Japan has strengthened its submarine fleet with the commissioning of its fifth Taigei-class attack submarine, JS Chōgei (SS-517), delivered by Mitsubishi Heavy Industries at its Kobe shipyard. The vessel, whose construction began in 2022 and launch took place in 2024, is the second submarine from the facility to enter service under the Taigei program.
The submarine will operate from Yokosuka Naval Base in Kanagawa Prefecture, undertaking a range of missions including anti-ship and anti-submarine warfare, ISR operations, and strategic patrols. Particular focus will be placed on monitoring the Miyako Strait, a key maritime chokepoint in the region.
Developed as the next-generation successor to the Sōryū-class, the Taigei program emphasizes improved survivability, detection capabilities, and power efficiency. The submarines feature a larger and more robust design, along with advanced onboard systems and upgraded propulsion architecture.
Each vessel is 84 meters long, with a displacement of about 3,000 tonnes and a crew capacity of roughly 40. Powered by Kawasaki diesel engines combined with lithium-ion battery technology, the submarine achieves enhanced endurance and operational flexibility, generating around 6,000 horsepower and reaching speeds of up to 20 knots.
Armed with torpedoes and anti-ship missiles, the platform is also expected to support future weapon integration, including hypersonic systems under development. Japan plans to build a fleet of 10 Taigei-class submarines, with all units scheduled for commissioning by 2031.
