Inside South Korea’s New Aegis Destroyer: ROKS Dasan Jeong Yak-yong Joins Three-Axis Defense System

On September 17, 2025, Hyundai Heavy Industries (HD HHI) launched the ROKS Dasan Jeong Yak-yong, the second vessel in South Korea’s next-generation Aegis destroyer program. The launch ceremony took place in Ulsan, marking a significant milestone in the Republic of Korea Navy’s modernization efforts. This advanced warship is poised to become a central component of South Korea’s “Sea-Based Maneuvering Three-Axis System,” a strategic initiative designed to counter North Korea’s growing nuclear and missile threats.

ROKS Dasan Jeong Yak-yong. Photo: HD HHI

The ROKS Dasan Jeong Yak-yong represents a powerful symbol of technological collaboration between South Korea and the United States in the realm of naval warfare. Scheduled for delivery to the Republic of Korea Navy in 2026, the vessel follows the commissioning of the first ship in the class, ROKS Jeongjo the Great, which entered service in 2024. A third destroyer in the same class is expected to be launched by the end of 2027, completing the trio of formidable surface combatants.

Built to project power and defend against a wide spectrum of threats, the Jeongjo the Great-class destroyers are among the most capable in the region. The ROKS Dasan Jeong Yak-yong boasts a standard displacement of 8,500 tons and a full load displacement of 10,000 tons, placing it firmly in the category of large surface combatants. Measuring 165 meters in length and 21.4 meters in beam, the ship’s imposing dimensions reflect its multi-role capabilities and endurance.

The destroyer’s propulsion system is based on a Combined Gas and Gas (COGAG) configuration, featuring four General Electric LM2500 gas turbines. These engines drive two shafts and generate a total of 100,000 shaft horsepower, enabling the vessel to exceed speeds of 30 knots. With a range of 5,500 nautical miles and an endurance of 30 days, the ship is well-suited for extended deployments across the Indo-Pacific region.

Accommodating a crew of 300 personnel, the ROKS Dasan Jeong Yak-yong is designed for sustained operations in high-threat environments. Its sensor suite includes the AN/SPY-1D(V) multi-function radar, a cornerstone of the Aegis Combat System, and the AN/SPG-62 fire control radar for precision targeting. For undersea warfare, the ship is equipped with the DSQS-21BZ-M hull-mounted sonar and the SQR-220K towed array sonar system, providing robust anti-submarine capabilities.

To enhance situational awareness and threat detection, the vessel incorporates the Sagem Infrared Search and Track (IRST) system. Electronic warfare is handled by the LIG Nex1 SLQ-200K Sonata suite, which offers advanced countermeasures and decoy capabilities. These systems collectively ensure that the destroyer can operate effectively in contested maritime environments, where electronic and asymmetric threats are prevalent.

The ship’s armament is equally impressive, beginning with a 127 mm Mk 45 Mod 4 naval gun capable of engaging surface and air targets. Close-in defense is provided by a 30 mm Phalanx CIWS, designed to intercept incoming missiles and aircraft at short range. For offensive operations, the destroyer carries eight SSM-700K Haeseong anti-ship missiles, offering precision strike capabilities against enemy vessels.

A key feature of the ROKS Dasan Jeong Yak-yong is its vertical launch systems, which provide a versatile platform for a wide array of missiles. The ship is outfitted with a 48-cell Mk 41 Vertical Launch System (VLS), capable of deploying SM-2 Block IIIB, SM-3, and SM-6 missiles for air and missile defense. Additionally, a 16-cell Korean Vertical Launch System (K-VLS) supports indigenous weapons such as the K-SAAM, K-ASROC Red Shark, and Haeryong Tactical Surface Launch Missiles for land attack missions.

Further enhancing its layered defense, the destroyer includes a 24-cell K-VLS II system designed to launch Cheongung 3 long-range surface-to-air missiles. This configuration allows the ship to engage multiple threats simultaneously, from ballistic missiles to hostile aircraft and surface targets. The integration of both U.S. and Korean missile technologies underscores the interoperability and strategic depth of the vessel’s combat systems.

The ROKS Dasan Jeong Yak-yong also supports aviation operations, with facilities for two helicopters—either Super Lynx or MH-60R Seahawk models. A dedicated hangar and helipad enable the ship to conduct anti-submarine warfare, search and rescue, and surveillance missions with extended reach. These airborne assets significantly expand the destroyer’s operational envelope and flexibility in joint maritime operations.

As tensions persist on the Korean Peninsula, the deployment of advanced platforms like the ROKS Dasan Jeong Yak-yong signals South Korea’s commitment to maintaining a credible deterrent. The destroyer’s capabilities align with the broader strategic goals of the Republic of Korea Navy, which seeks to enhance its blue-water operational capacity and contribute to regional stability. With its cutting-edge systems and formidable firepower, the vessel is well-positioned to play a pivotal role in future maritime security operations.

The launch of this second Aegis destroyer also reflects South Korea’s growing defense industrial base and its ability to produce world-class naval assets. Hyundai Heavy Industries, as the builder, has demonstrated its expertise in constructing complex warships that meet the rigorous standards of modern naval warfare. The collaboration with American defense firms further strengthens the technological foundation of the program and ensures compatibility with allied forces.

By Trap of War Staff