The PERFECT WAR Mod

[FatR]

ORIGINAL: Terminus
The above is a quote from a little paper I wrote for my own amusement on the issue of submarine warfare in our game. The point is turning the brains of the IJN away from seeing the submarine as a fleet weapon. On the materiél side, it has the IJN turning away from the giant fleet boats in 1935 and building medium-sized boats instead for use from forward bases. The subs also shift from the control of the numbered fleets to a single HQ.

A good idea. It will require expanded submarine tender costruction, but as subs, at least in terms of money, ate a massive portion of the fleet's budget in the last years before the war, that should be possible with proper planning.

[Terminus]

There would be no conversions of the original subtenders, for one.

[FatR]

ORIGINAL: Terminus

I think an Escort Command HQ should be created before war breaks out and spend a few years training alongside the submariners.

This is also very important, as IRL lack of attention to ASW training and tactics before the war was a major problem for IJN (USN had British to share their accumulated experience in this area). Similarly, submarine forces didn't honestly test their doctrine and tactics before the war.

[FatR]

ORIGINAL: John 3rd
I meant this to mean the Japanese would prepare to fight AGAINST a commerce war.

I thought about 18 Es laid down before the war and over 50 old destroyers refitted with escort function in mind.

A question to the devs here: does surface combat code treat DD/E/PC differently or it all just depends on ship's stats? I'd like to give above-mentioned refits a different class designation from the first-line DDs.

[Terminus]

No difference. Plenty of DD's upgrade to E's in the stock scens.

[Terminus]

Speaking of IJN convoy escorts, a pre-war escort command should lead to the consideration of a standard class of escort ship.

In my mod, I call it the Sakikata ("Companion") class. This is essentially an IJN Flower-class corvette, meant for ease of construction above all else. About 1,000 tons, 16 knots, 4,000-mile range, 1*10cm gun and 1*2pdr gun with 2 DC rails and 18 DCs. Space for an additional Y-Gun and up-arming to about 50 DC's upon start of the war.

[FatR]

ORIGINAL: Terminus

Speaking of IJN convoy escorts, a pre-war escort command should lead to the consideration of a standard class of escort ship.

In my mod, I call it the Sakikata ("Companion") class. This is essentially an IJN Flower-class corvette, meant for ease of construction above all else. About 1,000 tons, 16 knots, 4,000-mile range, 1*10cm gun and 1*2pdr gun with 2 DC rails and 18 DCs. Space for an additional Y-Gun and up-arming to about 50 DC's upon start of the war.

Rather too big, short-legged and underarmed compared to any of RL Japanese escorts. The idea of changes in the escort construction program, though, is sensible and logical, if the Escort Command exists before the war and tries to get its own slice of the budget pie. IRL, Shimushu-class escorts were not actually meant for escort duty, but for keeping tabs on the Soviets across the naval borders and economic zones in the north. They had rather complicated construction, simplyfing which took time on the following models. If there is a branch of the navy, clamoring for a mass-produced dedicated convoy escort, it might instead be developed separately before the war, with small test series already built.

[oldman45]

ORIGINAL: FatR

ORIGINAL: Terminus

Speaking of IJN convoy escorts, a pre-war escort command should lead to the consideration of a standard class of escort ship.

In my mod, I call it the Sakikata ("Companion") class. This is essentially an IJN Flower-class corvette, meant for ease of construction above all else. About 1,000 tons, 16 knots, 4,000-mile range, 1*10cm gun and 1*2pdr gun with 2 DC rails and 18 DCs. Space for an additional Y-Gun and up-arming to about 50 DC's upon start of the war.

Rather too big, short-legged and underarmed compared to any of RL Japanese escorts. The idea of changes in the escort construction program, though, is sensible and logical, if the Escort Command exists before the war and tries to get its own slice of the budget pie. IRL, Shimushu-class escorts were not actually meant for escort duty, but for keeping tabs on the Soviets across the naval borders and economic zones in the north. They had rather complicated construction, simplyfing which took time on the following models. If there is a branch of the navy, clamoring for a mass-produced dedicated convoy escort, it might instead be developed separately before the war, with small test series already built.

Might not be a bad idea to drop the Shimushu for a "Flower" type escort. They could also be built in regular ship yards which is a plus.

[FatR]

ORIGINAL: JWE

I would be very judicious about any technology transfers from Germany. Germany wouldn't do it in the first instance, and the Japanese doctrine was so vastly different that technology transfer would be non compos mentos. What you want to avoid is IJA SS Panzer Armies scouring the map. There wasn't much beyond electronics that Germany could offer, anyway. And even electronics she held close to the chest.

