WI: Bf 109K (Kürfurst) in 1942.

[tomo pauk]

The 109K shared the same basic airfrme with the 109F from the late 1940. The Bf 109F1 was already doing 600+ km/h in the winter of 1940/41.
DB 605A was a bored-out DB 601E, that was a development of the 601N, that was again a development of the 601A (DB also worked on the 601C and D, with 2-stage S/C, those were not produced for service use). See here (scroll a bit) FWIW.

 

[Garrison]

No reason? Like I said, Willy Messerschmitt already wanted a replacement for the Bf 109 in 1940 as he feared it would be outclassed by new Allied aircrafts, The Reich Ministry did not in OTL, in TTL they do, but how convoluted and sometines idiotic decisions were made by all sides of the war, they want to use the 109 as the base.
It doesn't fit my premise? The Allies are developing better aircrafts, when the 109 K would appear they would have the P-51D, which is equal to the K-4, at most they will push for an earlier P-51H or F-82.
(Plus, there were instances where solutions to problems were ignored for whatever reason, or infighting happened, so the Allies not developing an uber fighter to outclass the K-4 in all ways when it appears in 1942 is not as unlikely as an Austrian, homeless painter becoming the Fuhrer of Germany)

The Bf 109 in 1940 did not reach its limit, the F and G series are a testament of that.
The K-4 was slightly heavier than the G-6 (100 kgs more or less) but had a more powerful engine. The point of the K was to decrease cost.
(The introduction will reduce production? Yes, as much as the E, F, G did, less than introducing a new design like the Ta 152 or He 177)

Willi Messerschmitt wanted the RLM to adopt some new fighter, and the reason for all the further revisions of the Bf 109 was his failure to deliver. Also the reason Messerschmitt was so keen for a new fighter wasn't strategic, it was economic and political, he didn't want to see his aircraft overshadowed by the Fw 190. There was no strategic imperative in 1940 for the K model, it was entirely the product of having to combat better Allied fighters and the failure to deliver an effective replacement. No one in 1940 was thinking they really needed to replace the F model yet and trying to do so would absorb resources needed elsewhere. There just is no need for the K in 1940, and proposing it would raise awkward questions about why the supposed replacement aircraft wouldn't be able to do the job in the same time frame? To put it another way the K model was the desperate solution to a problem that hadn't yet become apparent in 1940 and if Messerschmitt were gifted with clairvoyance he wouldn't propose the K, he would push the Me 209 sooner, and it would probably be as much of a failure as it was OTL.

 

[marathag]

Rather than saying the Konrad come out early, that a better Gustav is made later instead?
get rid of that fixed tail wheel, larger rudder(light aluminum, not heavier wood) and not so many lumps and bumps, just fix up the aerodynamics than hope for a earlier than expected engine.
leave off the heavy GM system maybe move up the simpler MW instead

Or just to a slight upscale of the 109 to fit the larger DB 603, like a single engine Do-335, so an annular radiator MG151/15 cowl guns and 20mm centerline, and two 20s in the wings
This is built in place of the Me-210, that is spiked in 1940, with the 110 continued production with the DB 605 earmarked for the 210. Send what 210 tooling there was to the Hungrians to play with

 

[Reggieperrin]

To be fair, it wouldn’t be completely insane for someone at the RLM to lose patience, tell Messerschmitt to STFU about the 209/309/x09 and just build the absolute ultimate possible 109 so it can lose vs the 190 and be forgotten about. No crazier than some other stuff they did, anyway.

The technical issues to deliver it seem daunting though, it wasn’t like they weren’t trying hard OTL. However if the RLM and DB and Messerschmitt all suddenly had a freakish outbreak of common sense and cooperation for many months then maybe they could get all their shit in one sock? Such a big departure from normal practice is a teetering tower of low-plausibility changes.

Even if such a hypothetical time-warp beast was somehow built and somehow fielded a couple years early, I can imagine it would twitch some rings among the allies for a while but it doesn’t seem like it would be a completely insoluble problem. If they were desperate, just winding the boost up until their engines have the same average life as german engines and stripping out some weight would probably get them a fair way. Not ideal by any means but the allies weren’t nearly as close to the ragged edge as the Germans were.
And a much-earlier 109K doesn’t seem like an aeroplane that would be deployed in huge numbers with tremendous reliability.

