A New Set of BTS, RA, and Treaty Mods

[John 3rd]

The old Reluctant Admiral web site has been shut down due to age. I have commissioned my 17 Year-Old Christopher to develop me a new web page that I can fill with all the RA information. He thinks that he can get it going by the end of this weekend. Sorry about the issues for anyone trying to gain assess to the Mods!

Had a long conversation with Michael while we were driving back-and-forth to Craig on Tues-Wed and have made some major Mod decisions. We are going to create three variants of Between the Storms: Traditional/Fleet Faction, Moderate, and All-In/Fleet Faction. The thinking is what would have happened if Yamamoto couldn't drive out the 'Fleet' Faction (Traditional with Yamato's), partially wins and brings in more 'Treaty' Faction leadership (Moderate with several conventional 16" gun BBs and B-65 Battlecruisers), and then totally drives out the 'Fleet' Faction and the 'Treaty' Faction completely takes over the Kaigun (little-to-no heavy ship construction with complete CV emphasis).

It has been a long, LONG time since I had some motivation to go back into serious Modding. Looks like that is about to occur!

The Site will feature five Mods available for play. They will have the three BTS Variants (covering 1922- 1941), the original Reluctant Admiral (1937-1941), and then the Treaty Mod (1922-1936).

BANZAI!

[John 3rd]

This Thread will cover the separation of the Mods, changes included within them, and when they are available for play and download.

There will be BUNCHES of chances for you to jump in and toss out your opinions. Looking forward to getting this GOING!

[John 3rd]

Between the Storms (12/20/17)
ALTNAV 1922-1937

The Treaty Mod for AE has been created to reflect a slightly different outcome of the historic Washington and London Naval Conferences to cover the time of 1922-1937. With little changes and tweaks to the Treaty System, a slightly a-historic outcome is produced. The Treaty Years give way to the ramping up of World War Two. Japan grapples with the consequences of exiting the Treaty System and works to create a more balanced Fleet under the able leadership and foresight of Naval Minister Yamamoto Isoroku.


The Washington Conference
Secretary of State Charles Evans Hughes blueprint for naval disarmament gets out and the Japanese stonewall a Naval Conference for a full year. After considerable bickering and pressure being brought to bear, the Conference does take place in 1922 and disarmament is agreed upon, however, there are additions allowed due to the added time to get the meeting going. The whole Mutsu debate is scrapped due to Mutsu actually being ready and deployed at that point. A slightly higher 10:10:7 ratio between Great Britain, the United States, and Japan is agreed upon, allowing for several new outcomes:

1. The Ratio Change to 10:10:7:
a. The Japanese argue to keep the nearly complete battleship Tosa and the Amagi-Class battlecruiser Ishitaka. The Americans gain the fourth Colorado-Class USS Washington and the Battlecruiser USS Constellation (while scrapping the old battleships Florida and Utah and making the Wyoming into a gunnery training ship to maintain balance), Great Britain gets the option to build a pair of Super-Hoods.
b. Tonnages are left open for the British to build two 35,000 Ton battleships (Rodney and Nelson), the United States has 28,000 Ton available, and the Japanese have 18,000 Ton open for new Capital Ships. These warships are designed through the late-20s and are authorized for building at the time of the London Naval Conference. The United States builds a fast Battlecruiser (USS Chesapeake) armed with 4x3 12" Guns while the Japanese build a Light Battlecruiser named Chichibu (2x2 16.1" Guns).

2. The whole subject of CVs is reworked:
a. Two 'experimental' CVs (two Hosho's and two Langley's) are allowed to be built for further carrier experimentation. The Americans convert USS Langley and USS Ely to CVEs and they begin the war at the Panama Canal. Japan has IJN Hosho and Ibuki.
b. Two BC to CV conversions are still allowed. The Americans use all their Treaty tonnage to make Wasp a 4th Yorktown-Class CV. The Japanese back off the failed Ryujo design to build IJN Ryukaku and Karasu while Soryu enters as a Hiryu-Class CV.

3. The Big 3 allow for more research into 'Cruiser' Submarines. Since no one had any real idea of where submarines were headed, this allows for further experimentation. The Americans build an additional Argonaut, Narwhal, and three Seaplane carrying subs. The Japanese add three Mine Layers and four large ocean-going Glen SS, and the French add another Surcouf.

