The Japan Maritime Self-Defense Force (JMSDF) has commissioned the fifth Taigei-class submarine JS Chogei.

The 3,000-ton submarine was delivered by Japanese shipbuilder Mitsubishi Heavy Industries (MHI).

The ships of this class are successors to the current Sōryū-class submarines of the Japan Maritime Self-Defense Force. The third Taigei-class unit Jingei was delivered from MHI’s Kobe Shipyard in March 2024.

Chogei has a length of 84 metres, a hull diameter of 9.1 metres, and can accommodate a crew of 70 members. Unlike its sister vessels, the submarine also features separate accommodation spaces for female crewmembers.

The ship is a conventionally powered submarine that employs a diesel-electric propulsion system and runs submerged using electricity from lithium-ion batteries.

Compared to the Soryu-class submarines, it features sonar with improved detection capabilities and a quieter hull structure, with a standard displacement of approximately 3,000 tons.

The fourth Taigei-class submarine Raigei was built by Kawasaki Heavy Industries (KHI) and delivered last March.