Circle Four Building Program

[Elouda]

No problem. I definately support more alternatives. Personally I find the 4 CLAAs and the B64/65 Class from the 5th program the most interesting to add.

I made a personal mod to the Experimental CHS scenario (159) by adding 2 more Taihos(Osumi and Minoo), the B65 Class (Fuji and Chichibu), and the last two Yamatos (Omi and Kii), and changing the Ibukis back into CAs (Ibuki and Iwaki). These all follow historic naming patterns, apart from the CVs as I was really stumped for names. I also added the 5 Montana class BBs to Allied side to mix things up a little - Its not like they need them though. Had a lot of fun playing the AI with this just to see how they change things.

As someone who routinely scraps even Yamato and Musashi to accelerate the Unryu class CVs into mid-43, I find the main problem with late CVs is that you just dont have capable enough airgroups to use them for anything besides raiding - in a standup CV fight, they just get slaughtered.

[Terminus]

I wouldn't worry too much about carrier names. Remember that the Japs themselves didn't bother with "proper" names for the Unryus, aside from the name ship herself.

[Tiornu]

L&W is a great source that goes well beyond cruisers-only. It discusses a lot of general warship construction matters.
The next heavy cruisers after the Tones (including Ibuki) were developed not from the Tones but from Suzuya, even though they were planned to be deployed in the same division with the Tones. Designers didn't even bother trying to juggle the barbettes so all the guns could rest at zero elevation. I see this as a strong indicator of the IJN's verdict on the Tone design.

[John 3rd]

Tiornu--What is L&W? 
 
 

[John 3rd]

I've continued researching and tabulating everything said and see this for the cruiser construction planned:
 
2 CA along the Suzuya-Class
4 CL along the Agano-Class
 
Elouda laid out the DD Classes.
 
It would appear that the Japanese got nearly all the planned DDs finished.  Does that mean they got into the Circle 5 construction?  Was all that planning erased when Midway happened and they radically shifted to the CV expansion program?
 

[Elouda]

Well, as I see it we have, and if theyre in game (CHS) or not;

4th Program - 1939/1940
2 BB Yamato (1 Converted (Shinano), 1 Missing)
1 CV Taiho (Included)
4 CL Agano (Included) - 1 was dropped from plan
2 CL Oyodo (1 Missing)
4 DD Kagero (Included)
13 DD Yugumo (2 Missing)
1 DD Shimakaze (Included)
6 DD Akizuki (Included)

1 CL Katori (Included)
4 AV Akitsushima (1 Included) - 3 were dropped from plan

Subs and Auxilaries

5th Program - 1941/1942
1 BB Yamato (Missing)
2 BB Super Yamato (Missing)
2 BC B65 Class (Missing)
2 CV Unryu (Included)
5 CL Agano (Missing)
4 CLAA Type 815 (Missing)
16 DD Redesigned Yugumo - AA refit?
16 DD Akizuki

Subs and Auxilaries

Amended 5th Program - 1942 (Post Midway)
Removed 1 BB Yamato
Removed 2 BB Super Yamato
Removed 2 BC B65 Class
Added 4 CV Taiho (Missing)
Added 11 CV Unryu (Some Included)
Removed 3 CL Agano
Removed 4 CLAA Type 815
Removed 8 DD Redesigned Yugumo - AA refit?
Added 7 DD Akizuki

Massive increase in subs and auxilaries

There are also further additions to the 5th program, but most of those arent on the wiki. One of them adds more subs.


As for the Ibukis. They arent in any of the major programs, apart from the 'cancelled two 13,000t CA' in the 4th one.

What I believe happened was they were slated to be included in that as two Tone-like CA, but were pulled (with a clause to reintroduce upon review) and then redesigned along the lines of Suzuya, and then added in some sub-program in 1941.

Thats just speculation though.

[mikemike]

ORIGINAL: Elouda


As for the Ibukis. They arent in any of the major programs, apart from the 'cancelled two 13,000t CA' in the 4th one.

What I believe happened was they were slated to be included in that as two Tone-like CA, but were pulled (with a clause to reintroduce upon review) and then redesigned along the lines of Suzuya, and then added in some sub-program in 1941.

