A6M - Germany Japan Technology Exchange Missed Opportunity?

[NevadaK]

Greetings All,

Reflecting on a number of recent threads in the Forum featuring extended discussions about long range escort fighters, Luftwaffe bombers capabilities, early Spitfires, Hurricanes and Zeros, it occurred to me that one of the missed opportunities of the Germany Japan Technology Exchange was that it appears Japan never shared the design of the Zero at a time when the design of a long range fighter could have been useful to the Luftwaffe, prior to the Battle of Britain. Even if Japan had shared design details, I don't believe it would have altered the path Germany took. It would have required a suspension of the bias the Nazis had against non-German engineering as well as a massive improvement in the Nazi procurement system for the Luftwaffe to benefit. That said, I would be interested in your thoughts about a German advancement of the basic Zero design pre-Battle of Britain? To me, there are a number of obvious questions:

1. Who would be selected to advance the design? Heinkel seems like an obvious choice given the effort put into the HE 100D
2. What power plant? The BMW 801 is quite a bit larger and heavier and would require an entire new airframe. The Rhone-Gnome?
3. How much weight would be aded to the airframe for armor?
4. Would the Luftwaffe even understand the value of a long range fighter?

Your thoughts?

 

[tomo pauk]

This is perhaps better suited for the 'What-if' forum.

(yes, we'd have a blast discussing this, at least Shortround6 and myself are sharpening the respective keyboards...)

 

[NevadaK]

This is perhaps better suited for the 'What-if' forum.

(yes, we'd have a blast discussing this, at least Shortround6 and myself are sharpening the respective keyboards...)

Greetings Tomo,

I debated where to post this. If the moderator would like to move this over to the "What If?" forum I wouldn't object.

Kk

 

[FLYBOYJ]

Done

 

[tomo pauk]

Cheers, Joe

Greetings All,

Reflecting on a number of recent threads in the Forum featuring extended discussions about long range escort fighters, Luftwaffe bombers capabilities, early Spitfires, Hurricanes and Zeros, it occurred to me that one of the missed opportunities of the Germany Japan Technology Exchange was that it appears Japan never shared the design of the Zero at a time when the design of a long range fighter could have been useful to the Luftwaffe, prior to the Battle of Britain. Even if Japan had shared design details, I don't believe it would have altered the path Germany took. It would have required a suspension of the bias the Nazis had against non-German engineering as well as a massive improvement in the Nazi procurement system for the Luftwaffe to benefit. That said, I would be interested in your thoughts about a German advancement of the basic Zero design pre-Battle of Britain? To me, there are a number of obvious questions:

1. Who would be selected to advance the design? Heinkel seems like an obvious choice given the effort put into the HE 100D
2. What power plant? The BMW 801 is quite a bit larger and heavier and would require an entire new airframe. The Rhone-Gnome?
3. How much weight would be aded to the airframe for armor?
4. Would the Luftwaffe even understand the value of a long range fighter?

Your thoughts?

1 - Probably Heinkel - MTT has their hands full with a lot of designs 8both viable and not), Fw has the Fw 190 in pipeline, Junkers is not making any fighters at all. On the other hand, Zero was a reasonably streamlined aircraft already.
2 - Pre-BoB means the DB 601 is the best alternative, basically do what Italians did with MC.200 into MC.202. BMW 801 is too late.
3 - A lot - talk extra 500+- lbs for powerplant, and another 100-500 lbs (depending wht gets protection - self-sealing tanks also weight a lot).
4 - They have had long-range fighters well before ww2 started. But Bf 110 was not what Germany needed for the BoB.

 

[Admiral Beez]

Greetings All,Even if Japan had shared design details, I don't believe it would have altered the path Germany took.

Three things Japan desperately needs in technological exchange with Germany:

1) A strong radial engine to allow for fighters with superlative performance AND protection (armour, self sealing tanks) and heavy armament (with good magazine loads)
2) Shipborne radar
3) Aircraft radios resistant to electromagnetic interference.

Problem is, what technology can Japan offer Germany?

Greetings All,I would be interested in your thoughts about a German advancement of the basic Zero design pre-Battle of Britain? To me, there are a number of obvious questions:
4. Would the Luftwaffe even understand the value of a long range fighter?