The London Conference
Moving on to the London Conference (1930), the subject of Cruisers is re-worked:
1. Japan--at all costs--sticks to its goal of 70% for CAs (instead of 60%). Japan wins and is authorized to build a total of 14 CAs while the US and GB keep their 18.

2. Great Britain--who nearly scrapped the treaty due to the issue of CAs and CLs--stands firm over its argument and forces a larger tonnage for CLs. This brings no change to the Treaty since Japan was already at 70% in this category.

3. Both Japan and the United States were looking at hybrid Cruiser—CVs and they force Great Britain, following the example set with the Washington BC—CV Conversions, to allow for two hybrids each to be built in the early-30s. The nations are allowed with ONLY these two vessels to place up to 8" guns on them. USA builds CLV Charlotte and Jacksonville (3x3 6" and 18 Planes), GB builds CAV Melbourne and Wellington (sold/given to those respective navies with 2x2 8" and 15 Planes), and Japan finishes up with CAV Kushiro and Tokachi (3x2 8" and 27 Planes). These hybrids are not true, useful CVLs nor are they true, useful cruisers but they have a unique niche in 1941 and ALL of them can be converted into carriers later in 1942.

American Admiral’s Moffat and Reeves argue—and win—for the allowance of up to 25% of cruiser construction to be of the Flightdeck Cruiser variety. While a historically accurate argument; however, THIS reality allows for a further pair of Flightdeck Cruisers to be built. Japan begins with two, NZ one, Aust one, and the USN has FOUR.

***It should be noted that to take maximum advantage of the revised Treaty tonnages, Japan converts several of the oldest CLs into fast ML, builds additional Myoko-Class CAs and keeps the last four Mogami-Class as 6” CLs.


Warship Construction AFTER the Treaty Years
Battleship Question and Decision
Staying historical the Japanese decide to build the super-battleships of the Yamato-Class. All four are represented in this Mod. Shinano and Aki are built as BBs and they will use BUCKETS of shipyard points but they are Japan's for the asking.

Command Cruisers
In the 3rd Circle Plan a new class of heavy cruiser is initiated. The proposed Tone-Class floatplane CA is discarded for a balanced, more capable cruiser. These large cruisers are better called command cruisers. The Niitaka-Class grows to over 15,000 tons and carries 4x3 8" guns, heavy torpedo armament, impressive secondaries, and strong floatplane complements. These fast, rugged cruisers are planned to be a six-ship class. The initial two are complete at war's start, a second pair coming in late-1942, and a final pair in 1944.


The Rise of Admiral Yamamoto

As the Treaty Period ends, history takes another turn as Admiral Yamamoto Isoroku makes a greater contribution to the development of the Kaigun from 1936-1941. Yamamoto exerts a much greater influence first on the Japan Naval Aircraft Industry, then as Deputy Navy Minister, and finally as Navy Minister itself. Yamamoto chooses, at great risk to his life, to forego command of the Combined Fleet and dedicate himself to preparing Japan for the war he didn't want. He adds two new slipways (Shanghai and Port Arthur) for Fleet construction to facilitate a different, final pre-war expansion of the Kaigun. New and expanded Naval Yards, Heavy Industry, and Armaments are added at tremendous cost for the Japanese economy as the Admiral attempts to prepare Japan for a possibly long war. In so choosing to do this Yamamoto then changes the 4th Circle Building Plan stopping the 3rd and 4th Yamato-Class Battleships (in BTS-Heavy), adding two improved Shokaku-Class CVs, a pair of Kawachi-Class fast Battlecruisers, an accelerated Light Cruiser deployment, and additional destroyers. Quick, reasonably cheap carrier conversions are moved forward seeing all of the pre-war CVs/CVLs deploy by December 7th or at slightly earlier dates in 1942. The highly unrealistic 5th Circle Plan is added in late-1941 and adds the 3rd and 4th Yamato-Class BB back into building que. Despite Yamamoto's arguments this allocation of resources goes ahead with completion dates set in 1943-1944. Though only a few of these new ships are ready on December 7th, these additions make the Kaigun a force to be reckoned with well into 1944.

The Japan Naval Air Arm deploys its magnificent A6M2 with research complete for its land-based successor the M3. These airframes are ready in December 1941 and the Japanese wisely look at advanced prototypes elsewhere and decide to explore several second-generation fighter concepts. The Zero Team moves on to the A7M1 Sam (no Jack), while private contractors work on the George. Yamamoto fosters a sense of competition between the two teams to see who will win out as having a worthy successor to the A6M2 line. Additional streamlining and encouragement brings forward second-generation aircraft of other fields--Dive-Bombing, Torpedo-Bombing, and the creation of a small heavy bomber line.