So, Metox, cool. Japan had a cavity magnetron way before Germany (or anybody else, for that matter), so what's the point in German radar technology? Perhaps German operational use would open some eyes, but not German radar technology in 1941. So forget tech transfer of uber, ober Nazi radar; it wasn't.

Aircraft engine technology was about the same, and I dare say Japan's was better, for radials. Germany perhaps had better fairing tech and aerodynamic modelling, but engines ? No! Airframes? No! Japan just didn't have the facilities to crack enough of the really high octane additives to make things go faster. So forget tech transfer of uber, ober Nazi airplanes; they weren't.

As to subs, everybody knew that wall thickness equated to diving depth. And everybody know about the moduli of T and S grade steel. Japanese ship designers weren't stupid. Japan had a bunch of german War-I boats to evaluate and decided .. nah .. not what we want for our purposes. So forget tech transfer of uber, ober Nazi sub tech; it wasn't.

Could go on and on, but this uber, ober, Nazi technology, wasn't. So please, oh please, don't go there.

I agree with this sentiment in general, but I do believe that Japanese would have benefitted from buying a license for an existing type of a flak cannon in 75-90mm range, or contracting one of European manufacturers to develop such cannon for them before the war (as they did with 25/60), instead of reverse-engineering guns they have captured from Chinese and British. Unfortunately, all high-ballistics, fully automatic 37-40mm guns potentially on the market before 1939 are poorly suited for mass production and/or naval use, so Japanese have nothing to obtain here.

[Terminus]

A case could be made that the IRL Jap escorts were overarmed, but that's neither here nor there. The IJN escort command needs hulls in the water, ships that can be built quickly and cheaply in yards that would otherwise be lying idle.

Secondly, the Sakikata is indeed relatively short-ranged, but the Jap convoy routes to the SRA are littered with ports that can be used as bases for escort groups, and my scheme envisions a sort of "relay race" where one group hands off a set of merchies to another on the way to the home islands.

Third, I wasn't clear enough about the "standard" escort: the IJN is to have three groups of early-war ASW ships:

- Old destroyers and torpedo boats with extra DC's.

- The Sakikata class.

- Small picket boat type classes, for doing point-defence ASW around ports.

Fourth, the whole idea of the Sakikatas is to give the IJN an EARLY-WAR escort ship, something to hold the line. Later in the timeline, you can build something similar to IRL escorts. It's not terribly realistic to start out with an escort type carrying 100+ DCs (nobody had that), but you can certainly justify it from 1943 onward.

[JWE]

ORIGINAL: Terminus
Fourth, the whole idea of the Sakikatas is to give the IJN an EARLY-WAR escort ship, something to hold the line. Later in the timeline, you can build something similar to IRL escorts. It's not terribly realistic to start out with an escort type carrying 100+ DCs (nobody had that), but you can certainly justify it from 1943 onward.

I do agree completely. Both the US and UK had extensive ASW experience in War-I and neither of them had dedicated escorts with big DC load-outs at the beginning of War-II. 24 to 36 was the best they had, from two stern rails. Brits added a Y-gun or 2, to those ships that had the open transom space (not bloody many), and the US followed (that was how they got from 24 to 36). It wasn't for quite a while till escorts got K-guns and a decent DC load-out. There's no reason that Japan, given its lesser involvement and experience, would be more perceptive (that's hindsight).

Japan should start with the ASW suites she had. But ... Japan had Shimushus and Hashidates (a few of each) on opening day, so rather than beefing up the ASW suite (not goodnik) just build some more Kaibokan. I like Termy's Sakikatas, but whether it's them or Shimushus, I think numbers are a better objective than early war capability. The cost issue is an apples to oranges thing. Ok, a Shimushu Type-A (or Etorofu/Mikura/Ukuru Type-B) was way more expensive than a Type-C or D, but compared to a 'special type' DD, they were butt-cheap; and way more cost effective for their mission.

I would go with Termy on this one.

[FatR]

ORIGINAL: Terminus

A case could be made that the IRL Jap escorts were overarmed, but that's neither here nor there. The IJN escort command needs hulls in the water, ships that can be built quickly and cheaply in yards that would otherwise be lying idle.

Secondly, the Sakikata is indeed relatively short-ranged, but the Jap convoy routes to the SRA are littered with ports that can be used as bases for escort groups, and my scheme envisions a sort of "relay race" where one group hands off a set of merchies to another on the way to the home islands.

Third, I wasn't clear enough about the "standard" escort: the IJN is to have three groups of early-war ASW ships:

- Old destroyers and torpedo boats with extra DC's.

- The Sakikata class.

- Small picket boat type classes, for doing point-defence ASW around ports.

Fourth, the whole idea of the Sakikatas is to give the IJN an EARLY-WAR escort ship, something to hold the line. Later in the timeline, you can build something similar to IRL escorts. It's not terribly realistic to start out with an escort type carrying 100+ DCs (nobody had that), but you can certainly justify it from 1943 onward.