 

[tomo pauk]

Rather than saying the Konrad come out early, that a better Gustav is made later instead?
get rid of that fixed tail wheel, larger rudder(light aluminum, not heavier wood) and not so many lumps and bumps, just fix up the aerodynamics than hope for a earlier than expected engine.
leave off the heavy GM system maybe move up the simpler MW instead

Gustav was already produced as such before the G-5 sub-version: retractable tailwheel is there, no lumps and bumps. It was good for 400 mph even with the de-rated DB 605A. Shortcomings: feeble firepower with just one 20mm cannon and two 7.92mm LMGs. Addition of 13mm HMGs = lumps and bumps. Addition of gondola cannons - same thing, just worse. Same with bigger main wheels, that gave birth to the bump in the upper wing surface so the wheel fits in when U/C is retracted. Rudder was already aluminium. MW 50 needs the DB 605A to be debugged 1st.

What might come in handy is introduction of wheel well covers to improve streamlining by 1942, not in late 1945 with the 109K-4. Also a 'MG 151/25', ie. a 25mm gun with ~200 g M-shell at 750-800 ms, so the necessity for HMGs is lessened. Or a 30mm gun for a 270-280 g shell at 700+- ms, like the Japanese did it (too late, though).

Or just to a slight upscale of the 109 to fit the larger DB 603, like a single engine Do-335, so an annular radiator MG151/15 cowl guns and 20mm centerline, and two 20s in the wings
This is built in place of the Me-210, that is spiked in 1940, with the 110 continued production with the DB 605 earmarked for the 210. Send what 210 tooling there was to the Hungrians to play with

Any Luftwaffe what-if worth reading has the Me 210/410 cancelled ASAP.
A 109 with a really big V12 = Me 209/1943? The DB 603 was a dumpster fire reliability-wise in 1943, and barely better in early 1944.

To me, the real heir to the 'ordinary' Bf 109 is a jet powered fighter.

 

[Nell_Lucifer]

To be fair, it wouldn’t be completely insane for someone at the RLM to lose patience, tell Messerschmitt to STFU about the 209/309/x09 and just build the absolute ultimate possible 109 so it can lose vs the 190 and be forgotten about. No crazier than some other stuff they did, anyway.

The technical issues to deliver it seem daunting though, it wasn’t like they weren’t trying hard OTL. However if the RLM and DB and Messerschmitt all suddenly had a freakish outbreak of common sense and cooperation for many months then maybe they could get all their shit in one sock? Such a big departure from normal practice is a teetering tower of low-plausibility changes.

Even if such a hypothetical time-warp beast was somehow built and somehow fielded a couple years early, I can imagine it would twitch some rings among the allies for a while but it doesn’t seem like it would be a completely insoluble problem. If they were desperate, just winding the boost up until their engines have the same average life as german engines and stripping out some weight would probably get them a fair way. Not ideal by any means but the allies weren’t nearly as close to the ragged edge as the Germans were.
And a much-earlier 109K doesn’t seem like an aeroplane that would be deployed in huge numbers with tremendous reliability.

That sounds amusing. Would it be more of a stretch if Willy was even more insistent about a replacement for the 109 than OTL, annoying and harassing the RLM until they make him to shut up. With the RLM looking at the toy DB is experimenting with (DB 605) and force the two to make the best Bf 109 they can and give up on the damn xyz09 obsession.

To me, the real heir to the 'ordinary' Bf 109 is a jet powered fighter.

In the TL configuration I assume. That is also an interesting alternative, but, when and with what jet engines? Heinkel's? HeS 30 or HeS 40 on a 1942/early 1943 Bf 109 frame?

 

[Garrison]

Gustav was already produced as such before the G-5 sub-version: retractable tailwheel is there, no lumps and bumps. It was good for 400 mph even with the de-rated DB 605A. Shortcomings: feeble firepower with just one 20mm cannon and two 7.92mm LMGs. Addition of 13mm HMGs = lumps and bumps. Addition of gondola cannons - same thing, just worse. Same with bigger main wheels, that gave birth to the bump in the upper wing surface so the wheel fits in when U/C is retracted. Rudder was already aluminium. MW 50 needs the DB 605A to be debugged 1st.

What might come in handy is introduction of wheel well covers to improve streamlining by 1942, not in late 1945 with the 109K-4. Also a 'MG 151/25', ie. a 25mm gun with ~200 g M-shell at 750-800 ms, so the necessity for HMGs is lessened. Or a 30mm gun for a 270-280 g shell at 700+- ms, like the Japanese did it (too late, though).



Any Luftwaffe what-if worth reading has the Me 210/410 cancelled ASAP.
A 109 with a really big V12 = Me 209/1943? The DB 603 was a dumpster fire reliability-wise in 1943, and barely better in early 1944.

