Sea Sword-II
Gallery
Overview
South Korean 12 m armed USV for littoral reconnaissance and surface warfare, basis for the ROK Navy's reconnaissance USV.
Sea Sword-II (Haegeom-II) is LIG Nex1's 12 m armed unmanned surface vessel and the foundation of South Korea's naval USV programs. Its low-signature fibre-reinforced plastic monohull has a 3.5 m beam and displaces about 11 tonnes; twin diesel engines driving Kamewa waterjets push it beyond 35 knots, with a range of about 180 nautical miles at 20 knots. The sensor mast combines surface-search radar, a stabilized EO/IR gimbal, laser designation, LIDAR, and wide-area cameras, while a scanning sonar supports underwater search. Armament includes a 2.75-inch guided rocket launcher and a 12.7 mm remote weapon station. Sea trials, including operation in 2.5 m waves, were completed in December 2021, and the design led to a DAPA order for two reconnaissance USVs due from 2027.
Primary Roles
Notes
Published figures: 12 m length, 3.5 m beam, 11 tonnes, twin diesel engines and Kamewa waterjets, more than 35 kn, and 180 nm range at 20 kn (converted to 333 km). Developed with the Agency for Defense Development under a MOTIE/DAPA civil-military program; LIG Nex1 showed the larger Sea Sword-X combat USV at MADEX 2025.