If the Germans want a long range fighter they can simply add the later Bf 109G's greater internal fuel and drop tanks. I suspect the German reviewers would reject the Zero outright for its flimsy construction, tiny armament and ammunition load and lack of both a working radio and any pilot or fuel tank protection.

 

[NevadaK]

Three things Japan desperately needs in technological exchange with Germany:

1) A strong radial engine to allow for fighters with superlative performance AND protection (armour, self sealing tanks) and heavy armament (with good magazine loads)
2) Shipborne radar
3) Aircraft radios resistant to electromagnetic interference.

Problem is, what technology can Japan offer Germany?
If the Germans want a long range fighter they can simply add the later Bf 109G's greater internal fuel and drop tanks. I suspect the German reviewers would reject the Zero outright for its flimsy construction, tiny armament and ammunition load and lack of both a working radio and any pilot or fuel tank protection.

Greetings Adm Beez,

In the time frame referenced, 1939-1940, the difference between the Zero and the Me 109E is not that great. There's also a commonly held belief that the Zero didn't have radios. The original design brief included radios as well as RDF. To my thinking, the LW certainly could have learned from the Zero, especially with regards to range and duration something single engine LW fighters lacked.

 

[GrauGeist]

The A6M was far from flimsy, it was vulnerable to gunfire because of it's lack of armor or self-sealing tanks. Otherwise it was quite rugged.

In regards to Germany using Japanese technology, Heinkel had aircraft engineers in Japan for most of the war as well as military attachés, so they were aware of what Japan had and weren't too interested in what Japan had to offer.

Japan needed the long range aircraft because she was a maritime nation and vast distances were often part of their operational criteria as opposed to European aircraft which (initially) didn't require such ranges.

As it happened, Germany did posses a fighter that had nearly double the range of the Bf109E: the He112, however the Germans preferred to stay with the Bf109 because they felt the Heinkel was redundant.

 

[Admiral Beez]

There's also a commonly held belief that the Zero didn't have radios. The original design brief included radios as well as RDF.

They had radios. They just didn't work. Radio Systems in the Early A6M Zero

Insufficient shielding of the ignition system of the aircraft caused interference with reception of signals to a great degree, as did static charges generated by the passage of the airframe through the atmosphere. It seems that there were very few officers at fighter group level who were familiar with radio systems or who cared to conduct effective programs to maintain them. The resulting poor performance quickly led fighter pilots to cease using the radios and resort to the old visual methods. In the case of some land-based groups, they removed all radio equipment to enhance the performance of the planes.

I would argue that the lack of radios contributed to the IJN Zero pilots fighting as individuals as opposed to organized groups. The Luftwaffe definitely has nothing to learn from the IJN about the doctrine of bomber escorting.

 

[Admiral Beez]

3. How much weight would be aded to the airframe for armor?

Per Wikipedia...

A Fw 190 A-8, armed with four 20mm cannons and two machine guns, with a span of 34.5 ft, length of 29.5 ft and powered by an 2,231 lb air-cooled radial BMW 801 had an empty weight of 7,055 lb.

An A6M2 (Type 0 Model 21), armed with two 20mm cannons and two machine guns, with a span of 39 ft, length of 29 ft and powered by an 1,300 lb air-cooled radial Sakae 21 had an empty weight of 3,704 lb.

The Zero is over 3,200 lbs. lighter than the Würger. Of that is nearly 1,000 lbs. of engine, plus heavier engine bracing, ~200 lbs. for heavier armament. Of the remaining 2,000 lbs. we'll find robust German engineering and construction, plus armour, lots of armour, including seat back and sides, bullet resistant glass, and self sealing fuel tanks throughout.

If German levels of pilot and fuel protection are incorporated into the Sakai-powered Zero I'd suggest the Japanese aircraft will be a slug in the sky and lose much of its range advantage. To be fair though, the Fw 190 is not a BoB era fighter... I couldn't find another radial to compare with.

 

[at6]

As for being a slug in the sky, that would be assuming the A6M could even get off of the ground.

 

[GrauGeist]

Why would you compare the A-8 to the A6M2?