To me, the real heir to the 'ordinary' Bf 109 is a jet powered fighter.

Jets were the future, problem was that the German models ran straight in to the major problems that afflicted their efforts all through the war. Pushing to deploy designs that weren't yet ready for combat, material shortages that affected performance and reliability, and of course multiple designs all competing for attention and resources, leading to a number of dead ends being pursued and even deployed.

 

[tomo pauk]

In the TL configuration I assume. That is also an interesting alternative, but, when and with what jet engines? Heinkel's? HeS 30 or HeS 40 on a 1942/early 1943 Bf 109 frame?

1-engined jet fighter for sure. Whether something that looks like the Yak-15 or -17, or a jet-propelled Me 163 (like the P.15 or P.20 designs from Lippsich), or a He 162 with a proper wing (nick the wing from Bf 109 for all I care), or a less ambitious Ta 183 or MTT P.1101. Or the Fw Flitzer.
Engine - whatever can be made. By 1944 we'd probably want the Jumo 004.

Jets were the future, problem was that the German models ran straight in to the major problems that afflicted their efforts all through the war. Pushing to deploy designs that weren't yet ready for combat, material shortages that affected performance and reliability, and of course multiple designs all competing for attention and resources, leading to a number of dead ends being pursued and even deployed.

Trying to go ahead with 2-engined fighter designs without a certain supply of engines was a wrong way to start with.

 

[Finbarr the Fair]

I do like these threads, i learn a lot about which technical possibilities might be open to the various Powers in WW2 (or others). And why they weren't pursued OTL.

I think the initial suggestion is interesting but faces two types of problems. One is why would the RLM give the go ahead and secondly how feasible is accelerating the necessary new engine (or upgrades?). The first ought to manageable but it would take a rare outbreak of far sightedness in German weapons planning. Not ASB but we may have to ask what would be sacrificed to push for resources to be granted to the project. Especially as the technical issues will require resolution

But as a WI, it's fine. However we kind of know the answer. We can see how the British reacted to the introduction of the FW190. Hurried upgrade to the Spitfire and push to get the Typhoon into service asap. At any cost.

The reaction to an early Me-109K will be similar. Different options (Tempest or even the Fury?), dunno what the US can come up with. Plus bomb the shit out of the factories thought to be manufacturing its parts and the assembly line. And with greater resources the WAllies will regain air superiority even with marginally inferior aircraft.

Finally, is the Me109K markedly superior to the 1943 version of the FW190? Would accelerating the development of the latter to the Ta-152 not be better, albeit still difficult?

 

[CalBear]

The best thing the Luftwaffe could do with 109 production starting in 1942 was retool the plants (both airframe AND engine since the DB 601/605* was only used by the Luftwaffe in the 109 & 110/210) and build more Fw-190s. The 109 hit its natural end point with the Gustav, with the Emil arguably the time to put it out to pasture/accept that it was what it was and spend research dollars on the -262.

*The DB 603 production would be something that should be maintained, largely because it was used in a number of non Messerschmitt designs.

 

[tomo pauk]

Finally, is the Me109K markedly superior to the 1943 version of the FW190? Would accelerating the development of the latter to the Ta-152 not be better, albeit still difficult?

The Bf 109K climbs better and it is faster than any Fw 190, even the D-9 (Jumo 213A engine).
Ta-152 needs the 2-stage supercharged Jumo 213E in order to out-perform the competition. The Jumo 213A (1-stage supercharged) is yet to be made by winter of 1943/44.

To me, having a suitable engine is the key.

 

[ric350]

As Greg mentions in those videos I posted above, the biggest issue the G series 109 had was needing to detune the engine due to the lower octane fuels generally available, (plus the Germans never matched the Allied supercharger technology). This is what led the Germans to develop various engine injection boost systems, like MW50, which gave the 109k its good performance. Of course as the 109 airframe was modified (to accept bigger guns, etc), it’s parasitic drag increased as well. No longer the sleek machine the 109F was.

Also as I recall Galland was horrified when the 109F didnt retain the wing guns the 109E had. He reasoned that newer pilots needed a “spray and pray” load out rather than the “sniper” load out of the F and later 109s. I also believe Galland had wing guns installed on his F. Later the wing gondolas were added to the G, with disastrous results.

ric350

 

[tomo pauk]

As Greg mentions in those videos I posted above, the biggest issue the G series 109 had was needing to detune the engine due to the lower octane fuels generally available, (plus the Germans never matched the Allied supercharger technology). This is what led the Germans to develop various engine injection boost systems, like MW50, which gave the 109k its good performance. Of course as the 109 airframe was modified (to accept bigger guns, etc), it’s parasitic drag increased as well. No longer the sleek machine the 109F was.

