Anyone interested in some intellectual exercise?

OK, an important question here, we are already up to 1,000 posts, and it's getting a little difficult to have BOTH a strategy discussion and the building/weapons discussion on the same thread.

Would anyone object if we had a separate thread to analyze the political/strategic options?

I would be willing to make a summary and give some input on various options & drawbacks that have the different options have, but it would be better (IMHO) to have it on a separate thread so that you dont have to go back a half dozen pages to find the posts that are relevant.

 

And now we have the 1000 Post in this Thread! Not that bad! Seen to late that you´ve mentioned it freebird.

 

My source, www.history.navy.mil/library/online/japaneseshiploss1.htm

Much more there.

A bit more for thought

Japanese Merchant losses Dec 1941-Dec 1942

Month/Number of ships/Tonnage/(Tankers)

12/41 12 57,700
01/42 17 73,800
02/42 09 37,200
03/42 20 103,100 (2)
04/42 09 42,800
05/42 24 105,100 (1)
06/42 10 38,500
07/42 12 62,300
08/42 23 114,300
09/42 14 54,500
10/42 36 177,000
11/42 30 168,200
12/42 25 88,300

Total Hulls lost: 241
Tonnage Lost: 1,112,800

Tankers Lost: 3 (a little over 1% of total losses)
Passenger-Cargo: 65 (27% of total losses)
Ferry's/Converted warships(gunboats/armed merchants), Tenders, etc: 26 (10+% of total losses)
Cargo/Transports: 147 (61+% of total losses)

Ships lost to British/Australian/Dutch/Unkown(some with American collaboration): 19 (-8% of Total Losses)
Ships lost by Japanese action (Mines/Marine Accidents): 27 (11+% of total losses-1/3 mines, 2/3 Marine accidents)
Ships lost to American action: 195 ( 80+% of total losses)

There would be no 'Tanker Shortage' in 1942, even if a worst case scenario (at war with America from start).

We are a greater hazard to our merchant fleet than the Dutch/British Commonwealth!

 

The idea isn´t bad to have two threads! It would be much easier to discuss the topics on seperate threads.

 

The Dutch supply guessing 30% of the tankers that ship our oil and of course they will not be available, so that is where the shortage comes in.

 

I fully agree.

 

From USS Langley - First Aircraft Carrier USS Langley it looks like they took two years converting the Langley to a carrier and 6 months from carrier to sea plane tender. I suspect you could build CVE's from scratch either faster or almost as fast as you could convert them especially if the conversion was not planned when the ship was built.

 

I have it virually completed just need to double check facts and finish proof reading, Unfortunately real life is consuming more of my time lately. I told you back in post#782 on March 25th that the older son was deploying:

I told someone I don't remember who that I couldn't tell where he was going because of OPSEC but would tell once he was there (haven't even managed to get that done yet). Anyway because of taking care of his affairs, needing to and wanting to provide moral support for his fiance who's dad was hospitalized (he'll be O.K.), having to put extra time in at work because one of our guys is out, ending up having to work last weekend and this one, etc., my time available to finish up has been limited. Anyway, after I get off tommorrow I can hopefully finish up.

AFRICA is the answer to where he deployed:

 

The Japanese began using arresting gear almost from the very beginning. Among other things, Hosho tested numerous longitudinal and transverse arresting systems before setting on a British transverse system. This same system was installed on Ryujo at the time of her construction in the early thirties. Even while still using relatively light biplanes the IJN used arresting gear. In the absense of clear evidence that she didn't have it I continue to believe it is quite safe to assume that she had arresting gear from her initial conversion. But in any case, it's a moot point. We are quite familiar with the technology and can install it on any ship we feel might need it. (Such as any carrier we might wish to use to train aviators to make carrier landings. There's really no reason to train them to do anything else.)

A CVE of 28 knots with an air wing of 20 would certainly have more capabilities than a MAC of 20 knots with 6 aircraft. No question about it. A Porsche 911 has more capability than my little old Hiroshima built Miata, but I wouldn't necessarily say that it would be "better" for me. Depends on what I need. And I'd say the Miata more than meets my needs and I've better uses for the other 95 grand or so. IF what we're doing is looking to provide a little airborne ASW to a convoy I would argue that the CVE really ISN'T better. The MAC gives us what we need on a fraction of the price tag. And it can haul something. Definitely better IF we want airborne ASW in lots of different places and don't have the U.S. Caviar budget. If Amphibious ops are more important then we want the CVE. As it happens, I want both, but I want more MACs and fewer auxiliary carriers of one kind or another. (How many amphibious assaults are we likely to make after 1942? How many convoys will perhaps need protection from subs? How many from aircraft? How many from surface ships?)

