The launching ceremony of Japan's "Thunder Whale" submarine is held on October 17, 2023.

Recently, Kawasaki Heavy Industries of Japan unveiled design scheme for the next generation of conventional submarines in its "Vision 2030" report. These submarines are being developed to replace the Taigei-class submarines, also known as the "Big Whale", currently in service with Japan Self-Defense Forces (JSDF). Military observer Zhou Weizheng believes that the new submarine will see significant improvements in terms of power system, concealment, and attack capability according to the design scheme.

According to Zhou, Japan's new submarine features three major characteristics. First, it boasts enhanced maneuverability due to the incorporation of a high-horsepower diesel engine developed by Kawasaki Heavy Industries. This engine will further enhance the submarine's maneuvering capabilities underwater.

Secondly, it offers higher concealment. In addition to the mature noise reduction technologies used in the Taigei-class submarines, the new submarine will optimize the hull's shape to further reduce underwater navigation noise and enhance submarine concealment.

Thirdly, the enhanced attack capability is a significant breakthrough in the performance of the new submarine. With the installation of the US MK-41 Vertical Launching System (VLS), it is capable of launching various types of missiles and executing diverse combat missions such as anti-ship, anti-submarine, and land strikes. The overall combat performance of Japan's submarines will undergo a substantial change.

In the proposed design, Japan's next-generation submarine is planned to be equipped with a universal VLS capable of firing long-range cruise missiles. Earlier, Japanese media reported that Japan would advance the procurement of US-made Tomahawk cruise missiles to the year 2025. Zhou Weizheng believes that there might be some connection between the two.

Besides, Zhou believes that Japan's submarines equipped with the universal VLS will completely shed their defensive camouflage and transform into an offensive underwater force. He stated that the Tomahawk cruise missile provided by the US has a range of nearly 2,000 kilometers. If Japan's next-generation submarine is equipped with the US MK-41 VLS to launch Type 12 anti-ship missiles and Tomahawk cruise missiles, it will grant the submarines the capability of long-range land strikes underwater. The establishment of this combat capability and the change in usage principles are highly offensive.

It is understood that Japan's first ship of the Taigei-class conventionally-powered submarine was delivered in March 2022, and the No.4 submarine Raigei, or "Thunder Whale" was launched in October 2023. Less than two years after the Taigei-class submarine came into service, Japan is rushing to roll out its next-generation submarine program. "Japan is accelerating the development of its next-generation submarines to widen the gap with its rivals and enhance its underwater warfare capabilities. Japan's move to accelerate the development of offensive military power deserves high vigilance from neighboring countries," said Zhou Weizheng.

Editor's note: Originally published on military.cnr.cn, this article is translated from Chinese into English and edited by the China Military Online. The information and opinions in this article do not necessarily reflect the views of eng.chinamil.com.cn.