Giant aircraft carriers have a large number of aircraft, strong survivability, and a huge deterrent to enemy countries, but due to the high cost, slow construction speed, long maintenance time and other reasons, the cost performance is not very good. This point is naturally clear to the top of the Japanese Navy, so together with the later improved models, Japan has built a total of four Yamato-class giant aircraft carriers, and whether the main aircraft carrier chooses a heavy aircraft carrier with more performance or a medium-sized aircraft carrier with higher cost performance has also caused a fierce debate within the Japanese Navy.

In this regard, Yamaguchi Tawen, who had not been reinstated at the time, wrote directly to Yamamoto Isoroku and expressed his views to him. Yamaguchi believes that medium-sized aircraft carriers like the Yunlong class seem to be more cost-effective, with 60 standard carrier aircraft, while the Xianghe-class heavy aircraft carrier is only 72, but their cost and construction time are at least 50% higher than that of the Yunlong class; However, heavy aircraft carriers have a huge advantage over medium-sized aircraft carriers, that is, the sortie rate of carrier-based aircraft of heavy aircraft carriers is much higher than that of medium-sized aircraft carriers. Taking these two aircraft carriers as an example, although the total number of aircraft carried by the Yunlong class has reached 60, the maximum number of aircraft that can be dispatched at one time is less than 20, while the Xianghe-class heavy aircraft carrier can dispatch more than 30 aircraft at a time, and even more than 40 aircraft at most, this gap is too big.

Moreover, it must be noted that the sortie rate of aircraft carriers not only determines the offensive (all) and even defensive (most) capabilities of aircraft carriers, but if this value is too small, it will seriously limit the maximum size of carrier-based aircraft formations. With the wireless communication and coordination command capabilities of World War II, an aircraft carrier formation can only accommodate a maximum of five aircraft carriers. Although more than one aircraft carrier formation can be dispatched during a major operation, due to the limitations of wireless communication and coordination command capabilities, as well as aircraft endurance, a flight formation that can achieve full coordination can generally only be composed of carrier-based aircraft in the same aircraft carrier formation. In other words, if each aircraft carrier has less than 20 carrier-based aircraft, then Japan's carrier-based air force will not be able to form a formation of even 100 aircraft (Note 1), even if the aircraft carrier formation is equipped with a full 5 aircraft carriers

At a time when the air defense capabilities of warships of various countries are advancing by leaps and bounds, sending such a small-scale flight formation to attack the enemy's fleet or naval base is almost no different from sending them to death, not to mention that in reality it is rare to be able to complete five aircraft carriers, so the size of the formation is even smaller. As a result, the cost-effectiveness ratio is worse. Just look at the miserable results of the Devil Kamikaze Special Attack Team in history. Lost so many planes, even a capital ship in the real sense of the word (3 escort aircraft carriers were sunk, but although the escort aircraft carrier was named an aircraft carrier, it was actually not as expensive as a 10,000-ton cruiser. Historically, the United States has produced 50 ships in a year. The actual combat capability is less than one-tenth of that of a real aircraft carrier, that is, an aircraft carrier of the fleet) did not sink it

However, the sortie rate of Shuanghe is more than 30 aircraft. There are more than 100 aircraft in three ships, and the actual combat effectiveness is several times stronger than that of the Yunlong-class medium-sized aircraft carrier with less than 20 aircraft? And for a weapon, the actual combat effect/cost is the biggest cost performance

Furthermore. The survivability of medium-sized aircraft carriers (including light aircraft carriers with smaller tonnage and even escort aircraft carriers) is also a huge defect; the Yunlong-class aircraft carrier only needs to be hit by a 500-kilogram or even 250-kilogram bomb, and it may lose its combat effectiveness or even sink, while the Xianghe-class heavy aircraft carrier can struggle to drive back to repair even if it is hit by several pieces, which is also of great significance to Japan, which lacks resources and manpower.

Although Yamaguchi had already been sent to China as a military attache in China (Note 2) and seemed to have lost his relationship with the navy, this idea was eventually adopted because Emperor Shohito and Yamamoto Isoroku had always attached great importance to him, and the Japanese Navy's designers not only simplified the design to facilitate mass construction on the basis of the Shozuru-class heavy aircraft carriers, but also optimized some details that were easy to improve. And added new designs such as drifting, so that the performance of the latest heavy aircraft carrier, known as the Yamashiro class, has been significantly improved compared with the Xianghe class, and its standard carrier aircraft number of up to 84 and the sortie rate of 42 carrier-based aircraft make it surpass any active aircraft carrier of the same tonnage on Shijie at this time, and the basic performance parameters of its first ship, the Yamashiro aircraft carrier, are as follows:

Displacement 26,000 tons (standard), 32,800 tons (full load).

Power: 4 ship-based steam turbines, 8 ship-based heavy oil boilers, 160,000 horsepower.

Speed: 34 knots.

Endurance: 10,000 nm / 18 knots.

Firepower: 8 twin 105mm anti-aircraft guns, 8 twin 40mm anti-aircraft guns, 8 twin 20mm anti-aircraft guns, 12 single 20mm anti-aircraft guns.

Carrier-based aircraft: 84 (standard) / 108 (maximum).

Crew: 1750 people.

Note 1: Historically, the United States was able to dispatch an astonishing formation of 1,000 planes in the late stage of World War II, on the one hand, because there were already a large number of ground airfields available at that time, and the aircraft sortie rate at land-based airports was far from comparable to that of aircraft carriers, and on the other hand, because the American planes in the late stage of World War II generally had an amazing endurance, and the United States had deep pockets and did not care about wasting fuel, so it could merge two batches into one batch.

Note 2: After the setback in the South China Sea, Yamaguchi Tawen was fiercely attacked by public opinion in Japan, and later China sent the captured British aircraft carrier Ark Royal to Japan for maintenance, and asked the Japanese government to send people to help China train carrier-based aviation and command and ground staff on the aircraft carrier.

The Red Party Central Committee was not unaware that Yamaguchi Tashi was engaged in espionage work after coming to China, but considering that he was still very dedicated to teaching the officers and men of the first aircraft carrier formation of the Chinese Navy, he only strengthened secrecy and did not arrest or expel him. But the most profitable thing is actually the German Far East Fleet that follows the light by the way, without the guidance of Japanese instructors such as Yamaguchi Tawen, the two German aircraft carriers do not know when they will be able to form combat effectiveness, after all, for aircraft carriers, it is far from enough to have good pilots (to be continued......