1.) I'll leave the construction times aside for now. I'll have better information on that in a few days. But I will say, the 4-5 month in figure is quoted for conversions. It wouldn't necessarily take so much longer as all that for a new build MAC. The cargo capacity would be somewhat less on a hull of roughly the same cost. There is no free lunch. But we ought to be able to get the construction difference to less than that on new build.

2.) I'm not sure what you mean by building a CVE deck at the same time.

3.) As to the CAM ships, that's a very good question. A real possibility.

I'm skeptical that the very minimal conversion we're suggesting would add anything like 30-50% to the cost.
Land based air cover will certainly be a useful part of our ASW operations. A CAM ship of sorts might serve us well, but since we're not worried about shooting down enemy aerial spotters, I don't think we need the aircraft fitted to the catapult to be a high performance land based sort. A seaplane (great, more seaplanes) might serve us just as well or even better. And it could potentially land and be taken back aboard. We've discussed using seaplane tenders. This might be a better option. Cheaper even than MACs, but offering some of the same benefits. And this conversion would take virtually no time at all. Just clear some space at the fo'c's'le and bolt the cat to the deck.

1.) We could possibly include a small hangar. Britain did so on the grain ship conversions. We'll need some of those to bring rice from Indochina. While Britain didn't find it practical to include a hangar on the tanker conversions, we intend to use larger faster tankers. (500'+ 19.5 knots.) We could conceivably fit a very small hangar somewhere since we'll have more deck space to play with. It might make loading or emptying the tanks less efficient, so it could well affect loading time, but it would get aircraft out of the weather. That said, while typhoons are a significant concern around Japan and the Philippines, particularly as you pass from the Westerlies into the Trade Winds, they're virtually unheard of as you go farther south into the warmer and stiller air of the doldrums where our SRA lies. A note: the South Pacific is that portion of the Pacific south of the equator. A very small minority of our operations will take place there. The Java Sea and Banda Sea are in the South Pacific. The South China Sea and Celebes Sea are not. Even Singapore is still north of the equator. (Though not by much.) We can, however, refer to our area of operations generally as the "Western Pacific."

2.) We're discussing ships carrying perhaps six aircraft. A dozen of them would have a compliment virtually identical to one large fleet carrier. Wear and tear should be less since the aircraft are not high performance and operations will be less intensive. The number of mechanics required will likely be much less than on a fleet carrier. Since the aircraft will be few and light deck handling can likely be carries out by the ships own company. No real need for additional deck personnel. Since Japan doesn't use an LSO anyway we shouldn't need any special personnel beyond flight crews and mechanics, and possibly an extra communications officer aboard ship. Can't see why excess aircraft would be jamming up flight decks on MACs. That's really only a phenomenon of carriers in battle attempting to land aircraft from other damaged or destroyed carriers. There probably won't be any aircraft nearby beyond what the MAC came with, and all of those will fit.

You raise some valid questions, but I don't think typhoons or conversion cost will likely rule against using MACs in lieu of CVEs. Lets do some testing at Kure or Sasebo first and see what happens, but I think a few MACs should be a simple and inexpensive expedient. (15 at the VERY MOST. Probably fewer. No need for dozens to protect the limited number of convoy routes we're considering.)

 

Actually the Dutch submarines will be your primary threat, they have about 18 - 20 in the DEI and that was their primary base.
The British had very few subs in the East at first, and the US are mostly firing dud torpedoes.

If you missed my earlier post, HazeGray clearly states that they did not have them, I provided the link (besides the fact that it seems it was installed in 1943.)

Quite true.

Keep in mind, when I say "cost" I refer only to the shipyard time, as actual cost (in yen) is irrelevant.
It seems that the US took about 12 - 15 months to build a freighter prewar, and Japan about 15 - 18 months.
Conversions took about 6 - 10 months, with the US slightly shorter, and the British rather longer.
I was doing a rough calculation that 6 - 8 months to convert into a carrier is 30% to 50% of the 15 - 18 months to build a standard freighter

I will be very interested to see what numbers you come up with for construction time.

Indeed, the typhoons would be mainly a concern if operating beyond the Bismarck sea, however the monsoon rains would be more frequent and still a problem for ops in the South China Sea. I would think that a small hanger would be a very good idea.

I was thinking if the deck-parked aircraft had serious mechanical problems, or were damaged in a storm, it would be inconvenient to have to leave them above deck, while you tried to continue operations.

Well I guess if you did put a hanger in it is almost a CVE rather than a MAC anyways.

