Anyone interested in some intellectual exercise?

Admiral Karanado,

In the final outcome I defer to your orders.

I think I concur with several of your recommendations, Sir. The Akizukis would be preferable to repeat Yugumos. I had forgotten that we had drawn up plans for a new destroyer type and was merely thinking that the Yugomos represent a good improvement on the Kageros. (I'm a little more familiar with prewar types. Forgive my oversight.)

I could also be persuaded to consider the honorable Prime Minister's substitution of a third fleet CV for two CVLs. I would prefer to find the additional tonnage necessary somewhere other than the CAs, though. We have a great many CAs, but not all are equally effective, and the Tone class CAs are extremely useful scouting platforms. I would very much like to have more of them available to attach to another strike force. We could conceivably do away with the CLAAs entirely and simply use conversion to fill that need for now. Alternately, we could combine scouting and AA into a new CLAA design based on Tone.

As to the DE types, I was using Matsu as more placeholder than anything else. They could be useful as a near fleet destroyer, since we do have some slower fleets. Lighter slower escorts could be built at civilian yards, but at the same time, a simpler escort would be fine. However, the Matsu tonnage feels about right, so they're probably a good measure of how many hulls we could produce.

The specific types are all fairly approximate. The ratios were more important.

For minesweepers (and minelayers), tenders, fast transports, landing ships, and other "unspectacular types" I believe we can use civilian yards. I hadn't gotten too specific on civilian shipping yet as it will require time and consideration outside my area of expertise. You're quite correct that we will need more of these than we have. Small fast auxiliaries can be had from converting older destroyer types: Minekazes and Wakatakes for instance. The removal of one boiler from a Minekaze would probably yield a speed close to 30 knots with good endurance and small, but useful displacement. Larger auxiliaries can, of course, be converted from merchant ships or merchant designs.

(If you saw my wargaming fleet you would know that I rather like these "unspectacular" ships. I may well have more of them than anything else save destroyers.)

But the carriers may be our biggest difference. I initially came to the same conclusion as Karanado: our needs for more hulls outweighs our need for a better design. But then I considered the wisdom of our victorious forbears. We defeated the Russians and Chinese not with more ships, but with better ships. We cannot hope to outbuild the Americans, should we find ourselves needing to fight them. We plan to fight the British and not the Americans for now, true, but our building program is a counter to the Americans. If we have four carriers and lose three of them we have one carrier. If we have three and lose one we have two. It seems to me preferable to have fewer more durable, generally superior carriers than many rather inferior types. Never before have we quit building a better design and instead given preference to a less capable one. If we can build a well protected carrier on the displacement of an Unryu then we should do this. I'm not sure this can be done. The decision is yours, but I have come to think that the wisdom that saw us through past conflicts would be well applied here.

 

This is the kind od debate we were looking for, both make great arguements. Well done!

 

most honourable sirs, i would like to propose that the 3 kuma class vessels that have not yet under gone torpedo conversion,be taken in to one of the smaller ship yards and converted to amphibious troop carriers, the main batteries would be removed, and only the secondery batteries would be retained, the ships could be gutted and a new bow which would allow troops to disembark could be added,these changes would allow these ships to be much faster, probabaly even getting an extra 6-10 knots. these ships would not be gunfighters, they would, if found by an enemy force, pop smoke and run. these ships if converted would roughly hold 2 bns. of infantry each.

 

I suspect the newer maps wouldn't be useless as the old roads and railways are likely still there. The problem would be that so are newer ones and many of the older ones may have been upgraded. So useful with a bit of caution.

Thanks for the offer but I'm not sure I have the time that this calls for or that I would like to put into it.

Considering the likely opposition and resource constraints wouldn't light tanks be a possibly more effective solution. Likewise how much AT capability is needed prior to say 1943?

 

as far as the map MAtrix games has a very good pacific war game.

 

S Poet,
Thank you for all of your great ideas. Could you refer me to this wargame fleet that you mention? Appreciatively, Rikanaga.

 

Given that the "secondary battery" amounted to all of two 8cm guns, they could provide neither an adequate AA defense for the ship, nor any meaningful fire support against any enemy opposition. "a new bow which would allow troops to disembark could be added," sound like a bow similar to an LST, or similar landing craft, this would be at odds with the "high speed" you expect. Further, the light cruisers had roughly a 29-30 foot draught, which means that they will not get anywhere near a beach to unload their troops. Also, the weight loss you propose will likely be somewhat offset by the weight gain of modifying these ships as troop carriers, and their cargo of troops and their equipment. Not to mention that the horsepower needed to achieve high-speeds increases dramatically, so I doubt you will see a 6-10 knot gain in top-speed, even without the new bow.