Thats just speculation though.

I've looked into my Whitley, and he says that two repeat Tone CA's were authorized under the 1941 program, but in the view of experience redesigned as improved repeat Suzuyas.

The 1942 program contained five Oyodo CL, and the 1942M program two.

Concerning the destroyers, I've found the following:

1941: 16 repeat Yugumos, of which eight were cancelled (348-355), the others are all in
10 repeat Akizukis, of which six were completed (360-365, all in), Mochizuki was laid down, but cancelled and scrapped, the others were never begun.

Program 1942:
16 improved Akizuki (Arashikaru group, No. 770-785)
16 Shimakaze (No. 733-748)
all cancelled
29 Matsu DE (No. 5481-5509) 18 finished (all in), 11 cancelled

Program 1942M:
eight Yugumo (No. 5041-5048)
22 Akizuki (Yamazuki group, No. 5061-5083)
all cancelled

13 Tachibana DE (No. 5510-5522) all completed, all in

Program 1943/44:
20 Tachibana DE (No. 4801-4820) Hatsuyumo finished, all others cancelled. The nine boats of this group that were launched or laid down are all present in stock.

80 further Tachibanas were planned for the 1944/45 program, but all cancelled

[Terminus]

Far as I know, the Type 815 was just more Katoris. Why on Earth waste more time on those?

[Elouda]

@Mike;

Thanks. A lot of those agree with what Ive got, but there seems to be some differences in the later DDs. Maybe some of these are from the other subsidiary circle 5 programs?

As for the Ibukis, like I said its just speculation, as I could find nothing more on these '13,000t CAs' mentioned in the circle 4 amendments. Was just trying to tie these into the Ibukis we know which were introduced in the 1941 program.

As for the 'Oyodos' you mention...the numbers seem right, but my sources state them as an 'improved agano class', with 2,000t more standard displacement, which makes them a tad heavier than the Oyodos. Weaponry is 4xIIx6in/50 and 4xIIx3in/65. Speed of 38kt.


@Terminus;

The displacments match the Katoris at 5,800t, but the weaponry is definately intended as AA with 4xIIx3.9in/65. Nothing mentioned about speed, maybe the loss of some of the guns actually meant they could travel at ~30kts. Its also noted they were to be equivalents to USNs Atlanta class. Who knows.

[Dili]

Tiornu--What is L&W?

I think he means this: http://www.amazon.com/Japanese-Cruisers ... 0870213113


Note that Maya got one of 8" turrets taken out for another pair of 5"(in reality 6x5"Turrets replacing 4x4.7") at end of 43-begin 44. I would not be suprised that new Suzuyas(serie II) would get that too.

[John 3rd]

This is all great stuff!
 
Dili--Thanks for the clarification.
 
I wonder if we could recreate the additional building into something coherant that could be added into the build list for many choices and a lot of fun for the JFB out there? 
 
I know Nemo designed some Japanese AA cruisers in his Empire Ablaze Mod.  Maybe they could serve as a model to add here?
 
Nemo---You out there???

[Terminus]

ORIGINAL: Elouda

@Mike;

Thanks. A lot of those agree with what Ive got, but there seems to be some differences in the later DDs. Maybe some of these are from the other subsidiary circle 5 programs?

As for the Ibukis, like I said its just speculation, as I could find nothing more on these '13,000t CAs' mentioned in the circle 4 amendments. Was just trying to tie these into the Ibukis we know which were introduced in the 1941 program.

As for the 'Oyodos' you mention...the numbers seem right, but my sources state them as an 'improved agano class', with 2,000t more standard displacement, which makes them a tad heavier than the Oyodos. Weaponry is 4xIIx6in/50 and 4xIIx3in/65. Speed of 38kt.


@Terminus;

The displacments match the Katoris at 5,800t, but the weaponry is definately intended as AA with 4xIIx3.9in/65. Nothing mentioned about speed, maybe the loss of some of the guns actually meant they could travel at ~30kts. Its also noted they were to be equivalents to USNs Atlanta class. Who knows.

