The Japanese "Kaga" has been refitted.

The Japanese "Kaga" has been refitted.

Japan Maritime Self-Defense Force's "Kaga" sailed out of the dock for the first time after completing the "aircraft carrier modification". "Kaga" is the second Japanese helicopter carrier, namely "Izumo" class No.2 ship. "Izumo" and "Kaga" were originally called "frigates" by the Japanese, but their displacement with a full load of 26,000 tons has already far exceeded the usual 4,000-ton frigates. At first, only helicopters could take off and land, but after the Japanese government revised the outline of the defense plan and decided to buy the American F-35B vertical take-off and landing aircraft, it began the modification of these two Yunyun-class aircraft carriers, mainly involving two aspects.

First of all, the Maritime Self-Defense Force should replace its deck with high-temperature resistant materials. In order to adapt to the F-35B VTOL aircraft, the cloud stage has to face the problem of high engine tail flame temperature. The tail flame temperature of F-35B is very high when taking off and landing, which will cause burns to the deck. However, the original deck of Izumo and Kaga cannot withstand high temperature, and must be modified accordingly. Second, both ships need to remove the trapezoidal section of the bow and replace it with a square section. The main purpose of this modification is to increase the deck area so as to accommodate more fighters. These two revisions are carried out in stages. First, the Japanese refitted Izumo, and invited the F-35B fighters of the US Marine Corps to inspect it. It was found that the effect was good and the scheme was feasible, so Kaga was refitted in March 2022.

Japan estimates that the modification of two helicopter carriers will be completed around 2027. In other words, by 2027, Japan will have two quasi-carriers capable of carrying F-35B fighters. Of course, hardware modification alone is not enough. Japan Maritime Self-Defense Force also needs to upgrade the software of these two warships. It is reported that Japan specially purchased the "Joint Precision Landing System" from Raytheon. The main function of the system is to guide the F-35B that landed on the ship. This system also has the ability to work at night, which enables the "Izumo" class to take off and land day and night. What is the modified "Izumo" level? In short, it should not be underestimated.

One of the characteristics of Izumo and Kaga is that the deck is almost as long as the hull. This greatly increases the number of vertical landing sites on the deck. An interesting statement is that if we only look at the deck area, the Kaga is not much smaller than the American, but if we talk about the displacement, the full displacement of the American is 47,000 tons, while the Kaga is just over 26,000 tons. Even with the modified weight, its displacement will not exceed 30,000 tons. In the case of displacement difference of 6.5438+0.5 million tons. The deck area of "Kaga" is not much smaller than that of "USA". Some people think that it is obvious that the Japanese concealed the true full-load displacement of the Kaga. Actually, this is not the case, mainly because of its design advantages.

Before modification, the Kaga was 248 meters long, and the flight deck was 245 meters long and 38 meters wide. After modification, the length of the deck has not been greatly reduced. We can still use the length of 248 meters. The United States has a displacement of 47,000 tons, 257 meters long and 32 meters wide. The length is slightly longer than that of Kaga, but the width is as much as 6 meters different from that of Kaga. This is a simple calculation. The deck area of "Kaga" is 9400 square meters, which is indeed more than the 8200 square meters of "America" with a displacement of over 65438+100000 tons. The reason why "Kaga" can obtain such a large deck area under the condition of insufficient displacement is mainly due to two characteristics of the Japanese army aboard "Kaga": First, it floats very badly outside the deck. Another point is that "Kaga" completely abandoned the dock used for amphibious operations.

So, does the modified Kaga have technical advantages compared with the Shandong ship? The answer is yes, but the advantage is not great.

First of all, talk about the number of carrier-based aircraft. The number of "Shandong" ships loaded with aircraft carriers should be around 23. So how many fighters can Kaga carry? Kaga's hangar covers an area of about 4,000 square meters, which means that only 12 F-35B fighters can be parked in the hangar. Counting the F-35B parked on the deck, the total number of F-35B fighters that Kaga can carry should not exceed 20. Only from the number of carrier-based aircraft that can be carried, there is almost no gap between Kaga and Shandong. Kaga may still have some advantages in the take-off and landing efficiency of carrier-based aircraft. After all, "Kaga" and "Shandong" use different take-off and landing modes. "Shandong" took off with a ski jump to stop landing, and "Kaga" took off with a short distance and landed vertically. According to the statistics released by Japan's unified staff supervision department, the number of landings in Shandong is about 6 10 in 6 days. On average, there are about 40 sorties a day. If the helicopter is removed, the take-off and landing efficiency of "Shandong" is about 20 to 30 sorties per day.

Because the F-35B fighter has not been deployed on the Kaga. We can only make a comparison with the American lightning carrier "America", which is very similar in function and function. Previously, the United States only carried 16 F-35B fighters when testing the United States. In the test, it can take off and land more than 40 times in about 14 hours. Obviously, this take-off and landing efficiency is slightly higher than that of Shandong. But whether "Kaga" can reach this level is two-sided. Judging from the take-off and landing efficiency of fighters, the gap between the two sides should be small.

From the perspective of carrier aircraft, it is obvious that F-35B has certain advantages in combat performance compared with J- 15 fighter. It seems that Kaga's fighting capacity is not much worse than that of Shantung. Finally, when it comes to logistics, it seems easier to supply Kaga. Because the power used by Kaga is JP-5 aviation kerosene, this fuel is exactly the same as that used by its carrier aircraft. If it is replenished, "Kaga" only needs 1 kind of oil, which greatly reduces the difficulty of logistics replenishment. No matter "Liaoning" or "Shandong", the heavy oil for propulsion, diesel oil and kerosene for power generation taken off by carrier aircraft are obviously more difficult to replenish.

However, with the future service of the "Fujian" ship, Japan's "Izumo" class is completely different from the "Fujian" ship.