Hanwha Ocean has rolled out the ROKS Jang Yeong-sil (SS-087), the first Dosan Ahn Chang-ho-class (KSS-III) Batch-II submarine for the Republic of Korea Navy, underscoring Seoul’s drive to expand its indigenous undersea warfare capabilities.
The submarine’s launch ceremony took place at Hanwha’s Geoje-si facility, with top defense and naval officials in attendance. The 3,600-ton diesel-electric vessel will undergo sea trials before joining active service in 2027.
More Power, Range, and Stealth
The Jang Yeong-sil surpasses the earlier Batch-I variants in performance, featuring lithium-ion batteries for longer underwater endurance, higher speeds, and enhanced stealth. It integrates upgraded sonar and combat systems for improved target tracking and engagement, while an auxiliary propulsion system ensures mobility in emergencies.
Noise- and vibration-dampening features further reduce the vessel’s detectability, giving it a tactical edge in contested waters.
A Fully Korean-Built Submarine
Constructed using 100% local technology and materials, the KSS-III Batch-II is 89 meters long, 10 meters wide, and capable of reaching 20 knots and traveling 10,000 nautical miles without surfacing. It can operate over 20 days underwater and carries about 50 sailors.
Armed with submarine-launched ballistic and land-attack cruise missiles, the vessel strengthens South Korea’s deterrence and precision-strike capability.
The Batch-II class follows the successful deployment of three Batch-I submarines between 2021 and 2024, with the entire nine-vessel KSS-III program slated for completion in the 2030s.