Sounds solid this way, thanks for sharing your thoughts. The composition of dedicated ASW forces I had in my head is quite similar:
1)DD/TB conversions. Only the less valuable half, modernized TBs, will be actually given to the Escort Command. The Escort Command will want more, preferably newly-built DD-ASW (variations on Matsu theme), but these will remain only on blueprints before the war. Assigned for most vital convoys, whenever possible.
2)Kaibokans. Evolved from large subchasers, instead of Shimushus (note that type C/D escorts had the engines comparable to that of large Japanese SCs - 1700 hps on the most numerous Type 28 SC, 1900 on Type C kaibokan, so this is not a stretch). Still thinking on exact types. Large SCs are eventually abandoned by the Escort Command, due to their inherent inferiority. Kaibokans are workhorces of the Escort Command, doing most of the routine jobs.
3)Auxilary subschasers of sufficiently simple construction to be handled by small shipyards that were building fishing trawlers and other small coastal ships before the war. For escorting coastal convoys and harbor defense.

designed with the possibility of construction on civilian shipyards in mind. I don't think that production of a really stripped-down design is plausible before the war even then.

will want newer ships of similar capabilities (although it will not get them before the war), resulting in earlier development Naval Ministry

[John 3rd]

Been gone all day at the Denver Zoo. Nice give-and-take of ideas and concepts. Have no objection whatsoever to the ASW composition and command set-up.

Odd question: WHERE would be the appropriate place for a Japanese 'Coastal Command' HQ? Would it be in Osaka? Nagasaki? Tokyo?

[Terminus]

Kobe, right down the road from the submarine school. Helps to inculcate proper cooperation between the branches.

[John 3rd]

ORIGINAL: Terminus

Kobe, right down the road from the submarine school. Helps to inculcate proper cooperation between the branches.

PERFECT! I like the symmetry of that.

[oldman45]

FatR- they may not quit building the large SC's because they can be built at any yard and they are cheap and easy to build. Look at the Brits, the Flowers were not the best ASW platform but any yard could build them, in the mean time they are designing the newer boats that come out in 43-45 Rivers etc

[FatR]

ORIGINAL: oldman45

FatR- they may not quit building the large SC's because they can be built at any yard and they are cheap and easy to build.

That's the qualities that are neeeded from Es, except larger Es are considerably more operationally useful in all ways, while, as noted above, using only slightly more powerful engines, even compared to Ch-13/Ch-28 subchasers.

[FatR]

So, returning to our post-treaty battleships:

1)A 460mm gun is rejected during early research stages because of its massive cost of its production and replacing guns that exceeded their barrel life (relining them was practically impossible). As the conflict is expected to be protracted, this is unacceptable. A more modest 410/50 gun is created for new battleships instead.
2)This leads to increased emphasis on maintaining a favorable distance of engagement in a battleship battle. In combination with greater influence of the carrier faction, leads to requirement of 30-knot speed.
3)Protection remains on the level of Yamato, to ensure qualitative superiority against American and British battleships. Greater accuracy of Japanese heavy guns at long ranges alone cannot ensure this superiority in a battleship battle, and increasing the number of guns beyond 9-10 will make the ship even more heavy, making it difficult to achieve the necessary speed.
4)All possible weight-saving measures are implemented to achieve necessary speed. Secondary anti-DD battery is not used. Instead it is planned to arm the new BBs with about 20 of 120/55 DP guns, still in development during its design, but delays with their development and production will cause the first two new battleships (those available before the war) will be initially armed with old 120/45 Type 89 twins. All main calibre turrets are positioned forward, to reduce the citadel's length, like on the initial A-140 project:

Reduction in range to about 6000-7000 nms can be accepted, if necessary. 8000 is the desirable figure.

The questions are - can the most powerful Japanese turbine (160 000 hps) produce the necessary speed on this project (so that we won't inadverently go past both plausibility Yamato's price tag), and what will be its displacement?

[Terminus]

Are you replacing or supplementing older classes, because I could see this as a Kongo replacement class.

46-48,000 tons and 29 knots.

[FatR]

ORIGINAL: Terminus

Are you replacing or supplementing older classes, because I could see this as a Kongo replacement class.

I suppose project A-150 will be meant to serve as Nagato replacement then[:)]. But indeed, without the war these ships might well eventually replace Kongos, when the latter will be too worn out for use, but the war will happen before that. As all Kongos but Hiei finish their second reconstruction 3-4 years before these ships will be available, said reconstruction still happens as IRL.

ORIGINAL: Terminus
46-48,000 tons and 29 knots.

29 is acceptable, I think.