I would also add, is this conversion really necessary? Once we have achieved our objectives in the South Pacific, how many more invasions are we contemplating that will require the use of such large high-speed transports.

 

Related to that is that one of the problems the Japanese had in WWII is they pushed their perimiter out past their ability to support. Even with imporvements in their log system there are definite limits as to how much they can support. Beware of over extension.

 

Mine Warfare Craft

It is my understanding that mine warcraft need not be either large or particularly fast. If this is correct, is it practical for us to field such vessels from non-strategic materials such as wood as much as possible? If so then could not they be fabricated in civilian shipyards rather than those commited to heavy warship construction?

Oilers, Tenders, Repair, Replenishment, Amphibious Ships

It is also my understanding that these ships have a great deal in common with traditional merchantship construction. Most should be able to be built in civilian yards, the exception may be underway Oiler/Replenishment units that might need greater speed than the others.

I would submit that we build these ships from our merchant fleet budget until at least we find ourselves at war with the US. While I realize that we would produce fewer merchant hulls in the near term, I feel that both our plans to engage only European powers at first and in conjunction with a greater effort towards convoy and ASW assets, we will see a greatly reduced loss rate among our existing merchant fleet. This factor combined with hoped for increase in resources reaching the Home Islands may just compensate for any reduction in numbers for as long as our main battle fleet can keep the US Pacific Fleet at bay.

High Speed Assault Transports

Such craft are tempting, but are they practical for us considering the type of war we plan to wage? Our initial amphibious operations will occur without any new ships of this type as we will need time to either convert or build them. They might possibly be ready should we need to execute such attacks on American possessions like Wake, Guam and the Phillipines after the securing of the SRA.

If this occurs after say January 1, 1943 these targets will be deep within our area of operations and we could approach from any point of the compass, staging quite close to our objectives. Is there then any great need for speed in these ships? We also have no intention of further amphibious operations either closer to the US mainland, Australia or the Indian Ocean. A small number of such types of ship seem a luxury we can ill afford.

I would need a better understanding on how and where we would use such craft before I can offer my support for thier aquisition.

Next Generation Fleet Carrier

this is what I can find on short notice,

Type: Shokaku Tonnage: 26,000 Aircraft: 72 Range: 7,600 miles Construction time: 4 years (peacetime)

Type: Taiho Tonnage: 30,000 Aircraft: 65 Range: 10,000 miles Construction time: 3 years

Type: Unryu Tonnage: 17,000 Aircraft: 63 Range: 8,000 miles Construction Time: 2 years

Shokaku class is undoubtedly our best designed CV, Taiho most expensive, and Unryu our best bargain. 3 Unryu's for the cost of 2 Shokaku's and ready far sooner.189 aircraft against 145. If there is better data please advise.

PM

 

"Mama, the navy guys are getting all the sources!" Hope the CV´s will get a good safety belt by destroyers and submarines?!

 

I feel your pain, what I know about the IJA would make a readers digest seem well informed. Then again we have our best man on the job so I have no worryies!

 

Thank you much! I hope i´m as good as you are thinking that i am! ......but if not, the equipment was the problem and the tanks and the soldiers and.........

 

thats okay, the first line in my memior's goes "... if it wern't for my pigheaded Admrials and Generals...

 

Am i lucky to be a Field Marshall!

 

For now...For now..

 

Just so every one is on the same page, the tonnages are roughly correct for standard displacement of each class.

Aircraft numbers will vary according to source. "Warships of the Imperial Japanese Navy 1869-1945" gives Shokaku as 84, Taiho as 60, and Unryu as 65.

"Warships..." also gives the ranges as 9,700nm @ 18 knots for Shokaku, and 8,000nm @ 18 knots for Taiho and Unryu.

Construction time for Shokaku was roughly 4 years, for Zuikaku it was reduced to 3 years, 4 months.

