How "not" to use submarines

[Rich46yo]

Its interesting that with all the interest in the Pacific war , and the IJN, one reads and hears so little about the IJN submarine force. They started the war with the largest submarine force in the world both in numbers and diversity. Many of their boat designs were very large with incredible ranges, perfect for pacific war.

They had several terrific torpedo designs. One of which, the Long Lance, was the best torpedo in the war. But they also had a very good electric design.

While they had some early success the IJN boats just didn't do a whole lot in the war. The few American capitol ships they sunk and damaged just didn't mean much in the big picture as American shipbuilding Industry kicked in.

The question then is "why didn't the IJN deploy their submarines in a manner that would more influence the war"? History should have taught them that the submarine was far more effective as a weapon against ocean commerce then as a weapon against capitol warships. IJN boats 184 enemy merchant ships, compared to German U-boats sinking 2,840, Yank boats sinking 1,079, Brits boats 493.

Could things have turned out differently if the IJN submarine force used different tactics?

 

[syscom3]

Because the mindset (and doctrine) of the IJN was for the submarine forces to whittle away at an enemies warships.

Commerce raiding was not seen as a glamourous job nor needed in a "short" duration war.

Of course once they saw the need for commerce raiding, the war had progressed to the point they needed their subs to attempt to sink enough US warships as possible before their whole empire collapsed.

Things in the Pacific in 1942 would have been a tad different if the IJN patrolled the coasts off of Mexico, Panama Canal and in between the US mainland and Hawaii.

 

[Njaco]

I was gonna ask if there were commerce lanes west of hawaii. Thanks Sys. Maybe all they had were warships to contend with.

 

[syscom3]

I was gonna ask if there were commerce lanes west of hawaii. Thanks Sys. Maybe all they had were warships to contend with.

You had the sea lanes from the US and Australia too.

Theres a lot of open water south of hawaii that could also have been patroled to great effect.

Imagine if all of the available 4 heavy and medium bombers had to be deployed as sub hunters. The IJA might have held onto NG and won at Port Moresby.

 

[Njaco]

Gotcha, I'm not great on the ETO and even less so in the PTO.

 

[Rich46yo]

Yes and then there was that. This Australia question. Australia was like the Britain of the South Pacific, the unsinkable aircraft carrier. In hindsight it seems strange the Japanese overlooked the place, and I know there were a few in the IJN and IJA that were proponents of invading Australia. But they were not listened to.

Instead the army garrisoned many strategically worthless South Pacific islands that MacArthur was all to happy to bypass anyway. My point being is that military thought by the Japanese high command seemed to lack strategic vision. And strangely in the area of submarine warfare it ignored the lessons of WW-l when German U-boats were extremely effective at hurting England.

Sometimes it just makes you wonder what in heck the Japanese were thinking back then. They did have great strategic thinkers in their high command ; They just weren't listened to enough. I think syscoms comments are very correct in that sinking commerce was considered "to lowly" for Japanese warships. They seemed obsessed with the "win one glorious victory" style of warfare instead of just plain winning the war.

They felt the same way about using warships to convoy commerce ships as well. And it wouldnt surprise me if the IJN looked down on submarine crews and the boats themselves. Really, in retrospect, the war? the way they fought it? it was a waste of a fine navy.

 

[Wildcat]

Imagine if all of the available 4 heavy and medium bombers had to be deployed as sub hunters. The IJA might have held onto NG and won at Port Moresby.

Come on Sys, 4 engine heavy bombers and medium bombers didn't save Port Moresby. It was Australian Kittyhawks and infantry at Milne bay, Australian Militia on the Kokoda track and the USN at Coral Sea that saved Port Moresby. Though Allied mediums and US heavy's played an important part in attacking Japanese troop movements and supply lines, they alone did not save Port Moresby.

 

[Wildcat]

Yes and then there was that. This Australia question. Australia was like the Britain of the South Pacific, the unsinkable aircraft carrier. In hindsight it seems strange the Japanese overlooked the place, and I know there were a few in the IJN and IJA that were proponents of invading Australia. But they were not listened to.

The Japanese did launch a submarine offensive against Australia with mixed results. They did manage to sink allied shipping, but not to a scale or intensity that really hurt allied convoys or brought Aust. to its knees. See this Wiki (!) page for some background info.Axis naval activity in Australian waters - Wikipedia, the free encyclopedia

 

[Lucky13]

So what the Japanese should have done, was to take a page or two from the German submarine doctrine? Taking up the wolfpack tactics....

 

[syscom3]

So what the Japanese should have done, was to take a page or two from the German submarine doctrine? Taking up the wolfpack tactics....

