Japan launches fifth Taigei-class submarine

Chogei , the fifth Taigei-class submarine on order for the Japan Maritime Self-Defense Force, seen here at its launch ceremony. (JMSDF)

Japan has launched another Taigei-class diesel-electric submarine (SSK).

The vessel took to the water at Mitsubishi Heavy Industries' Kobe Shipyard on 4 October, the Japan Maritime Self-Defense Force (JMSDF) disclosed on the same day. It will be in service as JS Chogei once commissioned.

Chogei is the fifth of eight Taigei-class submarines that have either been commissioned, contracted, or approved for acquisition.

First-of-class Taigei was commissioned by the JMSDF in March 2022, while funding for the eighth vessel was approved by the Japanese government in fiscal year (FY) 2024.

The Taigei-class programme seeks to equip the JMSDF with a fleet of SSKs that feature greater underwater endurance when compared with its predecessors.

This is achieved by incorporating the vessels with lithium ion batteries in place of lead-acid cells.

The Taigei class displaces about 3,000 tonnes when surfaced and has an overall length of about 84 m, an overall beam of 9.1 m, and a hull draught of about 8.5 m.

It can accommodate a crew complement of 70 and this includes a separate compartment for female crew members.

The SSK's form factor incorporates an X-configuration stern rudder, which provides the submarine with better manoeuvring capabilities, especially when it is surfaced along shallower waters.

Powered by two Kawasaki 12V 25/25SB diesel engines, the SSK can attain top speeds in excess of 20 kt when dived.

While it has been equipped with bow- and flank-mounted sonars, the SSK is also able to deploy towed array sensors to better detect enemy boats across various thermal layers.