On the ground Yamamoto reorganizes the SNLF units into a Brigade-Sized offensive force and—knowing it will be a war of attrition—converts many Naval Guard into enhanced units with Coastal Defense artillery (using guns taken from refitted warships) for a stronger defensive unit. Additional small units are added to the IJN’s Troops and support units better reflecting Yamamoto's foresight into base building, defense, and expansion needs. While all these units are small and not in great number they promise to help the Japanese war effort.

The foresight of the Admiral pays off during late-1942 and 1943 as new ships, aircraft, and ground units enter into the Japanese Order-of-Battle, however, the cost is steep. Though expanded and using modern aircraft many Japanese Naval Air units start with their experience lowered to reflect the dilution of the experienced pilots into new units that start in Japan or arrive during 1942-1943.

Supply and fuel reserves start at a much reduced state. The Japanese MUST take the DEI as fast as possible!
Once war begins BTSL postulates Yamamoto’s influence upon the wartime Kaigun. Four more improved Shokaku-Class CVs are ordered, and the conversion of several CLs into CVLs is added. First class destroyers continue to be accelerated and emphasis is shifted to the AA Akizuki-Class at the expense of the more balanced Yugumo’s. Manpower is at a premium within the Fleet so Submarines, Escorts, and ASW forces all see a major retooling reflecting the Japanese quality over quantity belief. Yamamoto chooses the immediately useful projects, large APs converting to CVEs, better destroyers, fast transports and coastal defense forces.


Allied Response
It should be noted that not all the changes are for the Japanese. Between the Storms brings major additions and more choice for the Allied Player. The Allies see continued major changes in their starting locations, new air units, the addition of Training Squadrons on mainland USA to allow for an American pilot training program, enhanced aircraft production numbers, additional Allied FP groups, several ground units, additional New Zealand and Australian ships, a French Squadron at Tahiti, the Dutch actually complete their planned naval force of 5 CL and 12 DD for the DEI, a stronger Force Z, a CLAA conversion for the Omaha-CL, an additional pair of CVLs, and optional conversion of the Kittyhawk Class AKV and Tangier Class AV into CVEs. The added warships reflect a ‘stopgap’ counter to the increased Japanese strength found at war’s start.

Additionally, the Hepburn Board's recommendation to augmenting and expanding many Pacific Bases in 1938 is heeded and work is sped up at Wake, Midway, the Aleutians, and in the South Pacific. While work has just begun in many ways, these advances pose a tougher problem for Japan if she moves east or southeast.

Following the Destroyer-for-Bases deal in September 1940, President Franklin Roosevelt offers the Dutch government in the East Indies if they could use the old BB’s Texas and New York. The offer underscores the seriousness of the Japanese build-up. It is meant as a deterrent and the Dutch gladly agree. Freshly renamed Prins Hendrik and Prins Willem, these BB join several other new Dutch ships to constitute a real threat to the coming Japanese attack.

As war clouds gather on the horizon, the United States makes several important decisions (1) to slightly reinforce the Asiatic Fleet with an additional CA and 4 modern DDs, (2) Admiral Hart also decides to follow his inner thoughts and begin development of Cebu as an alternate anchorage, and (3) speed up the reinforcement of the islands. The Pensacola TF is reinforced by the CLV Charlotte and arrives at Manila December 1, 1941. The TF unloads its squadron of P-40s and 3 squadrons of A-24 dive-bombers, several artillery batteries and a base force. The convoy then departs and moves south to unload another artillery unit and base force at Del Monte Field near Cagayan. This is where war finds it.
In the Central Pacific, the Pacific Fleet Scouting Force, commanded by Vc-Adm Wilson, is sent south to protect the ships helping to develop Pago Pago into a forward operating base. This powerful set of Task Forces serves to aid the convoys and the empty TF returning from the Philippines (The CLV Anacostia TF). CV Enterprise and Lexington plus the battlecruiser TF commanded by Wilson are NE of Pago Pago. Additionally, CVL King’s Mountain and her TF are returning from delivering a Marine F4F squadron to Wake Island.

In a major development Winston Churchill decides, at the last minute, to add HMS Renown to Force Z to better demonstrate British 'resolve' reflecting the seriousness of Japan's overt aggression. Repairs on HMS Indomitable are rushed and this valuable carrier and her escorts are just days away from assisting Force Z by providing invaluable air cover. A Gurkha Brigade is rushed into Singapore along with supplies and two dozen crated Hurricane Fighters. Is it too little, too late?

