AHC: the best possible Luftwaffe for 1940

Deleted member 1487

At work.

Am quite enjoying the thread.

Much interesting information and points of views being presented.

Just a question. Given the OP's comment of kickjng things off in 1936......

What sort of butterflies might be needed for something like the Do 335 to be thought of and/or developed?

Or is four years not enough time?

Cheers.
For starters you'd need ejection seat technology to move up quite a bit lest the rear props do so nasty things to bailing out pilots.

The below is from the book "Dornier Do 335 'Pfiel'" by Heinze Nowarra.
The genesis of the Do335 goes back to the Do18 flying boat with tandem engine layout, which was a 1936 design and in 1937 he patented the concept that led to the Do335 and started working on the technology. When he proposed it as feasible in 1940 the concept was rejected by the RLM, but Dornier still built a proof of concept aircraft, the Gö-9. Apparently once that was fully tested Dornier worked on a family of aircraft with the tandem engine layout, which was ultimately cancelled in 1943, but replaced with spec for what became the Do335 and the work was folded into that project and got Hitler's endorsement to make it a priority project, which yielded the first prototype for testing in late 1943 (October or so).

For a realistic POD Dornier would have develop the technology sooner and get the RLM interested in funding it as a high priority project, but given the engineering challenges, I don't really see how it could be ready before 1943 even as a high priority project as of say 1939 when the proof of concept was started. Short of ASB there is no way to even start the project in 1936 due to all the basic research that needed to be done first to even demonstrate the idea was workable for a military aircraft.
 

JAG88

Banned
The Ju89 needed major changes to the fuselage as well due to the low bomb load capacity, since it was only 1600kg, less than that of the He111. Unless you want to just mount bombs externally. The wing would also have to change and would the cockpit.

The Ju89's fuselage was 3m tall and 2,5m wide if the scale of the drawings ir correct, they had plenty of space for bombs and fuel so modifying it shouldnt be much of an issue even if forced to use ESAC type racks. You can always improve the wing, but "have to", why? Not long ago the ju90 was supposed to be an improvement, now we clearly see it wasnt.

What is the issue with the cockpit? And pretty much ALL LW bombers modified it during their service...

The Ju290 was quite a bit different than the Ju90 in all the above areas.

Yeah, and was worse for it.

Of course the Ju90's changes made the military performance worse, because it was designed around civilian luxury transport needs. The engine used was only marginally more powerful until the Jumo 211F (a 1943 engine btw) or Double Wasp engines (American engines that weren't available in wartime) were added, but note that the empty weight went up substantially as did the loaded weight with passengers. Look at the max start weight too, that was quite a bit higher for the Double Wasp model vs. the Ju89. The civilian model was set up for something substantially different than the light loaded Ural Bomber design.

I am comparing V3 vs V5 same fuselage, but new wing on the latter, the wing that replaced the Ju89 wing, weight difference in both gross and MTOW is a paltry 130Kg... You do realize that the Double Wasp-equipped ones used the old Ju89 wing, right? Meaning that it shows what the Ju89 could have done with better engines in spite of the bulkier and draggier Ju90 fuselage, it does nothing to prove the new wing was better, on the contrary, plus, the Ju89v2 had already lifted more than that with its crappier engines.

The "light loaded" Ju89 managed to lift a 10t payload to 9.000m...

The Ju290 had to mount bombs externally, as the converted version was a military transport that was shoehorned into the long range recon role with bombs attached much like the Fw200 (it was adapted from the civilian version for the Japanese as a long range naval recon aircraft right before WW2 and ended up in the Luftwaffe when they were cut off from Japan).

I seriously doubt the numbers are for aircraft with external loads... and the Fw200 carried its bombs internally either in the gondola or engine nacelles.

The Ju89 had potential of sorts, but needed major redesigns to get there. A 189 using the experience and work on the Ju89 would have been just fine. The problem though is that Junkers, who designed it, was tapped to make a huge number of fast bombers, the Ju88, which absorbed their capacity to make aircraft especially given that they also made the Ju87. So they weren't really in a position to make a large four engine bomber. That's why the RLM went to Heinkel to make the Bomber A/He177 as a replacement for the aging He111, as it was intended to have excess capacity, while Dornier then made a 'heavy' multipurpose twin engine bomber, the 217.