More than a few naval officers at the German embassey in Tokyo were saying that!

 

[Haztoys]

And the IJN had a mess of subs too...Do some home work on it ..Big subs to carry planes ...Cargo subs to move goods ..Real small subs ..Attack subs..Lots of subs...And never used them in a useful way..The war would of been different if they had of...The Germans sure got there money worth out of there subs...

It seems to me that the ego of the Japanese would not let them change a path once they were set...And would not let them do things that the Germans said to do...Every move thay made was some BIG "show"...

 

[Lucky13]

Should have kept it to two types maybe...ocean going and slightly smaller to keep around in the South China Sea and Western Pacific around the islands...

 

[Rich46yo]

So what the Japanese should have done, was to take a page or two from the German submarine doctrine? Taking up the wolfpack tactics....

Even worse then all this, this question of doctrine, the IJA insisted on garrisoning many strategic worthless Islands, which MacArthur was more then happy to bypass, and they did so without a real plan to keep these fortified outposts supplied should a resurgent USN appear. Or forget "resurgent". The seeds to their eventual problems were sown when they didnt attack the USN submarine assets at PH. Again and again the Japanese high command seemed to underestimate the impact submarines could have.

In the end they had to use their submarine force to keep these garrisons supplied, or at least partially supplied. Imagine that? Using submarines to keep an army supplied? I just hope they didn't bring an appetite.

So they were basically gofer's for the IJA. And they paid the price anyways because by 1944 the American navy had become a fearsome submarine hunting navy. My point of course is the IJN submarines should have been deployed doing something useful.

Would it have changed the war? I dont know but I do know our commerce fleet was heavily stressed in the first few years of war by the U-boats. That, and the Pacific was light on DDs due to the Atlantic U-boat threat.

So one has to assume in adopting a meaningful battle doctrine for their U-boats the IJN would have had a bigger impact. In that era U-boats really shined when attacking merchant shipping. I know they sunk some capitol ships but when you compared the losses between the two the WW-ll submarine was over matched when up against capitol warships. Especially later in the war when sonar, radar, and escort CVs became the norm.

"Most of all" IJM boats which werent as maneuverable as German U-boats due to their size and couldnt dive as deep due to the quality of steel used in their construction.

 

[Lucky13]

The Japs and the German's were probably bosom buddies well before the war started. Maybe they should have copied the Type IX subs...

 

[Glider]

The IJN had the subs to create all sorts of problems for the US it was their approach to using them that was a missed oppertunity. They had the range to attack almost anywhere on the US West coast. This alone would have caused the US to spread their forces across half the Pacific, leaving weak spots.
The Japanese also had enough submarines to launch co-odrinated attacks on convoys using similar wolf pack tactics. There is a lot of ocean between the US and the pacific bases and it could have been used to effect.
A small point about the Japanese using submarines to resupply the army bases on the islands. The IJA had their own submarines for resupply, hard to believe but true.
Also the Japanese subs could dive quite quickly the earlier ones were a little slow but considering their size it was quite good and the later ones were very handy.
As for the diving depth, no submarines could match the Germans in this area so there is no shame in not matching them.

 

[Lucky13]

Was there any island that were suitable to build advanced u-boat bunkers or bases?

 

[Wildcat]

Singapore?

 

[Lucky13]

Must have been a few places suitable for this....

 

[Rich46yo]

Sorry Ive been away from this for awhiles. I wonder if there also wasnt some other dynamic at work regarding the IJNs failure to achieve much with a capable boat force.

Its know IJN subs showed little success even when operating in heavily traveled commerce lanes, most of all later in the war. I know they were also restricted by their command staff, most of all in using torpedoes. But so were USN commanders, PH itself once went bingo of torpedoes available.

The Japanese High Command was traditionalist and extremely hierarchical in structure. The same for the IJN. I wonder if submarines weren't look down on on a navy where the surface force, most of all the heavy platforms, held the power? The reports of morale problems in the IJN boats would appear to support this conclusion wouldnt it?

I would also say the IJN structure frown on individual commanders showing initiative on their own. This would be a fatal flaw in submarine doctrine. USN commanders were given great leeway to develop battle plans. Indeed this was/is probably the greatest strength of western Militaries.

 

[syscom3]

The IJN had lots of success's in 1942 when the subs were on the lookout for US warships.

The Yorktown, Saratoga and Wasp were all victims to the subs (sunk or damaged).

The problem was in their doctrine. Attack the capital ships and dont hunt the merchant men.

As for advanced bases..... Singapore, Kwajelein and Truk and Rabaul all had the anchorages or facilities on hand to be major forward depots.