Drastically Modified Combined Fleet

Chapter 12 - Circle 3 Plan

For the Imperial Navy, the greatest impediment to military reinforcement was the budget and shipbuilding facilities. There were many things they desired, but without the necessary resources, there was little they could do. Moreover, if the shipbuilding facilities were inadequate, they couldn't assemble a sufficient number of warships, nor could they perform the necessary maintenance on them. The Circle 3 Plan, reluctantly carried out in the somewhat unfavorable situation of withdrawing from disarmament treaties, seemed to embody the impoverished state of Japan.

Therefore, only four main battleships would be constructed under this plan. On paper, they were designated as capital ships, and everyone except those involved believed they were battleships, specifically as replacements for the Fusō-class battleships. However, in reality, they were not battleships but aircraft carriers. Turning them into battleships would be a lie, but as capital ships, it wouldn't be impossible to later argue that they were aircraft carriers. The Imperial Navy, being a bureaucratic organization, was as adept at finding loopholes as officials in other government ministries. Additionally, Japan ostensibly adhered to a parliamentary democratic system, and technically, they were required to notify the Diet of the budget. In a sense, this plan was a last resort due to these constraints. Naturally, several members of the Diet raised questions about the details of the capital ships. However, citing the risk of benefiting other nations through information disclosure, the details were kept classified.

Having escaped the shackles of arms reduction treaties, the construction of the four aircraft carriers allowed them to design without much concern for displacement limits. As a result, these four were built as armored aircraft carriers, a long-cherished dream of aviation enthusiasts. However, from the perspective of avoiding top-heaviness, they did not armor the entire flight deck but only the upper part of the hangar.

On the other hand, the construction of cruisers, the next in line after capital ships, was limited to four Katori-class training cruisers. Though they were called cruisers, the Katori-class adopted a merchant ship structure, with a low procurement cost. The total construction cost of these four was comparable, if not cheaper, than three contemporary destroyers. Thus, it could be said that the construction of combat cruisers was practically zero. Being a financially strained navy, there was no budget allocated for large surface strike vessels. Nevertheless, they did not skimp on the construction cost of training ships for personnel development.

While lacking large surface strike vessels, they had a well-equipped fleet of escort vessels such as destroyers, submarines, and coastal defense ships. The importance of protecting maritime traffic and the difficulty of accomplishing that mission had been learned firsthand through the Russo-Japanese War and World War I. Support vessels like repair ships and generous allocations for aviation assets were also present. The decision not to build any money sinks like battleships and heavy cruisers made these allocations possible. Furthermore, traditional priorities like information communication, and medical hygiene, along with reserves for fuel and ammunition, were adequately included in the budget, along with funds for the development of new weapons like radar and guided weapons.

Memo

Excerpts from the Circle 3 Plan

Shōkaku-class aircraft carrier (sister ships Zuikaku, Amakaku, Kamikaku)

- At the time of completion:

-- Overall length 248 m, beam 31 m

-- Displacement 33.000 tons

-- Flight deck 247,5 m by 33 m

-- Eight boilers, four shafts, 160.000 horsepower, 31 knots

-- Eight twin 12,7 cm anti-aircraft guns

-- Twenty triple 25 mm autocannons

-- Aircraft carried: 78 (about 20 of which are tied to the flight deck open-air), two elevators

The Imperial Navy initially harbored the hope of developing a super-large armored aircraft carrier of around 45.000 tons after the end of the disarmament treaties. However, due to the excessive consumption of resources and the inherent limitation of shipbuilding facilities, it became apparent that, no matter how hard they tried, they could only build up to two simultaneously. Furthermore, it was evident that this would significantly impact the budget for the construction of other vessels.

As a result, the construction of super-large armored aircraft carriers was abandoned, and the construction of the Shōkaku-class, consolidated at 33.000 tons, was pursued. While the overall length was almost the same as the Sōryū-class, the deck was reduced further to alleviate top-heaviness. On the other hand, the overall width increased by five meters, successfully ensuring sufficient internal volume. The hangar extended almost the entire length of the ship, and the lower part was a two-tier system with a width of 20 meters between the front and rear elevators, accommodating approximately 60 aircraft in total. The armor was limited to the upper surface of the hangar, with 20 mm DS steel plates and 75 mm CNC decks. Depending on the altitude, it was claimed to withstand a 500 kg bomb.

Kagerō-class destroyer

- At the time of completion:

-- Overall length 121 m, beam 11 m

-- Displacement 2.200 tons

-- Three twin Type 98 10 cm anti-aircraft guns

-- Four triple 25 mm autocannons

-- Two sextuple 53 cm torpedo tubes (without spare torpedoes)

-- Four boilers, two shafts, 60.000 horsepower, 36 knots

The Kagerō-class destroyer is an improved version of the previous Asashio-class destroyer. The main gun has been changed from the Type 89 12,7cm high-angle gun to the newly developed long 10 cm high-angle gun, with no other significant changes. Similar to the Asashio-class, it has a well-balanced armament for anti-submarine, anti-air, and anti-ship roles. The propulsion system, with considerations for mass production, is excellent in quietness. Additionally, configuring it in a shifted arrangement enhances resistance and survivability. The torpedoes are oxygen torpedoes, extremely powerful with twelve on each side. Moreover, being a relatively large destroyer, additional armament can be easily added, and plans include the provision of numerous single-mount machine guns during wartime. The living quarters were initially designed with the expectation of an increase in anti-air personnel.