Oh, the Ju88 "problem" has a fix... :biggrin:

As to maneuverability the Lancaster was actually pretty maneuverable and at night was agile enough to get out of the way of night fighters if it spotted them. The HE177 was also quite agile for it's size (even before the dive bombing requirement was added it was intended to be able to dive at a shallower angle), which meant easier handling in the air for the crew; not having that meant it would be much more exhausting for the crew to try and maintain and adjust in the air, especially during climbing and landing (nothing like stalling while trying to land), not to mention to get into formation and deal with unexpected situations where it would need to rapidly maneuver itself. Obviously it wasn't comparable to a single or twin engine aircraft in terms of maneuverability, but having the ability to be stable in the air when going through maneuvers was very important for any aircraft in combat at least according to Eric Brown, British test pilot who flew more aircraft over a longer period than maybe anyone else in history, including both British and German aircraft (he got to test out all the nifty Luftwaffe designs at the end of the war and wrote a book about it, "Wings of the Luftwaffe"). He even reported on the FW200, Ju290, and He177 and compared them to the British and American heavies. He does note that maneuverability in the air for heavy bombers isn't necessary so long as they have heavy defensive firepower to keep fighters off of them, which the militarized Ju290 did have. Apparently though the Ju290 did have better handling for rapid maneuvers to get into cloud cover in a tight spot than the Fw200 and even landed on a shorter strip than the 200.

Do you have a source on the Ju89 maneuverability, agility or lack thereof?
 
At work.

Thank you indeed for the reply.

So.... instead of the 'Push-pull bugger to bail out of' what about something like the Ki-64?

Same engines..... just work on a different radiator lay out other than the He-100 clone on/in the wings.

Cheers.
 

JAG88

Banned
For starters you'd need ejection seat technology to move up quite a bit lest the rear props do so nasty things to bailing out pilots.

Or just cut/blow up the rear shaft/propellers...

The below is from the book "Dornier Do 335 'Pfiel'" by Heinze Nowarra.
The genesis of the Do335 goes back to the Do18 flying boat with tandem engine layout, which was a 1936 design and in 1937 he patented the concept that led to the Do335 and started working on the technology. When he proposed it as feasible in 1940 the concept was rejected by the RLM, but Dornier still built a proof of concept aircraft, the Gö-9. Apparently once that was fully tested Dornier worked on a family of aircraft with the tandem engine layout, which was ultimately cancelled in 1943, but replaced with spec for what became the Do335 and the work was folded into that project and got Hitler's endorsement to make it a priority project, which yielded the first prototype for testing in late 1943 (October or so).

For a realistic POD Dornier would have develop the technology sooner and get the RLM interested in funding it as a high priority project, but given the engineering challenges, I don't really see how it could be ready before 1943 even as a high priority project as of say 1939 when the proof of concept was started. Short of ASB there is no way to even start the project in 1936 due to all the basic research that needed to be done first to even demonstrate the idea was workable for a military aircraft.

Well, there was an even earlier one...

Dornier P.jpg
 

Deleted member 1487

Or just cut/blow up the rear shaft/propellers...
The Do335 did that too, but apparently that wasn't enough, which is why the did the ejection seat as well.

Well, there was an even earlier one...

View attachment 466888
No, that is a very different sort of design than the Do335, which had the engines in the fuselage with the pilot in between. Entirely different engineering task that was apparently quite difficult to pull off.[/QUOTE]
 

Deleted member 1487

The Ju89's fuselage was 3m tall and 2,5m wide if the scale of the drawings ir correct, they had plenty of space for bombs and fuel so modifying it shouldnt be much of an issue even if forced to use ESAC type racks. You can always improve the wing, but "have to", why? Not long ago the ju90 was supposed to be an improvement, now we clearly see it wasnt.
What was it all filled with though? Fuselage dimensions don't really tell you a whole lot.
Also the Ju90 was supposed to be a civilian transport, not an improved military aircraft. Totally different role.

What is the issue with the cockpit? And pretty much ALL LW bombers modified it during their service...
Visibility.

Yeah, and was worse for it.
How so?

I am comparing V3 vs V5 same fuselage, but new wing on the latter, the wing that replaced the Ju89 wing, weight difference in both gross and MTOW is a paltry 130Kg... You do realize that the Double Wasp-equipped ones used the old Ju89 wing, right? Meaning that it shows what the Ju89 could have done with better engines in spite of the bulkier and draggier Ju90 fuselage, it does nothing to prove the new wing was better, on the contrary, plus, the Ju89v2 had already lifted more than that with its crappier engines.
The Ju90 used their wings for a different purpose.
Also the V3 and V5 versions had different start powers and service ceilings, but the same cruise HP. I forget if Kraftstoff means fuel, but the V5 has more of it and probably had a higher fuel consumption to achieve it's higher starting power.