That sort of speed increase would have required a big, big investment in machinery and boilers, and the Katori design wasn't up to it. And eight 10cm guns are not equivalent to 12 5in guns.

[Terminus]

As for CLAA's, in my mod I've refit all the old IJN CL's to CLAA's with the 12cm guns. More realistic, since the Japs were incapable/unwilling to produce the 10cm guns in large numbers.

[Elouda]

Thats why I dont think they were based on the Katoris, but on a new design alltogeather. Getting ~30 kts out of a 6,000t cruiser isnt exactly difficult as far as naval designs go, and that would be enough to make a decent AA escort. I have no idea why the armanament on it is so light, its basically equivalent to an Akizuki DD. Search '815号型軽巡洋艦', and thats what you get. If anyones seen any other references to a dedicated class of CLAA, would be nice to know.

As for the 3.9in/65, its questionable if they were incapable/unwilling, or if they instead decided not to since most of the designs (More Oyodos, Taihos, Shinano and later Yamatos) that were intended to use it were clearly not going to be finished. We know they produced them in some reasonable quantity for the Akizukis, so its not impossible.

Last point about the refit of Mayas No.3 gun for more AA - I could see this being done to other Takao or maybe Nachi class CAs, as the firing arcs for the No.3 gun were pretty bad. However, if the Ibukis were to be based off the Mogami/Suzuya design, Id argue that this most likely would not have been done as the firings arcs were much less restricted on these designs.


Edit; Heres a nice listing of all of the programs, including the ones that werent on the wiki - http://forum.axishistory.com/viewtopic.php?t=91750

Another intresting tidbit on upgraded Shimakaze class, and the improved Agano class I mentioned - http://en.wikipedia.org/wiki/Super_Shim ... _destroyer

[Terminus]

Well, several written sources lump the 815s in with the Katoris, so they were probably batch 2 of that class. Not a good basis for further development, building a larger number of Akizukis would have been better.

That's the reasoning behind my CLAA conversions in my personal mod. Feed the limited number of 10cm gun mounts into the Akizukis, and give the older CLs the more common 12cm guns. The Japs are on a severe shipbuilding budget.

[Elouda]

Thats fair enough, but its hard to believe they would consider basing them on the same design when they even cancelled the 4th Katori once war started. Maybe they were an improved hull, and the reason for the incredibly light weaponry is precisely that all that weight was needed for machinery.

I cant find out much about them at all. It could be they were only intended to make 25kts or so, enough to keep pace with the older BBs? Just speculating...its not like we need a CLAA with weaponry like that, Id much rather build more Akizukis.

[Terminus]

A 25-knot speed for a CLAA is as useless as an 18-knot speed.

[Lameduck]

For what it's worth, the second Ibuki (Job No. 301) was laid down on 1 June 1942 with the work suspended in July 1942. It looks like it would have had ten 8" guns.

It looks like that there were another six of the Oyodo's (Nos. 810-810 and Nos. 5037-5038) projected under the 1942 program, but they were never actually ordered. Niyodo was canceled before it was laid down.

Another Katori, the Kashiwara, was laid down 23 June 1941 but work was stopped on 6 November 1941. Another three were projected under the 1942 program, but never started.

I don't see anything about more Agano's planned.

This is from Warships of the Imperial Navy, 1869-1945.

[Elouda]

Numbers 810-814 and 5037-5038 are labelled as the redesigned 'Kai-Agano', according to a variety of sources, notably Nihon junyokan monogatari (Fukui Shizuo chosakushu) - Collection of writings by Sizuo Fukui Vol.4, Stories of Japanese Cruisers.

Also, it was originally 5, but was reduced to 2 in the modified (post midway) 1942 program.

However, its entirely possibly that theres some confusion as to this as theyre larger than the original Aganos and more comparable to the Oyodos in terms of size.

[John 3rd]

How would those CLs have differed from the Agano-Class?  I've always felt that those CLs were really nice ships and pretty well balanced with speed, 6" guns, and Long Lances.  They didn't compare with the American Brooklyn's but...
 
If they displaced more then what was there planned armament?