Japanese elektroboote

[Rubicon]

Reading up on the Japanese submarine force during WW2 and I came up on this little nugget.

So what if instead of only implemented the lesson very late, the Japanese implement them earlier and on larger subs.

So lets assume that designs on a new submarine begin in the middle of -40 and take about two years with construction beginning in the middle of -42 with another year until they are completed.

That would give the Japanese navy a new type of very dangerous subs by middle/late -43, though with the usual teething problems with new vessels, early -44 would be more realistic.

It wouldn't be a war-winning weapon, but it wouldn't definently cause casulties on the US Navy.

 

[mack8]

Indeed, but for that they really need to adopt tactics more in line with the possibilities of such a sub (no line abreast static picket lines and other such mistakes), and indeed said tactics (which btw, i need to study myself, ie german U-boat tactics) for all their subs regardless of what type. They can perhaps sink several times more opposing ships than in OTL for the same losses.

 

[sloreck]

The problem with Japanese subs was not so much what they were but how they were used. They could be much more effective if they had a different (anti-shipping) doctrine. Even with that the problem was that the shipbuilding capability of Japan was limited. If Japan went to a "U-boat" doctrine, while that would be a more effective use of their subs it would also mean more losses. What does Japan not build in order to make more subs? The Kriegsmarine devoted the overwhelming majority of its shipbuilding resources to U-boats and the Japanese can't do that even if they want to to. They need to still have some surface navy as well as merchant ships.

 

[alexcoppo]

It could have been an interesting possibility if some Kriegsmarine officer had had an extensive tour of No. 71 and reported back to Berlin. The development of OTL Type XXI could have started around 1940 and operational in 1942 with the foreseable effects on the battle in the Atlantic.

 

[CalBear]

As is usually the case with this sort of question, all it takes is for the IJN to throw out four decades of strategic and tactical thought, adopt an entirely different world view, and defy everything they ever learned about naval warfare.

They do all that and it could be a problem, not in insoluble one, but a problem.

Worth pointing out that this was a low endurance, poor habitability, experimental set up. Had they been pursued without the IJN tossing out everything from Admiral Toga onward, they would have been used for defense of the Home Islands, along with Truk and maybe Okinawa. What they represented would have been a tactical challenge, thanks to their underwater speed, but less of one than might be imagined.

They did not have snorkels (those had to wait for the very late war Sen Taka (I-201) class. Had the IJN somehow managed to come up with practical snorkel designs earlier their sub force would have been more formidable, this can, however, be extended to every combatant state that used submarines.

 

[Rubicon]

As is usually the case with this sort of question, all it takes is for the IJN to throw out four decades of strategic and tactical thought, adopt an entirely different world view, and defy everything they ever learned about naval warfare.

I'm quite aware of that, to make Japan dangerous you'd have to start right about after the battle of Tsushima.

I'm just curious of peoples opinions of the strategic and operational difficulties of using elektroboots in the pacific.

 

[CalBear]

I'm quite aware of that, to make Japan dangerous you'd have to start right about after the battle of Tsushima.

I'm just curious of peoples opinions of the strategic and operational difficulties of using elektroboots in the pacific.

Well, these weren't electroboots. They were well streamlined conventional SS, without the most important feature, the snorkel. That gave them better speed, but they had poor endurance, so they are not useful in long range operations, something that is almost a base requirement for operations in the Pacific. The boat itself was tiny, 11 man total crew, a coastal boat, at best.

Even the much later Sen Taka boats were too low endurace of deep Pacific patrols (would have run out of fuel if they tried a round trip to Hawaii from the Home Islands, and would have had about five days if patrol time if they came out of the Marshalls).

In a way they are interesting, being almost a WW II version of the Soviet Project 705 Lyre boats (aka: Alfa class). An underwater interceptor or point defense boat, but lacking all the other features necessary to make a suitable ocean going boat.

 

[I want to learn]

The problem with Japanese subs was not so much what they were but how they were used. They could be much more effective if they had a different (anti-shipping) doctrine. Even with that the problem was that the shipbuilding capability of Japan was limited. If Japan went to a "U-boat" doctrine, while that would be a more effective use of their subs it would also mean more losses. What does Japan not build in order to make more subs? The Kriegsmarine devoted the overwhelming majority of its shipbuilding resources to U-boats and the Japanese can't do that even if they want to to. They need to still have some surface navy as well as merchant ships.

I don't know if attacking merchant shipping is the best strategy for Japan. They're not going to starve the United States into surrendering. Using subs as adjuncts to the fleet basically worked out. They sank Yorktown, Wasp, Indianapolis, Juneau, and Liscome Bay, and damaged North Carolina, Ramillies and Saratoga twice.

 

[Gudestein]

As is usually the case with this sort of question, all it takes is for the IJN to throw out four decades of strategic and tactical thought, adopt an entirely different world view, and defy everything they ever learned about naval warfare.

They do all that and it could be a problem, not in insoluble one, but a problem.

Worth pointing out that this was a low endurance, poor habitability, experimental set up. Had they been pursued without the IJN tossing out everything from Admiral Toga onward, they would have been used for defense of the Home Islands, along with Truk and maybe Okinawa. What they represented would have been a tactical challenge, thanks to their underwater speed, but less of one than might be imagined.

They did not have snorkels (those had to wait for the very late war Sen Taka (I-201) class. Had the IJN somehow managed to come up with practical snorkel designs earlier their sub force would have been more formidable, this can, however, be extended to every combatant state that used submarines.

It could have been an interesting possibility if some Kriegsmarine officer had had an extensive tour of No. 71 and reported back to Berlin. The development of OTL Type XXI could have started around 1940 and operational in 1942 with the foreseable effects on the battle in the Atlantic.

I like this aspect of the WI actually. The Germans seeing somebody working on this could lead them to take it up, and a submarine that is build for being submerged... Maybe they would have used the Snorkel concept for this kind of boat and they knew this already.