 

Even if fabricated of steel, they can, and I believe should be built in smaller civilian yards. The vast majority of them were built with "merchant scantlings" which is to say lighter civilian structural standards. (Even when not armored, warships have more and heavier frames, more compartmentalization, and double or triple bottoms. They're much much stouter ships. They use more steel and it shows.) Small minesweepers, and even small and midsize merchants could conceivably be made of wood or even concrete. (Believe it or not.) Concrete has some significant disadvantages that would have to be overcome, it's quite brittle and it wicks up water, but even in the last war the Americans made merchants of both. For now, however, we can probably use steel since the expense of building the infrastructure to make concrete canoes and plywood boats would probably be prohibitive. (And I'm not sure we have a good source of that much wood without invading and stripping New Guinea.)

Even fleet oilers are essentially converted tankers. The additional fittings required are more or less all above the main deck level, so it's no problem at all to fit them. Just additional hoses, pumps, and valves, really. And AA and (sometimes) directors and communications and radar if you can get it. Virtually all of our auxiliaries will be built to civilian standards and should be built in civilian yards. They are, after all, auxiliaries, not combatants. No need to put armor on a truck. Indeed, it would be so cost prohibitive you won't have enough trucks.

We will need such craft for resupply, reinforcement, and evacuation of forward positions. At the very least New Guinea and the Solomons will be objectives we will wish to consider. We might also consider Vanuatu, Fiji, and Western Samoa. (Since Vanuatu is presently a condominium of the British and French we could conceivably occupy it just to "protect" French interests from the British.) Any and all of these could form a barrier between the U.S. and Australia. Even if the U.S. is officially "neutral" they have a nasty habit of supporting one party over the other. We might desire to interdict that. And it will be good to have the capacity to get out fast.

I can't believe we couldn't build a Shokaku at least as quickly as Taiho. Since we've already got all the plans and jigs to build two simultaneously, we should really be able to build follow on units much more quickly. I can see the argument for building Unryus, but I'd think two and a half to three years would be a much more realistic build time for follow on Shokakus. If we lay down additional Shokakus now I'd guess we should have them available by mid to late 1943. We could conceivably build three or even four at once, since we have five shipyards large enough to build them, each with multiple graving docks of adequate size. (Kawasaki, Kure, Mitsubishi, and Yokosuka, and possibly also Sasebo, which converted Kaga.)

Now, we don't want to build carriers at the expense of all else, but we have the capacity to build quite a lot of them if we need. Even relatively good ones. The real bottleneck will be training airgroups, and we're working on plans to improve that. However, whatever design we choose, we should plan to build at least four of them in either one or two programs, and possibly as many as eight in two programs. (I would hesitate to tie up more than four docks at once with carrier construction. We can afford that, but perhaps not much more.)

We need to conduct a careful survey of available graving docks at our yards capable of military construction and plan our programs accordingly. Capital units will tie up a large dock for two to three years. Smaller units will require less build time, and could be built either many to a dock or at smaller docks. And we will want to keep perhaps a third of our docks open for routine maintenance and heavy repairs. (This is just a guess.)

If Admiral Takao or another member of the council has the information close to hand I would humbly request it. Otherwise I shall attempt a survey and I will disclose the results as soon as they are ready.

Sincerely,
Admiral Noka

 

Please, let us not speak in terms of subordinating some persons' ideas to others, at least until we need to make a definitive decision. While I like to think that my concepts are fairly well thought out, I am submitting them to the group for discussion and decision, hopefully by consensus.

If we can build a well protected carrier on the displacement of an Unryu then we should do this. I'm not sure this can be done.

I think you are correct. The rationale for moving from the Hiryu to the Shokaku design was largely protection, although there was an increase in aircraft complement also. If time and resources were not critical, the Shokaku might be our preferred design. I think we have defined the choice; at this point I would like to hear from our comrades.

While I appreciate Bobimoto-san's information, I cannot but think that Taiho's construction time faster than Shokaku's must reflect wartime urgency, since she is a larger and more complex ship.

No offense, Takao-san, but light cruisers with a draft of 29 feet? More like 16, although that still makes them unattractive candidates for a 'new bow which would allow troops to disembark'. Fast transports based on light cruisers or destroyers might be better off carrying Daihatsu landing craft; the Americans have converted six of their WWI-era destroyers to APDs with landing craft in davits. If we do anything along this line, we could remove the ships' torpedo tubes and enclose the area where they were mounted to provide additional accommodations.

 

Also, an aside:

Is there an etiquette distinction between salutes and likes? I've not quite grasped the latter yet and thus haven't used them often.

 

None taken, thanks for pointing out my mistake, I was looking at the hull depth in Lacroix & Wells and took it for the draft.