Sejong the Great-class destroyer

On 20 April 2007, South Korean Chief of Naval Operations announced that the lead ship of KDX-III class destroyers will be referred as Sejong the Great. Sejong the Great (Hangul: 세종대왕) is the fourth king of the Joseon Dynasty of Korea. He is credited with the creation of the indigenous Korean system of writing.[2]

The ship features the Aegis Combat System (Baseline 7 Phase 1) combined with AN/SPY-1D multi-function radar antennae.

The Sejong the Great class is the third phase of the South Korean navy's Korean Destroyer eXperimental (KDX) program, a substantial shipbuilding program, which is geared toward enhancing ROKN's ability to successfully defend the maritime areas around South Korea from various modes of threats as well as becoming a blue-water navy.

At 8,500 tons standard displacement and 11,000 tons full load, the KDX-III Sejong the Great destroyers are by far the largest destroyers in the South Korean Navy, and indeed are larger than most destroyers in the navies of other countries.[3] and built slightly bulkier and heavier than Arleigh Burke-class destroyers or Atago-class destroyers to accommodate 32 more missiles. As such, some analysts believe that this class of ships is more appropriately termed a class of cruisers rather than destroyers.[4] KDX-III are currently the largest ships to carry the Aegis combat system.[5]

Sejong the Great-class destroyers' main gun is the 127 mm/L62 Mk. 45 Mod 4 naval gun, an improved version of the same gun used on other warships from several other nations. Point-defense armaments include one 30 mm Goalkeeper CIWS and a RIM-116 Rolling Airframe Missile Block 1 21-round launcher, the first Aegis platform to carry RAM.[6] Anti-aircraft armament consists of SM-2 Block IIIA and IIIB[7][8] in 80-cell VLS. Block IIIB has added infrared (IR) induction mode to Block IIIA, improving cruise missile interception capability. Anti-submarine warfare armaments consists of both K-ASROC Hong Sang-uh (Red Shark) anti-submarine rockets which has same form to the U.S. ASROC. and 32 K745 LW Cheong Sang-uh (Blue Shark) torpedoes. Anti-ship capability is provided by 16 SSM-700K Hae Sung (Sea Star) long-range anti-ship missile, each with performance similar to the U.S. Harpoon. It is equipped on a navy ship that is built after the late KD-2 class destroyer. Land-attack capability is provided by the recently developed Hyunmoo-3C (Guardian of the Northern Sky) cruise missile, which is similar to the U.S. Tomahawk.

Missile batteries

• Vertical Launching System: 128 cell
  • Mk 41 VLS 48 cells (Fwd)
  • Mk 41 VLS 32 cells (Aft)
  • K-VLS 48 cells (Aft)
• Anti-ship missile launchers:
  • 16 (4x quadruple) launchers

The Sejong the Great-class destroyers are often compared to the Arleigh Burke and Atago classes because they utilize the AN/SPY-1 multi-function radar, have similar propulsion and capabilities. One notable difference between the Sejong the Great-class ships and Arleigh Burkes is the number of VLS cells. Destroyers of the Sejong the Great-class have a capacity of 128 missiles, as opposed to 96 on the Arleigh Burke class and the Japanese Atago-class destroyers. The Sejong the Great class is thus one of the most heavily armed ships in the world,[9] with even greater missile capacity than the Chinese People's Liberation Army Navy Type 055 destroyer[10] (112 VLS cells), or the U.S. Navy Ticonderoga-class guided missile cruiser (122 VLS cells), and considering only surface ships is surpassed only by the Kirov-class battlecruiser with 352 missiles (entire missile load).[11] The four American Ohio-class submarines converted to guided-missile configuration carry 154 cruise missiles each. Another similarity to Arleigh Burke Flight IIA and Atago-class destroyers is the presence of full facilities for two helicopters, a feature missing from earlier Arleigh Burke and Kongō-class destroyers.

These destroyers have the capability to track and monitor missiles launched from anywhere in North Korea. This capability was demonstrated by the tracking of a North Korean missile in April 2009.[12]

On 10 December 2013, the ROKN confirmed ordering three more vessels on the same class. On 10 October 2019, HHI signed a deal to build the first of three 170m long, KDX-III Batch II Aegis destroyers for the Republic of Korea Navy.[15] Under the deal, HHI will deliver the first ship by November 2024.[16]

• List of naval ship classes in service
• List of active Republic of Korea Navy ships

• KDX-III Destroyer
• KDX-III armaments