How well can YOU do to use these new tools OR how well can you stop the Japanese Navy in its tracks as the Allies?
Scenario Notes

In addition to its own special modifications, Between the Storms has been made fully compatible with DaBabes and thus has more ship classes than stock, and many more of the smaller vessels comprising these classes for both sides: yard oilers, coastal minesweepers, auxiliary subchasers, patrol boats, minefield tenders, and many others designed to give a more robust and realistic feel to the development, population, capabilities, and logistical support of bases and rear and operational areas. Database elements have been modified to provide more realistic results for AAA (flak) combat, ASW combat, and certain minor, but nevertheless fun, aspects of naval combat, like land bombardment and coastal defense fire and new modifications to ATA combat. The modifications include lining-up and unifying data elements within certain fields, so that things interface more smoothly, as well as substantial changes to the data elements themselves.

Garrison requirements have been raised in China as well as India to, hopefully, better reflect the political environment of the regions.

If using the special road movement pwhexe.dat file this serves to slow movement in the CBI Theatre.

[John 3rd]

There is TONS of Naval History here. The mentions of Yamamoto, Adm. Reeves and the Hybrid Cruisers, the Hepburn Board, the Pensacola TF, Churchill's decisions and choices with Force Z are all real topics. My library carries BUNCHES of books covering these questions. Am always willing to SHARE where these choices and discussions happened IRL.

[btd64]

Looks interesting John....GP

[RangerJoe]

A question for you. Since the Japanese did have a few 40mm AA guns and probably captured some early in the war that they could copy, would you consider having some of the 25mm AA guns swapped with 40mm guns on a 3:2 basis on some ships? Also not using the 127mm AA rockets but using 40mm AA guns instead?

[John 3rd]

Hey Guys.

I have some 40MM upgrades in the mid-44 and later modifications. Those upgrades focus on the capital ships: CV, CVL, BB, and BC see a few of the 40MM added. They are not in great quantity but reflect some hard-learned lessons.

[John 3rd]

Have some time at home to do a few broad strokes:

BTS--Fleet Faction
This Mod would replace BTS Heavy. The Japanese build 4 Yamatos (3x3 18.1") and the Fuji-Class LBC (2x2 14"). The Japanese get their allotment of 6 Shokaku-Kai CVs as well as the 3-4 CVLs during the war. The heavier ship emphasis could see more of the Mogami-Class (5x3 6") CLs as well as more Shimakaze-Class DDs (39 Knots and 3x5 Long Lance Mounts).

BTS--Moderate
Mod replaces BTS Lite. No Yamato-Class. The Japanese build 4 Owari-Class BB wih 3x3 16" Guns. There are an additional pair of B-65 BC. Same numbers of Japanese carriers. Build a few CAs and 'regular' CLs (3x3 6") as well as some Kagero/Moon-Class AA DDs/a few Shimakaze-Class...

BTS--Treaty/Air Faction
New Mod. Do we build...say...4 B-65 BC with NO BBs? Do we build NO BB or BC and, instead, replace them with Shokaku-Class CVs? If we go with no Capital Ships, how about the Japanese build Niitaka-Class Command Cruisers (4x3 8" coming in at about 15-17,000 tons) as well as more CLs (3x3 6")? There would be heavier production of Moon-Class DD and maybe NO Shimakaze-Class?

What do people think?

I have all the shipyard charts and graphs for, realistic building of heavy warships (CVs--BBs--BCs).

[JanSako]

Depends on how 'plausible' you want to go or how far off.
I do not see it plausible to go with 0 BB's. BB's was what won the previous wars & no major naval power would go all in on an untested concept like the CV. That is what CV's were in the 20's.
Going heavy on CV's and having more of them in the build Q once their power has been demonstrated (say after Pearl), yeah, by all means. Obviously the lead time needed to build matters too, of course.

Funny, I was going to bring up the example of tank not being a (mainstream) major factor in land war planning until it prove it's worth in Spain (a bit) and Poland, then I remembered that SOV went pretty much all in on tanks. That they were not considered a 'major player' pre-ww2 or that they did not really know what to do with all those thousands of tanks at the beginning is a different issue, of course!

I am just thinking that if the tank gamble did not work, the Soviets still had Infantry & especially artillery to fall back to. What would Japan have if an all-in on CV did not work?