A fair comparison would be the Fw190A-1, as it would be a contemporary of the A6M2. The Fw190A-1 had an empty weight of 6,390 pounds


Now, for the Zero to have any survivability in the ETO, look to the A6M5 which was a bit heavier because it had pilot armor, bulletproof windsheild and a CO2 fire suppression system. The mainwings skin was thickened to give it better performance, such as dives and It was also equipped with the Type 99 125 round belt-fed 20mm cannon. The A6M5's empty weight was 3,920 pounds.

 

[Shortround6]

Airframe weights are not going to be identical.
It has little to do with "robust German engineering and construction" and a lot to do with if you want a fighter capable of not breaking when doing a 6 G turn or pull out an 8,000lb plane needs a strong (heavier) structure than a 6,000lb plane.

The Curtiss Hawk series went from around an 800lb wing on the P-36/early Hawk 75 to over 1100lbs on the later P-40s. Put that P-36 wing on an 8500lb P-40 and you save 300lbs. Now trying a high speed dive with a 6 G or more pullout. No enemy gunfire required. the light wing is likely to fold up.

 

[Conslaw]

The problem of the hypothetical German A6M would be timing. The time Germany needed it most was in the late summer of 1940, the Battle of Britain. This is the same time the first service-test aircraft were being tried out in China, 13 practically hand-built A6M-11s. Until the service-test deployment, even the Japanese didn't know the zero's potential. When would Germany have been able to start deploying either an German-built A6M or a domestic design inspired by the A6M? Perhaps a year and a half? That would be mid-1942 at the earliest. Unless the German Zero was markedly superior to the historical Japanese version, it would have had its hands full with the Spitfire IX, which was first deployed in July 1942. A long-range fighter, even one with vulnerabilities, may have been more useful on the Eastern Front, showing up in places the enemy would not expect.

 

[ThomasP]

Careful about calling the A6M2 a slug, or questioning its ability to get off the ground, just because you decide to add some armour and SSFT.

A standard A6M2 weighed in at ~5335 lbs (clean with pilot) and had a wing loading of ~22.1 lb/ft2. The sustained ROC averaged ~3000 ft/min from SL to 13,000 ft. Speed was ~331 mph at 16,000 ft.

If you use the US/UK ~early-war/1941 standard weight of armor and SSFT, you would add about 150 lbs for armour and about the same for quality SSFT. So the Luftwaffe's He A6-2 would weigh in at ~5635 lbs for a wing loading of 23.4 lb/ft2. The sustained ROC would be ~2775 ft/min. There is no extremely accurate way to estimate the decrease in speed this would cause, but I doubt it would be more than a ~3 mph difference.

While the speed is still low for the ETO, it will still out-maneuver (at low speeds) any other frontline fighter, and out-climb (sustained) all the US fighters of the time, with only the Spitfire, Whirlwind, and Me 109 managing better. Range would be decreased by maybe 20% due to the SSFT installation (down to ~1000 miles on internal) but it would still out-range any ETO single-engine fighter of the time. And since it normally carried a DT that added ~550 miles range, the ROA would end up somewhere between 200 miles clean and 400 miles with DT (ROA would be ~550 miles with DT but limited by decreased internal fuel).

I think I did my math right. I do not know what the normal Luftwaffe fuel allowance was for WUTO, climb, combat, and reserve, so I used ~US/UK early-war standards for the ETO.

If anyone has info on the Luftwaffe standard fuel allowances I would appreciate it if you could post them here or on another thread.

 

[Admiral Beez]

The only thing the Zero offers the Germans in the BoB is endurance. The Germans weren't dumb, if they wanted a high endurance single engine, single-seat fighter they would make one. What the Japanese might do is demonstrate its benefits in time for the Bf 109G's long range to be applied to the BoB era 109E.

 

[NevadaK]

The A6M was far from flimsy, it was vulnerable to gunfire because of it's lack of armor or self-sealing tanks. Otherwise it was quite rugged.

In regards to Germany using Japanese technology, Heinkel had aircraft engineers in Japan for most of the war as well as military attachés, so they were aware of what Japan had and weren't too interested in what Japan had to offer.

Japan needed the long range aircraft because she was a maritime nation and vast distances were often part of their operational criteria as opposed to European aircraft which (initially) didn't require such ranges.

