jumo 211-powered version might've looked like (not the 1st time I've posted this :) ):
190 211.jpg

Should be giving 600+ km/h with 1200 HP Jumos (1940), and perhaps 630-640 km/h with later versions (1941 and on) - plenty enough to fight anything the RAF had before Spitfire IX and Typhoon, and very viable at N. Africa, let alone in the East. A far less problematic fighter in service than the BMW-powered 190s, can be had in good numbers everywhere already by late 1941 instead of late 1942, since there is no switch to the big wing, no relocation of cockpit due to heavier engine, and no severe problems with BMWs between 1938 and 1942.

Compared with the Bf 109, it has more fuel, better undercarriage and cockpit, has greater internal useful volume (much due to the taller fuselage) and it rolls much better.

For the Fw 190s with heavy and powerful engines, an earlier switch towards the big wing (20-ish sqm) might be a good idea.
 
Yes, with that choice of powerful engines, the need for an 18 cyl type is not existant.
BMW 801 had it's chance with the 801E, and with switching to the 2-stage supercharged variant (talk simpler 801R, or the P.8028 - top pic; note the chin intercooler through what the air is pushed from the 'auxiliary' stage to the 'engine stage'). Fw 190 with a 2-stage 801 should be in the ballpark with the F4U-4, ie. 700+ km/h; that also puts it in Merlin Mustang and Spitfire XIV category.

With removal of anything else at BMW, they ought to focus on the jet engine better. They already know that turbines with hollow blades work when the hot exhausts are in question.
It's also greatly beneficial by not introducing yet another engine in production, if the DB/BMW/Jumos can be developed to 2000-2200PS early enough.

You might have a better grasp of this, would it be accurate to say that a 3 gun, Jumo-213E/DB-603L equipped Ta-152B/C models would be at least equal, and likely superior at altitude to Spitfire XIV, P-51D, P-47D? Only the very latest 1945 light-weight P-51H or similar and P-47M/N and perhaps the very latest Griffon Spitfires equalling and maybe getting a bit ahead again?

The various single stage Jumo-213/DB-603 models coupled with MW-50 on the FW-190C/D type airframes would produce formidable, roughly 700 kph medium altitude fighters, especially if ready by late 1943.

And a question on DB-605L, it's TO rating of 1700PS at 1.75 ata seems a little low to power a 109K airframe (even if altitude performance is very good). Could it be cleared for higher TO and low/medium alt powers, approaching the ASM/DM models? I recall reading you saying elsewhere that 1.9-1.95 ata might be achievable, so that would be 1850-1900 PS TO?
 
Ta 152 B/C were five gun as they both had a motor cannon, cowl guns and wing root guns. Not got my references to hand but they probably could take armament in the outer wing too.
Both were largely redesigned Fw 190 airframes, the stillborn/cancelled Ta 153 was a completely new airframe.
The Ta 152H was more than a match for the Mustang, the other two never saw service although two production Ta 152C-1s were delivered to JG301 in Feb? ‘45.
 
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Part of Post 140.
Could Germany have built more aircraft (and spares) 1935-43 ITTL? However, as the Nazis came to power in January 1933 that would be a better time to start.
Part of Post 143.
Yes, they could've been making more aircraft, or, they could've make the LW more capable on same money. Several changes:
- once He 111 is a thing (1935-36), the Do 17 needs to go away.
Also more He111s in place of the Ju86.

One book about the Luftwaffe that I read clamed that enough material build 1,000 aircraft was left after the Ju86 was cancelled as a bomber and that during World War II someone suggested that it be used to build 1,000 Ju86 trainers to supplement the Ju52/3ms. If that's correct the Luftwaffe could have had 1,000 extra He111s in 1939 in addition to the He111s built instead the Ju86s that were completed IOTL.
 