Or, putting an alt-history hat on, what sort of event would be plausible that would demonstrate that the all-in CV is a valid doctrine change?

[John 3rd]

Between the Storms: Fleet Faction (Heavy)

Capital Ship and Carrier Production:
1. 4 Yamato-Class (Yamato 3/42, Musashi 7/42, Shinano 1/4, and Aki 11/44)
2. 4 Light Battlecruisers of the Fuji-Class (Aino 3/42, Okuhotaka 11/42, Yari 8/44, and Warusawa 1/45)
3. 6 CVs
---2 Shokaku-Class (Kaimon 8/42 and Taikaku 3/43)
---4 Shokaku KAI-Class (Renkaku 9/43, Taiho 7/44, Katsuragi 11/44, and Kasigi 1/45)
4. 4 CVL of the Aso-Class (Aso 11/42, Shinryu 4/43, Unryu 11/43, and Kurama 1/45)

Classes
Yamato--Same as IRL.
Fuji-Class--(2x2 14" and 2x3 6")
Shokaku KAI-Class--3,000T more, slightly more AA, and 81 Planes
Aso-Class--Converted from CL hull, 36 Planes, and 33 Knots

No CA being built in this Mod. The CB are basically really mean 17,000 panzershiffe!

While shipyards are expanded in BTS, the massive amount of BIG construction is TOO much for the starting shipyards. The MOd forces you to spend the $$$ to expand the yards OR make choices on what you are building. Love to force players to make choices...

[John 3rd]

Between the Storms--Moderate (Lite)

Capital Ship and Carrier Production:
1. 2 Owari-Class (Iwaki 6/43 and Aki 11/44)
2. 1 B-65-Class BC (Kasuga 6/43)
3. 6 CVs
---2 Shokaku-Class (Kaimon 8/42 and Taikaku 3/43)
---3 Shokaku KAI-Class (Renkaku 9/43, Taiho 7/44, Katsuragi 11/44, and Kasigi 1/45)
4. 4 CVL of the Aso-Class (Aso 11/42, Shinryu 4/43, Unryu 11/43, and Kurama 1/45)
5. 4 Niitaka-Class CA (Abashiri 6/42, Yubetsu 11/42, Shizunai 3/44, and Zenbako 9/44)

Classes
Owari-Class BB--3x3 16", heavy 10CM secondary, strong armor, 30 Knots, and 45,000T
B-65 BC--3x3 14", heavy secondary, 33 Knots, BC armor, and 31,500T
Shokaku KAI-Class--3,000T more, slightly more AA, and 81 Planes
Aso-Class--Converted from CL hull, 36 Planes, and 33 Knots
Niitaka-Class CA--4x3 8", good secondary, strong Long Lance, 32 Knots, and 16,000T

An easier build that excels with 2 Owari-Class and 1 B-65 already in service on Dec 7th.

Still have to juggle the building some but not nearly impossible as the Fleet Variant.

[John 3rd]

What might BTS--Air/Treaty Faction look like? Not sure. All sorts of possibilities...

Think you must build some sort of Capital Ship. Could build some B-65 and Niitaka-Class for new escorts.

Thinking here could be radical and one replaces the Shokaku/Shokaku KAI with a bunch of Unryu-Class medium sized CVs. Instead of building 6 CV of 72-81 plane air groups, could you build 9 medium CVs with 63 planes each???

Hmmm...

Opinions???

[ny59giants]

BTS--Treaty/Air Faction
New Mod. Do we build...say...4 B-65 BC with NO BBs? Do we build NO BB or BC and, instead, replace them with Shokaku-Class CVs? If we go with no Capital Ships, how about the Japanese build Niitaka-Class Command Cruisers (4x3 8" coming in at about 15-17,000 tons) as well as more CLs (3x3 6")? There would be heavier production of Moon-Class DD and maybe NO Shimakaze-Class?

I had been watching a video on YouTube by Drachinifel (he has put out great video's on WW2 naval stuff over the years) of Yamamoto's life up to attack on Pearl and discussed various parts that I found interesting. In mid-30s, Yamamoto had voiced opposition to the Yamato Class BBs. John had done a Heavy and Lite mod and I brought up doing one where the Naval Air Admirals win out. Rather than heavy Industries being spent to expand the engraving docks to build the Yamato's, they lay down two more Shokaku Class CVs. Furthermore, any additional ships will need to have minimal speed of 32 knots. We keep the concept of 2 Heavy CV and 1 CVL per CarDiv.