As it happened, Germany did posses a fighter that had nearly double the range of the Bf109E: the He112, however the Germans preferred to stay with the Bf109 because they felt the Heinkel was redundant.

Greetings GrauGeist,

Thanks for your comment. Following your post I did a quick read about Heinkel and the Japanese which I had been unaware of. One thing that struck me was that Heinkel had been working hard to sell the He112 on the world market and Japan was a potential buyer. It appears that after receiving a few units they felt it didn't offer a significant improvement over the B5N and cancelled the order. I might be confusing markets, but I also recall seeing comments that it was perceived as a maintenance burden as well. One could see where some of the Zero's strengths (ease of maintenance, maneuverability) reflect the values of the IJN when it comes to aircraft design.

I agree, Japan realized the need for long range aircraft earlier than most due to the maritime operational criteria. To me, the miss happens when Heinkel or other German manufacturers didn't perceive the value of a long range fighter in the European Theater. The He112 was redundant as it was going after the same market as the Me109 and same limited supply of power plants. Had Heinkel developed the later He100 along the lines of a long distance fighter perhaps they would have found a more receptive market as the need for range and duration became apparent in 1940.

Regards,

Kk

 

[NevadaK]

They had radios. They just didn't work. Radio Systems in the Early A6M Zero

I would argue that the lack of radios contributed to the IJN Zero pilots fighting as individuals as opposed to organized groups. The Luftwaffe definitely has nothing to learn from the IJN about the doctrine of bomber escorting.

Greetings Adm Beez,

Going back to the original point, the Zero had radios, whether they worked isn't the issue. If the Zero as a direct design or as a plan form was developed for the European Theater the incorporation of radios wouldn't be an additional weight burden.

With regards to bomber escort, I wonder how long it would take for the LW to adopt tactics similar to those of the 8th Air Force once they possessed a fighter with adequate range to engage and fight the opponent throughout the theater? Less escort and more aggressive.

Regards,

Kk

 

[NevadaK]

The only thing the Zero offers the Germans in the BoB is endurance. The Germans weren't dumb, if they wanted a high endurance single engine, single-seat fighter they would make one. What the Japanese might do is demonstrate its benefits in time for the Bf 109G's long range to be applied to the BoB era 109E.

Greetings Beez,

One thing that I have been struck by, is the size differential between the Me109 and the A6M. Comparatively, the A6M is quite large. Not only is the wing 7' wider, the fuselage has significantly greater volume which allowed the Zero to carry significantly greater fuel. I don't believe that the Me109 can be made to carry that kind of fuel load in 1940.

Agreed, the Germans weren't dumb, but I believe that they were limited by the same commonly held belief that a long range fighter was impossible that limited most aircraft designers of the day. They wouldn't have designed a long range fighter because they didn't believe it was possible. Its one reason the Zero was such a shock to the west. Two manufacturers were invited to propose a design for the Zero and one, Nakajima, backed out because they didn't believe it was possible. At the very least, the Zero as a design would have provided a road map for a German manufacturer to follow and would have shown that it was possible.

Regards,

Kk

 

[NevadaK]

The problem of the hypothetical German A6M would be timing. The time Germany needed it most was in the late summer of 1940, the Battle of Britain. This is the same time the first service-test aircraft were being tried out in China, 13 practically hand-built A6M-11s. Until the service-test deployment, even the Japanese didn't know the zero's potential. When would Germany have been able to start deploying either an German-built A6M or a domestic design inspired by the A6M? Perhaps a year and a half? That would be mid-1942 at the earliest. Unless the German Zero was markedly superior to the historical Japanese version, it would have had its hands full with the Spitfire IX, which was first deployed in July 1942. A long-range fighter, even one with vulnerabilities, may have been more useful on the Eastern Front, showing up in places the enemy would not expect.

Greetings Conslaw,

Agreed, if the technology transfer had to wait until the service introduction of the Zero, then there is no impact on the BoB. However, with the Zero first flying in 1939 there would have been an opportunity to share design knowledge and as someone else has pointed out if Heinkel representatives had been aware of the development there would have been an opportunity for Heinkel to take the initiative and perhaps rethink either the 112 or 100.

Regards,

Kk