You might have a better grasp of this, would it be accurate to say that a 3 gun, Jumo-213E/DB-603L equipped Ta-152B/C models would be at least equal, and likely superior at altitude to Spitfire XIV, P-51D, P-47D? Only the very latest 1945 light-weight P-51H or similar and P-47M/N and perhaps the very latest Griffon Spitfires equalling and maybe getting a bit ahead again?
Superior to the P-47D, at all altitudes, both in climb and speed, and indeed at least comparable with the P-51D and Spitfire XIV.
From the German point of view, trying to equal the P-51H and the similar with jets (and then some) would've been a much better bet . We can recall that jet engine pre-date the DB 603L and Jumo 213E by more than a year - a huge time period for the ww2.
Without the GM1 in picture, the Fw 190D with Jumo 213F (low-drag airframe + low-drag engine) was probably the fastest among the piston-engined fighters for the LW, even if we don't believe in the 760 km/h mark.

The various single stage Jumo-213/DB-603 models coupled with MW-50 on the FW-190C/D type airframes would produce formidable, roughly 700 kph medium altitude fighters, especially if ready by late 1943.

As the OTL 190D was.

And a question on DB-605L, it's TO rating of 1700PS at 1.75 ata seems a little low to power a 109K airframe (even if altitude performance is very good). Could it be cleared for higher TO and low/medium alt powers, approaching the ASM/DM models? I recall reading you saying elsewhere that 1.9-1.95 ata might be achievable, so that would be 1850-1900 PS TO?
1700 PS for take off for a 109 was more than was needed. The much heavier P-51D was with under 1500 HP for take-off.
The 605L already required C3 and MW50 (75 L/h) for 2600 rpm and 1.43 operation, due to the very high compression ratio (8.5:1 or 8.3:1)and no intercooler. It needed 150 L/H of MW50 for 2800 rpm and 1.43.
What could've been done is slashing the CR down to 6:1 (as in the Merlin), or at least keep it under 6.5:1. Lower CR = greater boost is possible = greater power. Trade-off will be a slight loss of power at high altitudes, that I see as a good deal.
Intercooler would've helped, but it will require additional volume for radiator, and spare volume on the 109 was at a premium.

Ta 152 B/C were five gun as they both had a motor cannon, cowl guns and wing root guns. Not got my references to hand but they probably could take armament in the outer wing too.
The central weapon placement was perhaps a consequence of the desire to install extra fuel tankage (in bags) between the spars? Thus basically doubling the internal takage vs. 190D-9 for example.
One book about the Luftwaffe that I read clamed that enough material build 1,000 aircraft was left after the Ju86 was cancelled as a bomber and that during World War II someone suggested that it be used to build 1,000 Ju86 trainers to supplement the Ju52/3ms. If that's correct the Luftwaffe could have had 1,000 extra He111s in 1939 in addition to the He111s built instead the Ju86s that were completed IOTL.
Good call. Ju 86s were behind the curve big time when the shooting started.
 
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And a question on DB-605L, it's TO rating of 1700PS at 1.75 ata seems a little low to power a 109K airframe (even if altitude performance is very good). Could it be cleared for higher TO and low/medium alt powers, approaching the ASM/DM models? I recall reading you saying elsewhere that 1.9-1.95 ata might be achievable, so that would be 1850-1900 PS TO?
Not the answer to your question, but with it's high compression ratio and relatively high boost, the DB 605L would've been a good user of the ethanol fuel since these fuels thrive in that environment due to their high octane value equivalent and low burn temperature..
 
Part of Post 140.

Part of Post 143.

Also more He111s in place of the Ju86.

One book about the Luftwaffe that I read clamed that enough material build 1,000 aircraft was left after the Ju86 was cancelled as a bomber and that during World War II someone suggested that it be used to build 1,000 Ju86 trainers to supplement the Ju52/3ms. If that's correct the Luftwaffe could have had 1,000 extra He111s in 1939 in addition to the He111s built instead the Ju86s that were completed IOTL.
Green’s Warplanes of the Third Reich. Don’t think it was that many, more like 100 at most. The proposal was to give them petrol engines and issue them to the training units. Me? Sell them to Spain or Turkey for materials.
 