John and my overarching goal is for Japan to be competitive for another year or more than most games go. This new mod may be another way to achieve this. I'm more aligned with this now than ever after reading "Hell to Pay" by D. M. Giangreco that covers Operation Downfall. I talked John into buying this book and he is now more than halfway through it. I was under informed on how costly the invasion of Japan would have been.

[ny59giants]

BTS--Treaty/Air Faction
New Mod. Do we build...say...4 B-65 BC with NO BBs? Do we build NO BB or BC and, instead, replace them with Shokaku-Class CVs? If we go with no Capital Ships, how about the Japanese build Niitaka-Class Command Cruisers (4x3 8" coming in at about 15-17,000 tons) as well as more CLs (3x3 6")? There would be heavier production of Moon-Class DD and maybe NO Shimakaze-Class?[/quoteI

I know we cannot get rid of complete hindsight, but IRL they were very few BB vs BB engagements. Japan and to a limited amount the US Navy focus on flattops and speed in their production of warships. Rather than the Japanese being able to out range the US Navy BBs by the Yamatos, they do so by speed (over 32 knots) CV/CVLs and BCs, longer range airframes (Zero, Jill, Judy), and TT (long lance) on their smaller warships.

[John 3rd]

Hah! That is my co-writer hard at work jumping into things.

One thing to know about both of us, our version of these AltHist timelines and 'what ifs' are always based on books we have read. Michael is correct about his 'Hell to Pay' comments. If you have not read this book about what Operations Coronet and Olympic, DO SO! Revisionists have done a lot of damage to the true probable costs of final assaults upon Japan vs use of the A-Bomb that this book really, REALLY opened my eyes.

[John 3rd]

The Japanese Capital Ship OOB going into all three of these possible Mods to 1936 is:

BatDiv1 Nagato, Mutsu, and Tosa
BatDiv2 Fuso, Yamashiro, Ise, and Hyuga
BatDiv3 Kirishima, Hiei, Kongo, Haruna
BatDiv4 Ishitaka and Chichibu

The additions of Tosa provides nice punch but Ishitaka is a magnificent addition as that Amagi-Class BC is FAST and packs 10 16" guns. The Chichibu is also a fast Light BC that uses up the last of Japan's Treaty tonnage allotment.

This is the starting Capital Ship allotment when Yamamoto comes in...

[1EyedJacks]

Depends on how 'plausible' you want to go or how far off.
I do not see it plausible to go with 0 BB's. BB's was what won the previous wars & no major naval power would go all in on an untested concept like the CV. That is what CV's were in the 20's.
Going heavy on CV's and having more of them in the build Q once their power has been demonstrated (say after Pearl), yeah, by all means. Obviously the lead time needed to build matters too, of course.

Funny, I was going to bring up the example of tank not being a (mainstream) major factor in land war planning until it prove it's worth in Spain (a bit) and Poland, then I remembered that SOV went pretty much all in on tanks. That they were not considered a 'major player' pre-ww2 or that they did not really know what to do with all those thousands of tanks at the beginning is a different issue, of course!

I am just thinking that if the tank gamble did not work, the Soviets still had Infantry & especially artillery to fall back to. What would Japan have if an all-in on CV did not work?

Or, putting an alt-history hat on, what sort of event would be plausible that would demonstrate that the all-in CV is a valid doctrine change?

Yamamoto was in the US for a bit - what would he have seen realistically? The Hosho was the first actual flat top - right? Yamamoto was in the US in the early 20s, did flight training in 1924 (Japan), and was back in the US from 26-28. America and the British Navy were filling out DB airframes. I'm not sure when the first Torpedo Plane came out - the TBD-1?

[RangerJoe]

Depends on how 'plausible' you want to go or how far off.
I do not see it plausible to go with 0 BB's. BB's was what won the previous wars & no major naval power would go all in on an untested concept like the CV. That is what CV's were in the 20's.
Going heavy on CV's and having more of them in the build Q once their power has been demonstrated (say after Pearl), yeah, by all means. Obviously the lead time needed to build matters too, of course.

Funny, I was going to bring up the example of tank not being a (mainstream) major factor in land war planning until it prove it's worth in Spain (a bit) and Poland, then I remembered that SOV went pretty much all in on tanks. That they were not considered a 'major player' pre-ww2 or that they did not really know what to do with all those thousands of tanks at the beginning is a different issue, of course!