The "light loaded" Ju89 managed to lift a 10t payload to 9.000m...
It was a stunt to show it was possible and helped lead to the transport version of the aircraft. That says nothing about the fuel consumption to get there, range, speed, handling, etc.

I seriously doubt the numbers are for aircraft with external loads... and the Fw200 carried its bombs internally either in the gondola or engine nacelles.
I don't think you understand what 'internal' means...
The bombs on the nacelles were on external bomb racks. The bomb gondola was an external bomb bay grafted on to the bottom of the aircraft with observer stations to allow for accurate bombing, as the cockpit was not actually set up to have a good enough view for bombing plus have ventral defensive gun points.

Oh, the Ju88 "problem" has a fix... :biggrin:
Not making it I assume? So what do you replace it with?

Do you have a source on the Ju89 maneuverability, agility or lack thereof?
Any aircraft with a payload several times beyond the design spec is not going to handle well. Per your chart 2500kg was their normal limit.
 

JAG88

Banned
No, that is a very different sort of design than the Do335, which had the engines in the fuselage with the pilot in between. Entirely different engineering task that was apparently quite difficult to pull off.
[/QUOTE]

True, but I was talking about the Do 18 inspiration, and there were even earlier ones I think.
 

Deleted member 1487


True, but I was talking about the Do 18 inspiration, and there were even earlier ones I think.[/QUOTE]
Sure, like the Dornier Wal, but in the book the 18 is cited as the design that inspired Dornier to try and put a pilot in between the engines.
 

MatthewB

Banned
The dependence on twin engine medium and light bombers never made any sense to me. It’s akin to RAF Bomber Command using Blenheims, Hampden and Whitneys throughout the war.
 

JAG88

Banned
What was it all filled with though? Fuselage dimensions don't really tell you a whole lot.
Also the Ju90 was supposed to be a civilian transport, not an improved military aircraft. Totally different role.

Yep, but didnt you claim the Ju89 required a lot of effort to finally make a usable aircraft in the form of the Ju290?

An airliner would have been concerned with economic cruise range overall, and yet that got worse in spite of the extra fuel.

If you have a large volume available it is easier to move and shift things around, I doubt it had crossbeams and pillars inside...


Visibility.

?

Ju89 cockpit2.gif


And, still, the LW always made changes in service and in this case no reason for them to not make changes to the prototype.


It kept growing and growing, requiring more powerful and scarce engines and fuel to the point of being way too expensive beyond a niche and specialized role.

The Ju90 used their wings for a different purpose.
Also the V3 and V5 versions had different start powers and service ceilings, but the same cruise HP. I forget if Kraftstoff means fuel, but the V5 has more of it and probably had a higher fuel consumption to achieve it's higher starting power.

Yes, its fuel.

It has more fuel and STILL less range, same engine, different variant, same cruise PS, weight is about the same so I would actually blame the new wing.


It was a stunt to show it was possible and helped lead to the transport version of the aircraft. That says nothing about the fuel consumption to get there, range, speed, handling, etc.

Still managed to do it, meaning you have a nice 10t payload for the bombload/range equation, and did so with 900PS engines, it would have entered service with 1200PS Jumo 211s before moving on to 1400PS ones.

I don't think you understand what 'internal' means...
The bombs on the nacelles were on external bomb racks. The bomb gondola was an external bomb bay grafted on to the bottom of the aircraft with observer stations to allow for accurate bombing, as the cockpit was not actually set up to have a good enough view for bombing plus have ventral defensive gun points.

I do... do you?

The gondola was an addition but still part of the aircraft, as were the turrets and other protrusions, but yeah, the 2 bombs behind the outer nacelles were semi-recessed but external.

Not making it I assume? So what do you replace it with?

Oh, that one is for another time and falls outside this scenario anyway.


Any aircraft with a payload several times beyond the design spec is not going to handle well. Per your chart 2500kg was their normal limit.

So no source.

For the underpowered prototype, yes, but the aircraft had a huge 180m2+ wing for lift, which is why it managed the feat, and stronger engines in the pipeline to address the issue.
 

JAG88

Banned
The dependence on twin engine medium and light bombers never made any sense to me. It’s akin to RAF Bomber Command using Blenheims, Hampden and Whitneys throughout the war.

It makes less sense when you know that Kesselring told Goring that they could make 3 twins for the cost of two 4-engine bombers...
 