 

No Problem, Bob! Do it if you have the time to do. Live runs often in a different direction!

Hmm, not a fine place to be!

 

Using the data I posted earlier Non-American Allied sinkings amounted to 19 ships for all of 1942, certainly an acceptable number and about equal to ships lost to "Maritime Accidents". It is indeed tempting to say forego convoys altogether until a US DoW, but when we go to war with the US losses rise dramaticly, so I advise we begin conoys as soon as practicle to gain the training and expierence for when we need them.

 

There are AMC that carry 1 or 2 aircraft so maybe look at them for enlarging

 

Although honestly, for the Japanese to use the numbers from 1942 in their forward planning would be completely unrealistic, wouldn't it?
And the Japanese also had some big help from crappy US detonators on the early torpedoes, which isn't something they could have predicted

With respect my American friend, the worst case scenario isn't war with America right away, it would be if the Allies had made an effort in the PTO similar to that in the ETO.

I would suggest that the most realistic plan would be to use the data from Italy & Germany for 1939 - 1941, about their losses and the capabilities of the Allies - and to plan accordingly.
Now, if the Allies have a much weaker effort against Japan in 1942 - good for Japan! But at least they will be ready if the Allies go full throttle, instead of the half-assed effort they did make in 1942.


I found some data posted on Axis History forum here: Axis History Forum • View topic - German Merchant shipping?
Some of it was originally posted here: WWIIdaybyday.com which unfortunately is in German.

Here is the data I found for German losses, in: A) initial number of ships B) number built, C) Losses, & D) total at end of year:

V Large >7000ton Merchants
1939 : 167 + 8 -10 = 165
1940 : 165 + 5 -24 = 146
1941: 146 + 1 -33 = 114

Large 5000-7000 ton Merchants
1939 : 148 + 8 -10 = 146
1940 : 146 + 1 -41 = 106
1941: 106+ 2 -19 = 89

Medium 3000-5000 ton Merchants
1939 : 184 + 11 -10 = 185
1940 : 185 + 0 -24 = 161
1941: 161 + 2 -33 = 130

So Germany lost 44% of it's 5k - 7k freighters and 37% of it's 7k+ freighters by the end of 1941.
Those kind of losses would be a disaster for Japan.

These are the causes listed for the whole war:

604 ships totalling more than 660,000 tons to mines laid by the RAF/RN
289 ships totalling more than 574,000 tons to air attacks from the RAF's Coastal Command.
104 ships totalling more than 314,000 tons to RN submarines.
86 ships totalling more than 303,000 tons to RN suface ships (including MTB's )

Here are two further links provided about Axis losses:
In German: Chronik Seekrieg 1939-1945
In Italian: http://www.regiamarina.net/merchant/intro_us.htm

So what I would suggest (IMHO) is if Gebirgsjaeger could check the data in German, and perhaps if ToS (the Italian representative) could give some data on Italian losses, and post it here. That would be most likely what data Japan would have to plan with, as well as data from the U-boat campaign
What I'd look for in the German loss data: was it a similar % in 1939 - 1941 as it was for the whole war? (ie: mines, aircraft, subs, & ships)

 

I can do it with a little work! Dang, the German lost in 1939 205.224tons of merchant ship room!(SP?)

 

Freebird much of the data in this thread is post war and not entirely what a person of the period would know, but short of a lobotamy this is something we cannot entirely escape.

I will argue an American legal concept of "Inevitable Discovery". Japanese leaders could infer that shipping losses to non-American forces would be fairly limited by the understanding that we would quickly dislocate Dutch air/sea forces from their home bases with all that entails, and by the limited resources available to the British due to her commitments in Europe.

 

axis mechants losses med in 1940 186,000 1941 714,000 1942 522,000 1943 767,000

 

It should be what you strive for in planning though.

Not really until you have a year or more experience at war.

I wouldn't just blindly assume that the US would be the most dangerous opponent and all other ineffective, the US havn't had a couple of years at war to train & test their forces.

Well, the Dutch have been fighting with Britain & Commonwealth for over a year, so I'd argue that it's safe to assume that they will have prepared to use bases in Singapore, Australia, Fiji, Ceylon or wherever. The DEI isn't able to procuce torpedoes AFAIK, so the Dutch subs are already supplied by the British in 1941

I belive that in fact the Dutch were the most effective sub force for the first 6 months or so, despite the loss of the DEI.