I am just thinking that if the tank gamble did not work, the Soviets still had Infantry & especially artillery to fall back to. What would Japan have if an all-in on CV did not work?

Or, putting an alt-history hat on, what sort of event would be plausible that would demonstrate that the all-in CV is a valid doctrine change?

Yamamoto was in the US for a bit - what would he have seen realistically? The Hosho was the first actual flat top - right? Yamamoto was in the US in the early 20s, did flight training in 1924 (Japan), and was back in the US from 26-28. America and the British Navy were filling out DB airframes. I'm not sure when the first Torpedo Plane came out - the TBD-1?

Ummmmm . . .

Maybe the first torpedo plane came out before the First World War?

". . . The first successful aerial torpedo drop was unofficially performed by the later RFC pilot Charles Gordon Bell on 27 July 1914 - dropping a Whitehead torpedo from a Short S.64 seaplane. Gordon Bell was followed the next day by RNAS pilot Arthur Longmore, when officially testing an aerial torpedo. The success of these experiments led to the construction of the first purpose-built operational torpedo aircraft, the Short Type 184, built from 1915."

https://en.wikipedia.org/wiki/Aerial_torpedo

[John 3rd]

This is from the Old Website. The document shows the changes by year/Treaty/Plan as well as nation:

OOB Changes/Additions for Japanese and Allied Fleets

Additional/Changed Japanese Ships built:
Washington Treaty Years (1922-1930)
CV Amagi instead of CV Kaga
CVL Ryukaku
CVE Ibuki
BB Tosa
BC Ishitaka
LBC Chichibu
CA Yoshino, Miyako, Chishima, and Seiki (Myoko-Class)
CL Minase, Otonase, and Ayase
DD +4 Minekaze-Class
SS +3 ML SS and +4 I-Boats

The Treaty comes a year later than historical allowing for Mutsu to be completed without a fight as well as bringing Tosa to completion. Japan gains the 70% Ratio allowing for Ishitaka, Chichibu, and Ryukaku. The construction of four follow-on Myoko-Class CA comes PRIOR to the London Conference.

Circle One Plan (1930)
CA Kako, Aoba, Furutaka, and Kinugasa down-gunned from 8” to 6” CLs
CL Mogami. Mikuma, Suzuyu and Kumano (6”)
CAV Kushiro and Tokachi
CVL Karasu
+2 DD Shiratsuyu-Class

London goes slightly better for Japan. The Flightdeck Cruiser idea is allowed to occur and Japan abuses the Treaty by building Kushiro and Tokachi claiming a lower tonnage then what they actually possess. CVL Karasu builds on Ryukaku and fills out remaining Japanese carrier tonnage.

Circle Two Plan (1934)
CV Hiryu and Soryu as Hiryu-Class
Cruiser Space Open for TWO Ships—Pends on the Mod
CS Mizuho added as 3rd Chitose-Class CS
+2 DD Asashio-Class

Japan KNOWS it is leaving the Treaty system so Soryu and Hiryu are built as true sisters.

Circle Three Plan--BTS Heavy (1937)
CV Shokaku and Zuikaku
CS Nisshin built as CVL
BB Yamato and Musashi
LBC 2 Fuji-Class

Circle Three Plan--BTS Lite
CV Shokaku and Zuikaku
CS Nisshin built as CVL
BB 2 Owari-Class
BC 2 B-65-Class

DD +3 Kagero-Class (not as dummy Yamato-Class Decoys)
No Katori-Class Training Cruisers (old CLs used instead)

Circle Four Plan--BTS Heavy (1940)
2 Shokaku-Class
BB Shinano and Aki
LBC 2 Fuji-Class

Circle Four Plan--BTS Lite
2 Shokaku-Class
BB 2 Owari-Class
CA 2 Niitaka-Class

New Tokoro-Class CL (3x3 6”) replacing Agano-Class (3x2 6”)
No Taiho or Unryu-Class CV

Circle Five Plan--BTS Heavy (1941)
CV 4 Shokaku-Kai
CVL 3 Aso-Class (Tokoro Conversions)
LBC 2 Fuji-Class

Circle Five Plan--BTS Lite
CV 4 Shokaku-Kai
CVL 3 Aso-Class (Tokoro Conversions)
CA 2 Niitaka-Class


Additional/Changed Allied Ships to December 7, 1941

United States
CV Wasp (Yorktown-Class)
CVL King’s Mountain
CVE Langley and Eli
CLV Charlotte, Jacksonville, Anacostia, and Patuxent
BB Washington (Colorado-Class)
BC Constellation (Lexington-Class)
LBC Chesapeake
CA Rome and Burlington
DD +4 Mahan and +4 Farragut-Class
SS +3 Flying Fish-Class, +1 Argonaut-Class, and +1 Narwhal-Class

Following Admiral Platt and Captain Reeves fervent desires, the USN builds its two CLV (authorized under the London Treaty) AND two more. LOTS of other construction added and in the Fleet by 1941.

