The ROKN KDX-III destroyer ROKS Sejong the Great (DDG-991). Photo c/o US Navy.













The South Korean Defense Acquisition Program Administration (DAPA) announced on 30 April 2019 that Ministry of National Defense (MND) has approved plans to construct a second batch of three (3) new AEGIS-equipped Sejong Daewang-class KDX-III destroyers worth KRW3.9 trillion (US$3.3 billion), and a second batch of three (3) Dosan Ahn Changho-class KSS-III diesel-electric submarines worth KRW3.4 trillion (US$2.92 billion) for the Republic of Korea Navy (ROKN).





DAPA expects contracts to support the programs to be concluded within the year.





The second batch of KDX-III is expected to be an improvement over the previous design in terms of naval and anti-submarine warfare capabilities. It will utilize the Lockheed Martin AEGIS Block 10 combat system and will be capable of intercepting ballistic missiles as well as an advanced air defense capability.





The ships are designed by Hyundai Heavy Industries (HHI), which was awarded the contract to design in 2016. It is expected that both HHI and Daewoo Shipbuilding & Marine Engineering (DSME), which built the first batch of KDX-III destroyers, will again share the contract to construct. DSME was recently acquired by HHI under a streamlining program.





The current KDX-III are currently the most powerful warship in the ROKN, and are equipped with a 127mm Mk.45 Mod.4 naval gun, a 30mm Goalkeeper CIWS, a Rolling Airframe Missile (RAM) Block 1 launcher, two triple anti-submarine torpedo tubes, four quadruple launchers for the SSM-700K Haeseong anti-ship cruise missiles, an 80-cell Vertical Launching System (VLS) for SM-2 Block IIIB / Block IV surface-to-air /ABM missiles, and a 48-cell VLS for Hyunmoo-3 land attack cruise missiles and K-ASROC Red Shark anti-submarine rockets.





The KDX-III have a full load displacement of 11,000 tons, are 166 meters long, with a beam of 21.4 meters, and a draft of 6.25 meters. They are powered by four (4) General Electric LM2500 gas turbines in Combined Gas and Gas (COGAG) configuration, enabling the ship to a maximum speed in excess of 30 knots and a range of 5,500 nautical miles.





It is also equipped with a hangar facility for two anti-submarine warfare capable naval helicopters, usually either the AgustaWestland Super Lynx or Sikorsky SH-60 Seahawk.











