Battering Ram of the Sea

Chapter 57 - New Strength

It was a source of great regret when Truk Island suffered a severe blow from the aerial assault by the US carrier-based aircraft and the naval gunfire from surface vessels. As a result of this, the Imperial Navy had no choice but to move its front lines from Truk to the Marianas or Palau. However, on the other hand, new forces were emerging on the mainland.

Just after the new year, four Unryū-class aircraft carriers were completed. In the Naval Battle of the Marshall Islands that occurred in December 1941, the then 1st Air Fleet lost three carriers, Akagi, Kaga, and Ryūjō, all at once. The Imperial Navy's top brass was in a panic due to the enormity of the losses and rushed to fill the gap.

Since the war had started, what was needed were wartime emergency aircraft carriers that could be built quickly, but the Imperial Navy, which did not have this plan in place, planned to develop four carriers based on the design of the Hiryū as the next best option. The construction of these carriers, which started in January 1942, utilized the engines of cruisers or Kagerō-class destroyers that were in the process of being discontinued to aim for early completion, especially in the most labor-intensive parts of construction. Limiting the number of ships, and the relatively smooth progress of naval escort battles, also played a role, and the Unryū-class aircraft carriers were completed within two years of the start of construction.

Around the same time as the completion of the Unryū-class aircraft carriers, four Kongō-class battleships were also completed after being converted into aircraft carriers. Although this involved a somewhat impure motive of reducing the influence of the gunnery faction by Admiral Isoroku Yamamoto, who was the commander-in-chief of the Combined Fleet at the time of construction, there was still a strong force to counter the significantly enhanced American aircraft carriers.

In addition, slightly later than the Unryū-class and Kongō-class, new aircraft carriers built in the Circle 4 plan were also completed. With a standard displacement of 29.300 tons and 20 mm DS steel plates and 75 mm CNC decks between the fore and aft elevators, these were the first armored aircraft carriers in the Imperial Navy, and they were already designated as the flagship of the Combined Fleet under the name Taihō.

The aircraft to be carried on these carriers is also being updated to new models. The fighter aircraft have been upgraded from the A6M Zero Model 21, which was the mainstay until now, to the Model 53. The engines were changed from the 940 horsepower of the Model 21 to the 1.300 horsepower of the Model 53, which, despite a reduced range due to the change from the Sakae engine to the Kinsei engine, significantly improved acceleration performance due to the higher top speed, climbing ability, and higher torque. Although the bulletproof equipment still does not match the level of American aircraft, bulletproof steel plates and bulletproof glass have been added, and the crew protection capability has dramatically evolved compared to the initial model. As for armament, the 20 mm autocannon was replaced with the long-barreled Mark 2 cannon, and with the successful development of belt-fed magazines, the number of rounds per gun increased to 200. Also, the 7,7 mm machine guns that were previously installed on the nose were removed, and new 13 mm machine guns were added to both wings.

The dive bombers were changed from the D3A to the D4Y Suisei. The Suisei is more than 100 kilometers per hour faster than the D3A and its bomb-carrying capacity has been increased from 250 kg to 500 kg. In addition, unlike land-based bases, the limited maintenance capability on the narrow carrier deck led to the adoption of the air-cooled Kinsei engine for the aircraft of the carrier air squadrons. The Suisei and the Zero both use the same engine, which provides several advantages in maintenance and replenishment. The torpedo bombers were changed from the B5Ns to the B6N Tenzan, which, with one Type 91 aerial torpedo or one 800 kg bomb, has not changed its carrying capacity but significantly increased its range and top speed, to nearly 100 kilometers per hour.

In parallel with the maintenance of aircraft carriers and carrier-based aircraft, the strengthening of escort vessels is also being pursued.

Immediately after the start of the war, construction began on the wartime emergency-type destroyers, with the Yūgumo-class specializing in torpedo attacks as the seventh ship and the Akizuki-class specializing in anti-aircraft warfare as the sixth ship, so nearly 20 of them have already been completed.

These wartime emergency-type destroyers, with the Matsu as the lead ship, although they have a slightly slower speed of less than 28 knots, have the latest listening devices and sonar equipment imported from Germany and have adopted high-angle guns, surpassing the Kagerō and Yūgumo classes in terms of anti-aircraft capabilities.

And, after the training and familiarization of these vessels was completed in June, the US forces invaded the Marianas with a major force. Of course, there was no choice but to confront the Combined Fleet.