United Kingdom
BC Renown
CLAA Dido and Argonaut
DD +4 DD
SS +2 T-Class

Netherland East Indies
BB Prins Hendrik and Prins Willem
CL Eendract and Van Heemskerck
DD +4 DD
SS +3 SS

The Dutch arguably gain the most in this scenario. The Japanese increased build-up prods the Dutch to get construction of the Eendract, Van Heemskerck, Batch-3 DDs, and several more SS completed BEFORE the German Invasion. After the Destroyer-for-Bases Deal, Franklin Roosevelts turns—thru Lend-Lease—to the Dutch and offers them the elderly BB’s Texas and New York. The Dutch accept and the battleships are transferred in early-41. Though needing more crew and carrying American ‘volunteers,’ these old battleships give the Dutch some serious teeth.

Should be noted that these additions were all Real Life thoughts and topics prior to Dec 7th.


France
CL Jean de Vienne
DD +3 Le Hardi-Class
SS +4 (2 Pascal-Class and 2 Surcouf-Class)

The French also gain a powerful Battlecruiser TF in Late Spring 1942 with Strasbourg, Dunkerque, CA Algerie, CL Lamotte-Picquet, 3 DD, and 3 SS.

Australia
CAV Melbourne
DD +4 Admiralty S-Class
SS +2 T-Class

New Zealand
CAV Wellington
DD +2 Admiralty S-Class

[John 3rd]

Heavy Cruisers
Changes and Additions BTS-Lite

With the London Treaty coming in slightly different then what happened historically the Japanese do a complete retooling of their cruiser fleet. The marginal Aoba's/Furutaka's are shifted to 6" guns, thus, making them capable light cruisers. The impressive Mogami's keep their 15 6" guns and are not up-gunned. These changes effectively move and/or keep Japan with 8 capable, more modern CLs.

Heavy Cruisers (years built)
1. EIGHT Myoko-Class built: Myoko(29), Nachi(28), Haguro(29), Ashigara(29), Seiki(29), Chishima(30), Miyako(30), and Yoshino(30).
2. FOUR Takao-Class: Takao(32), Atago(32), Maya(32), and Chokai(32)
3. TWO Niitaka-Class: Tone (39) and Chikuma (40)

Japan starts with 14 CAs instead of 16.

Instead of the Tone-Class, the Japanese decide to create a stronger 'command cruiser.' The Niitaka-Class is designed with 4x3 8" guns and heavy Long Lance armament. Displacement surges to 15,000T and are a perfect example of the 'using a few to conquer many' strategy. The first pair are the Tone and Chikuma with two pairs due to arrive in the Fleet in late-42/43 and 44/45. The design for this class of ships was found over in the Ship Bucket site.


Light Cruisers
Changes and Additions

The changes are pretty big for Light Cruisers.

Classes:
Tenryu and Tatsuta are converted to Fast Minelayers.
Kuma, and Tama are also converted into Fast Minelayers.
Kitakami, Kiso, and Oi are Torpedo Cruisers. Net gain of one TT CL here at war’s start.
Nagara-Class: Nagara, Isuzu, Yura, Natori, Kinu, and Abukuma
Sendai-Class: Naka, Sendai, Jintsu, Niyodo, Ishikara, Minase, Ayase, and Otonase
Yubari-Class: Yubari
Furutaka-Class: Furutaka, Kako, Aoba, and Kinugasa 3x3 6"
Mogami-Class: Mogami, Mikuma, Suzuya, and Kumano 5x3 6"

The Tokoro-Class is authorized to replace the old Nagara/Sendai-Classes. Initially a run of 12-14 is planned but that is changed once war begins. That number changes during the war as 7 are built and 4 more converted into the Aso-Class CVL. These CLs have 3x3 6", good Torps, and 8,000T.

Total pre-war CLs is 26 (2 as ML—2 as Training Cruisers) with 7 building.