Well, let's look at that:
During 1941, the RN has eliminated a big chunk of the Axis naval threat in Europe, and is no longer worried about a German invasion of Britain (as the LW & army are busy in the USSR). They have a large number of longer range older bombers (Hampden, Whitley, Wellington etc) that are being replaced by more modern bombers (Stirling & Halifax), and are training a huge number of aircrew, so there is no reason why they couldn't send some of the older bombers to the PTO to begin mine & patrol operations there.
The Australians & Canadians are also producing bombers (Beaufort, Hampden & Bolingbroke) which could be used for this purpose.
(I don't know if Japan knew about Australian production in 1941, but Japan shouldn't just assume that they couldn't, as IIRC they knew Canada was producing bombers & fighters)


Australia also has a large number of aircraft & trained aircrew in the MTO, Japan would certainly assume that in event of hostilities in the Pacific that they would all be recalled to fight the Japanese.
(The fact that many didn't until later in the conflict is more a result of poor British planning than lack of ability.)


So there really is no major commitment in Europe in the second half of 41 that would prevent Britain from sending significant numbers to the Pacific, to begin mine and/or maritime attack operations.
They have a commitment to send material to the Soviets that will tie up shipping resources, but that wouldn't affect their ability to send air assets to the Pacific.

Again, setting aside what we know did happen as a basis for plans, the Japanese should look at what they could have done, with the info they had at the time and try to prepare to counter it.


Suppose for example that you are playing Axis air war in Europe. You know (hypothetical) that in 1942 the RAF had a major attack against Stuttgart in May, and Hamburg in June, but didn't attack Dresden at all. If your oponent was using the exact historical playbook, you could send all your flak to Stuttgart, then after the attack move it all to Hamburg.

This would be the best defence, however it's completely unrealistic. (even if you argue that they might have done that)
The most realistic way would be to put 1/3 of the flak in each of those cities, even if you know that said city will not be attacked.



Bottom line: IMO Japan should prepare to meet all manner of threats to it's shipping, be it ship, mine, sub or air attack, and prepare defences for them all.

 

You are correct, we wouldn't be using data from 1942, we would be looking at it from a military perspective. I will elaborate on that later in my reply.

With respect to our friend in the colonies, worst case scenario is war with America. All the allies put together, without the US and Russia, do not have the excess military power to seriously challenge us unless they decide to pull back in the ETO, Med and North Africa. Russia at the present has its hands full with Germany's invasion. They all feel Germany is the primary threat and they will not and cannot pull resources from those areas. America has a strong navy but will lack the capability to mount an amphibious counter-attack for close to a year from now.

That data, other than the fact that submarine campaigns can be very effective is largely irrelevant to our situation because the basic conditions faced by them are so different from those we face. What we do need information on, and to study is not numbers, but tactics we need to determine which offensive tactics are most effective and which counter-measures cause the most problems. We can do this by having our intelligence people debrief German U-Boat commanders. We refine our own doctrine by determining what works best for the Germans offensively and decide how to counter that. We determine from these captains which of the allied counter-measures give them the most heartburn and further develop them.

We have determined we are planning for a long war, in this case we will adapt our offensive submarine and defensive, anti-submarine doctrine with that strategy in mind.

Yes they would, but our situation is so different, primarily due to geography that the two are really not comparable. I would also submit that if we can shape the battlefield effectively, allied merchant shipping losses could actually cripple them.

Several members have already addressed this but, here goes again. If we properly shape our battlefield, mines will be of little concern for sometime, the allies will lack the ability to sow the mine fields also, mine fields deteriorate rather quickly if they are not maintained or replenished. Air attack initially will be of little concern because allied air bases will be located too distantly for their aircraft to reach our most important shipping lanes because they lack the range. A ship attempting to reach those areas would most likely be sunk and even if they reached the area they would likely lack the fuel to get back. Initially, subs are their only method of counter-attack, their carriers can raid but even they would have a hard time surviving to hit our major shipping lanes. We can use geography to severely diminish the British ability to operate submarines against us. The Dutch, even if we failed to sink most of their boats initially will quickly become ineffective due to lack of fuel, lack of provisions and lack of torpedoes. They will have no bases to operate out of. That leaves the US. We hope to avoid war with them for sometime, this will give us the opportunity to build our defenses against submarines.

 

Japan had a very effective intelligence network and knew allied capabilities in the region. You underestimate Britain's available military power. After the Pearl Harbor attack one of Britain's biggest fears was that it would draw off American military support. If Britain was in such good shape, why didn't she send the assets to Singapore that the British commanders there requested? Why did the US have to send some of its fleet to help out in the Atlantic when the situation became so desperate in the Pacific? The US surely needed the Wasp and Washington in early '42 in the Pacific but they were sent off to operate with the home fleet, why?