JAG88

Banned
I see your point.
I tried to propose limited, reasonable improvements as to the basic Luftwaffe's mission, the doctrine, the way of thinking, the strategies, and, eventually, very small improvements in the nuts and bolts too. I did not go very far because yes, it would have defied suspension of disbelief in Nazi Germany. Anyway, it's in the first chapters here:
https://www.alternatehistory.com/forum/threads/a-better-show-in-1940.103866/

I am reading your TL, very interesting stuff so far.

Edit: Ok, I am suing you, you clearly hacked my computer and read my stuff!!! :biggrin:
 
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For starters you'd need ejection seat technology to move up quite a bit lest the rear props do so nasty things to bailing out pilots.

The below is from the book "Dornier Do 335 'Pfiel'" by Heinze Nowarra.
The genesis of the Do335 goes back to the Do18 flying boat with tandem engine layout, which was a 1936 design and in 1937 he patented the concept that led to the Do335 and started working on the technology. When he proposed it as feasible in 1940 the concept was rejected by the RLM, but Dornier still built a proof of concept aircraft, the Gö-9. Apparently once that was fully tested Dornier worked on a family of aircraft with the tandem engine layout, which was ultimately cancelled in 1943, but replaced with spec for what became the Do335 and the work was folded into that project and got Hitler's endorsement to make it a priority project, which yielded the first prototype for testing in late 1943 (October or so).

For a realistic POD Dornier would have develop the technology sooner and get the RLM interested in funding it as a high priority project, but given the engineering challenges, I don't really see how it could be ready before 1943 even as a high priority project as of say 1939 when the proof of concept was started. Short of ASB there is no way to even start the project in 1936 due to all the basic research that needed to be done first to even demonstrate the idea was workable for a military aircraft.
But it only took Fokker 1 1/2 years to go from nothing to a first D.XXIII prototype intended as a combat design, with no previous development airframes whatsoever (design started in early 1938). So what caused Dornier to take 7 years to do the same work from early tandem design to first combat design prototype?
 
But it only took Fokker 1 1/2 years to go from nothing to a first D.XXIII prototype intended as a combat design, with no previous development airframes whatsoever (design started in early 1938). So what caused Dornier to take 7 years to do the same work from early tandem design to first combat design prototype?

Good question. That's why I like this forum.
 

Deleted member 1487

But it only took Fokker 1 1/2 years to go from nothing to a first D.XXIII prototype intended as a combat design, with no previous development airframes whatsoever (design started in early 1938). So what caused Dornier to take 7 years to do the same work from early tandem design to first combat design prototype?
For starters it used an engine with half the power of the DB601, so the engineering challenges were considerably less. The Gö-9 was prepared in even less time and tested for years. The Fokker was also a test bed prototype that still had a ton of problems to work out:
https://en.wikipedia.org/wiki/Fokker_D.XXIII
The trial flights identified problems with the cooling of the rear engine and general engine performance. It was proposed to use Rolls-Royce or Daimler-Benz engines in the production aircraft.[1] Concerns were also raised about the pilot clearing the rear propeller if he had to bail out and an ejector seat was studied.[1] As a provisional solution, rails were put on both sides of the forward fuselage for the Fokker test pilot, Gerben Sonderman, to use to bail out in an emergency. The aircraft was flown 11 times for a total flight time of less than four hours. The rear fuselage paneling was modified significantly before the last few flights in an attempt to address chronic rear engine cooling problems. On the 11th flight in April, the undercarriage was damaged, and the programme was abandoned in May 1940 when the German forces invaded the Netherlands.[1]

They had a LONG way to go before it would have been ready for production and combat use.
 
The Fokker was also a test bed prototype that still had a ton of problems to work out:
https://en.wikipedia.org/wiki/Fokker_D.XXIII
They had a LONG way to go before it would have been ready for production and combat use.
That's true, but I wasn't comparing it to the time for the Do-335 to be ready for production and combat use; I was comparing it to the time to build the first Do-335 prototype (which I assume had a bunch of problems to work out as well). It still took a lot less time.
 
OTL Twin-boomed Fokker DDIII used a pair of almost stock engines. It was easy to balance because the rear engine was just aft of the centre of gravity and the rear propeller was easy to mount slightly aft of the wings’ trailing edge.

OTOH Dornier 335’s more conventional configuration required a long drive shaft to balance the airplane. Long, light-weight drive shafts are complex engineering challenges with a variety of vibration problems that can reduce them to scrap metal in seconds! Long, tail-rotor drive shafts really only became practical after helicopters converted to - much smoother - turbine engines.
Long drive shafts also suffer when subjected to heavy G loads during aerobatics.
As for ejection seats ..... the first production ejection seats were installed in Heinkel Uhu night-fighters and saved the lives of several crew members during the later years of the war.
 
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