In the past few months, Japan's anti-submarine capability has improved rapidly due to the help of China and Germany and the training of actual combat, and the Japanese army's land-based aircraft have also been stationed on the islands occupied by the Japanese army, making the total number of Japanese planes in the Pacific Ocean more than 6,000, making the old boat-shaped submarines that the United States and Britain must frequently float are increasingly dangerous, and the number of American submarines sunk in the three months from June to August 1942 alone reached 26. In addition, one ship was forced to surrender after being hit by rockets fired by Japanese planes before it could land. However, even if the anti-submarine forces achieved such results, they still could not offset the huge losses caused by the sinking of 1 aircraft carrier, 3 destroyers, and 79 transport ships of the Japanese Navy, with a total displacement of 420,000 tons

In contrast, the Japanese submarines achieved good results in the operation of breaking diplomatic relations, they sank a total of 195 merchant ships and 18 Allied ships in three months, with a total displacement of more than 760,000 tons, although it was still far from being comparable to the German submarines, but the Japanese submarines lost only three, and this exchange ratio undoubtedly made the Japanese Navy deeply excited.

The main reason why the exchange ratio of Japanese submarines in breaking the diplomatic operation is even higher than that of the experienced German submarine force, mainly because the air and sea supremacy in the main areas of German submarine activities are in the hands of the Allies, which makes it difficult for German submarines to get rid of the threat of aircraft, the number one nemesis. Now that almost all of the U.S. aircraft carriers have been lost, the few islands in the South Pacific are all located near New Zealand, and the range of Japanese submarines is the farthest among all submarines of any country. It can enter the South Pacific to fight in depth, so there is no need to worry about the threat of aircraft at all. Even before the invention of towed sonar, aircraft were the greatest threat to older boat-type submarines, so the mere absence of aircraft was enough to cut the loss rate of Japanese submarines by at least half

But in the end, this is to blame for the fact that the Allies have lost too many Pacific islands, not only the remnants of the Allied forces on Guinea Island who insisted on resisting were forced to surrender to the Japanese army because of the complete lack of supplies after the Solomon Islands changed hands again, and even in the entire South Pacific, only a few islands near New Zealand and Easter Island and other small islands close to South America were temporarily spared, and all other islands that could build large airports fell into the hands of the Japanese army, plus the Nimitz fleet only had one aircraft carrier left and did not dare to fight easily, As a result, the allies lost air supremacy over almost the entire South Pacific.

But then again, Japan was under a concentrated attack by a powerful carrier-based aviation force that reached a maximum of 11 aircraft carriers. The U.S. troops, which had to be fortified everywhere and dispersed, were able to inflict a heavy price on the Japanese with a total of more than 50,000 casualties, no less than 14,000 of them killed, missing, and permanently disabled, and three main divisions were disabled and had to be withdrawn to the country for rearmament. It can already be said that I did my best

In addition to not having to worry about encountering enemy aircraft, the relative shortage of anti-submarine ships, especially those with combat effectiveness (Note 1), which led to the U.S. military's two-line operation, and the previous contempt for the threat of Japanese submarines were also important reasons for the success of the Japanese submarine forces

However, the allies also seem to have reason to rejoice, since the South Pacific is much wider than the North Atlantic. There are also relatively few dangerous sea areas. As a result, Allied ships have a much greater choice of routes than in the North Atlantic. This can undoubtedly significantly reduce the probability of Japanese submarines encountering the ships of the allies. It is precisely because of this that although the exchange ratio of Japanese submarines is very good, there is a clear gap between the absolute results of the battle and the German submarine forces. But. In addition to its submarine forces, Japan also has a powerful main fleet in the South Pacific, including 10 aircraft carriers

In order to lure and at the same time force the Nimitz fleet to leave New Zealand to meet the battle, Yamaguchi Tawen deliberately divided this huge fleet with overwhelming superiority into two, and then operated separately in the South Pacific, one north and one south, because the range of the Zero fighter was extremely long, so the reconnaissance range was also terrifyingly large, and the two fleets spread out in this way, almost cutting off the routes of the Allied ships in the South Pacific, during which many Allied transport fleets and their escort fleets that could not evade were attacked by the Japanese aircraft carrier formation

Although the early appearance of proximity fuses and gun-sighting radars in this time and space has made the hit rate of anti-aircraft artillery fire more than ten times higher than that of the same period in history, and this has greatly limited the role of carrier-based aircraft, as the saying goes, "the road is one foot high, and the magic is one foot high." Through exchanges with the German army and their own summing up and reflection on the early days of the Pacific War, the Japanese Navy gradually found some ways for carrier-based aircraft formations to deal with the American fleet with superior anti-aircraft firepower.

With regard to the massive destroyers and the relatively old thin-skinned light cruisers that the Americans could barely beat, the Japanese followed the Chinese Air Force's method of dealing with their light warships, and let bombers and even some fighters carry aviation rockets specifically to attack those thin-skinned ships, but they did not use the method of attaching external aviation rocket launchers, but chose the guide rail type, so that the planes could recover most of their mobility after launching rockets. It is much more convenient to participate in air combat or to escape than to carry a cumbersome launcher. Of course, the accuracy is relatively a little worse than that of the launcher, but the number of Japanese planes is much more than that of China during the Anti-Japanese War, and the density of rockets can be used to compensate for the loss of accuracy.

Since the firing range of aviation rockets is generally more than 5,000 meters, and the target of warships is very large, the aircraft can completely use it to launch an attack before entering the effective range of the enemy's large-caliber antiaircraft guns, and it does not have to enter the distance of about 3,000 meters, which is the greatest threat of close-to-explosive fuse shells, so that the loss rate of the aircraft can be greatly reduced. As for the power, it is a 280mm diameter aviation rocket, which may not be very effective against large warships, especially battleships, but destroyers with small tonnage and thin armor will have to suffer heavy damage after one shot, and a few more rounds will definitely die

Note 1: Warships are not ready to be put into battle just after they are built, and even if the personnel are veterans, they must first familiarize themselves with them, let alone recruit recruits whose training has not yet been completed, so although the output of anti-submarine ships in the United States has soared, the speed at which new ships form combat effectiveness has not yet kept up. Of course, this is only temporary, and this issue will be quickly resolved as the US mobilization unfolds further (to be continued......