South Korea readies 3,600-ton attack submarine to counter China

South Korea has launched the Jang Yeong-sil (SS-087), a 3,600-ton diesel-electric attack submarine and the lead vessel in the second batch of its indigenous Changbogo-III (KSS-III) program. Unveiled at Hanwha Ocean’s shipyard in Geoje, this submarine represents a significant advancement in South Korea’s naval capabilities, featuring improved sensors, enhanced stealth, longer underwater endurance, and advanced combat systems including the ability to launch land-attack cruise missiles. The vessel, built entirely with domestic technology, underscores South Korea’s strategic goal of defense self-reliance and aims to strengthen the Republic of Korea Navy’s underwater deterrence, particularly in response to regional security challenges posed by China. The Changbogo-III Batch-II submarines build on lessons from the first series by integrating improved propulsion, reduced acoustic signatures, and greater automation for extended deployments. Hanwha Ocean, formerly DSME, leads the construction and has been pivotal in