Unfortunately, Greg in his video about the 109K fails to state some important details. 1st - the 109K-4 was not faster than P-51D. Then - the improvements that cut the drag vs. the late Gustavs are not highlighted, these being less draggy HMG cowlings, retractable tailwheel, and the wheel well covers. These 3 changes amounted to 20 km/h speed gain vs. the G-10 that had the same engine. It is also not mentioned that DB 605D have had the big S/C taken from the DB 603, that much improved the high altitude performance, almost matching the high-alt capabilities of Merlin 60 series.

Also as I recall Galland was horrified when the 109F didnt retain the wing guns the 109E had. He reasoned that newer pilots needed a “spray and pray” load out rather than the “sniper” load out of the F and later 109s. I also believe Galland had wing guns installed on his F. Later the wing gondolas were added to the G, with disastrous results.

Yes, indeed, the armament suite on the 109F was a step back. Me, I'd leave the MG FFMs in the wings, no cowl MGs what so ever, and MG 151/20 firing through the prop.

 

[marathag]

This is what led the Germans to develop various engine injection boost systems, like MW50, which gave the 109k its good performance.

no replacement for displacement, for making HP on the cheap
DB-603
It's 2717 Cubic inches. Bigger than a Griffon and a tiny bit smaller than a Mikulin AM-38 two of the other Big Bore Vees of WWII
Downside it's heavy, just over 2000 pounds, a bit more than those two

But not as good P/W ratio either, from lack of access to the high octane fuels and better supercharger on the Griffon by a large margin, and slightly worse P/W ratio than the AM-38.

But it's an honest 1500, without a lot of boost or water injection, and can be run for long periods of time without overheating the engine, so less need to tear the engine down after running at the high levels of power. Germany just can't afford that anymore, if they really could afford it at all, given the resource and worker situation.

Everyone talks about how bad the turbojets were, but are silent on the teardown work you also had to do with the inlines if ran at WEP for more than a minute
At least the Turbojets were faster and cheaper to build in the first place

 

[tomo pauk]

At least the Turbojets were faster and cheaper to build in the first place

Bingo.

 

[ric350]

Yes, indeed, the armament suite on the 109F was a step back. Me, I'd leave the MG FFMs in the wings, no cowl MGs what so ever, and MG 151/20 firing through the prop.

👍 Do you know the reason the prop mounted cannon wasn’t fitted to the E model? I’ve never seen info on what issues they ran into with it. As I recall that model was supposed to have had one, and the engine was also designed to fit one, which would have given it pretty potent firepower.

ric350

 

[DougM]

Ignoring all the other issues…. This is frankly the wrong choice for the Germans at that time.
At that time Germany was doing good and it was a better idea to design new clean sheet aircraft that ultimately would (in theory) be longer lived have better performance and more room for growth.
It is only with hindsite that we know these designs would not work out and that Germany would be better off going after a better 109 (which was frankly impossible, see above posts for why).

So we have the Germans making a choice that goes against its best interests (with the knowledge it had at the time) simply because history would show it to be a better choice, not for any good reasons at the time
And of course we have them someh advancing design and tech with no understandable way of doing so,
And finally we have the allies proceeding with basicly no changes so whatever caused the two above points will have no result in anyone other then Germany..

Yeah right.

 

[James Ricker]

The 109-K had a more powerful engine that use more fuel that would become a problem
The Me-109K had all the earlier Me-109's poor takeoff and Landing characteristics amplified.
A lot of new pilots and even experienced Pilots are going to be killed in accidents

 

[tomo pauk]

👍 Do you know the reason the prop mounted cannon wasn’t fitted to the E model? I’ve never seen info on what issues they ran into with it. As I recall that model was supposed to have had one, and the engine was also designed to fit one, which would have given it pretty potent firepower.

ric350

Seems that the problem was with DB 601A, that have had reliability issues with the cannon firing. We can recall that there was no DB 601A powered fighter with a prop cannon, be it the Bf 109, Re.2001, MC.202 or Ki-61.

 

[The Wooksta!]

The Kurfurst wasn't a straight development, it was more an attempt to streamline production, pulling all the various G series sub types and add ons into a purpose built airframe. Any 1942 development is just going to look like a Gustav.