Superior to the P-47D, at all altitudes, both in climb and speed, and indeed at least comparable with the P-51D and Spitfire XIV.
From the German point of view, trying to equal the P-51H and the similar with jets (and then some) would've been a much better bet . We can recall that jet engine pre-date the DB 603L and Jumo 213E by more than a year - a huge time period for the ww2.
Without the GM1 in picture, the Fw 190D with Jumo 213F (low-drag airframe + low-drag engine) was probably the fastest among the piston-engined fighters for the LW, even if we don't believe in the 760 km/h mark.



As the OTL 190D was.


1700 PS for take off for a 109 was more than was needed. The much heavier P-51D was with under 1500 HP for take-off.
The 605L already required C3 and MW50 (75 L/h) for 2600 rpm and 1.43 operation, due to the very high compression ratio (8.5:1 or 8.3:1)and no intercooler. It needed 150 L/H of MW50 for 2800 rpm and 1.43.
What could've been done is slashing the CR down to 6:1 (as in the Merlin), or at least keep it under 6.5:1. Lower CR = greater boost is possible = greater power. Trade-off will be a slight loss of power at high altitudes, that I see as a good deal.
Intercooler would've helped, but it will require additional volume for radiator, and spare volume on the 109 was at a premium.


The central weapon placement was perhaps a consequence of the desire to install extra fuel tankage (in bags) between the spars? Thus basically doubling the internal takage vs. 190D-9 for example.

Good call. Ju 86s were behind the curve big time when the shooting started.
On the issue of CR vs boost, i'm not sufficiently knowledgeable in the domain, but can you explain as to a layman why did the germans choose high CR? Recall that boost wise, they had immense problems just to make their engines work at 1.42 ata due to lack of high quality materials and the need to find substitutes. If they adopt a lower CR but a higher boost, would not this problem be even more crippling? The allied engines routinely ran at well over 2 ata (Merlins were running at 1.8 ata in 1940!), while the germans only late in the war got to 1.8-2 ata in OTL.

Re the DB-605L, i reasoned that the lower power would impair climb at low and medium altitudes, not desirable tactically of course, hence my question.
 
Part of Post 140.

Part of Post 143.

Also more He111s in place of the Ju86.

One book about the Luftwaffe that I read clamed that enough material build 1,000 aircraft was left after the Ju86 was cancelled as a bomber and that during World War II someone suggested that it be used to build 1,000 Ju86 trainers to supplement the Ju52/3ms. If that's correct the Luftwaffe could have had 1,000 extra He111s in 1939 in addition to the He111s built instead the Ju86s that were completed IOTL.
I made the point in the past that imo Jumo should have completely abandoned any aircraft diesels, and focus on their Jumo-210/211 and later families. So to get more He-111 they need more Jumo-211 or DB engines to power them, at least part of which can be obtained if they build more Jumo-211s instead of the diesels, and/or DB gets an earlier increase in their productive capacity to build more DB-600/601s. Perhaps Junkers should have licenced He-111s as early as possible so they could have built the 1000 of them mentioned rather than have the materials rotting away in depots.

I note that if what i'm reading is correct Junkers were testing 2-stage (!) superchargers in the early 1930s (see the Ju-49 with L88 engine). In OTL who made the turbos for the Jumo-207, was it them or other company? I do understand that it was easier to put a turbo on a diesel due to lower exhaust temperature, hence the Ju-86P (also for which unfinished conponents were available as detailed above), but if they stop any work on diesels they can still work on turbos, but more importantly, can perhaps focus on 2-stage superchargers. So instead of the Ju-86P, they can perhaps have a Ju-88 based high-alt recce in 1940, either with some two-stage Jumo-211 model, or even turbo, or at least a higher altitude single stage superchargers plus GM-1. Either of these would have been far more valuable as the base for further wartime work, as opposed to the dead end high-alt diesels.
 
IIRC, the DB605L was very late and intended for the Bf 109K-14. Supposedly two were delivered in April 45 but I’ve yet to see hard evidence. It differed externally from the standard K-4 by a pair of wing mounted MK108s and a four blade prop.
 
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