South Korea launches second KSS-III Batch-II submarine

Hanwha Ocean launched Seo Hui, the second KSS-III Batch-II submarine for the Republic of Korea Navy, at its Okpo shipyard in Geoje on November 3, 2026. The 89m, 3,600-tonne boat combines hydrogen fuel-cell air-independent propulsion with domestically developed lithium-ion batteries to increase submerged endurance and high-speed operating duration. It carries 10 vertical launch tubes for submarine-launched ballistic missiles, compared with six on Batch-I boats, and improved combat-management and sonar systems. Construction follows a KRW985.7 billion contract awarded in 2021, with the keel laid in July 2024, under a three-boat Batch-II programme.