ROKS Sejong the Great (DDG-991)

The Story of King Sejong the Great of Korea (DDG-991)

ROKS King Sejong the Great (KD-III) (DDG-991) is the capital ship of the South Korean guided-missile destroyer class of the same name. Six of these ships are planned (three completed and commissioned in 2016) and are comparable to the U.S.

Navy's Arleigh Burke-class ships, except that the South Korean design has a larger displacement and a larger missile load. The ships were built under the Hyundai Heavy Industries (HHI) brand and named after the fourth king of Korea, the Joseon Dynasty (1397-1450), who is credited with creating the Korean alphabet.

China's growing ambitions in the South China Sea and the persistent threat of war in North Korea have forced South Korea to maintain a large military force, including a strong navy. The composition of the service is fairly modern, heavily influenced by American design and combat philosophy to align the two allies when another bloody war breaks out against the North.

King Sejong the Great is a step in the right direction by giving the South Korean Navy (ROKN) a lethal missile weapon to deploy - part of an all-out war with North Korea would be to suppress its naval power in the air to deny and destroy the interior positions and infrastructure.

The destroyers of any modern navy are fast, agile ships designed for a multi-mission mindset, with offensive and defensive capabilities as part of their genetic makeup. These ships are often armed with large numbers of missiles to deal with distant air, land and sea targets, and cannons for more conventional local defense.

These ships can operate independently or as part of a maritime workhorse, giving them tactical flexibility and strategic value.

King Sejong displaces 8,500 tons under standard load and 11,000 tons under full load. It has a length of 165 meters, a beam of 21.4 meters and a draft of 6.25 meters - the latter giving it the quality to operate in shallower waters close to the coast.

Its propulsion system consists of 4 General Electric LM2500 engines driving two shafts in a COGAG (Combined Gas and Gas) arrangement - two gas turbines connected to a single shaft with gearbox allowing one or both engines to run simultaneously - a Proven fuel-saving measures. This gives the vessel a speed of over 30 knots and a range of up to 5,500 nautical miles.

Internally, the warship had a crew of 300, possibly 400 in war conditions. The AN/SPY-1D(V) Multifunction Radar Kit controls the main sensor and processing components. The AN/SPG-62 is used as the fire control radar and the DSQS-21BZ is used as the hull sonar. The dragged array is an MTeQ cell.

LIG Next1 SLQ-200K "Sonata" as electronic warfare (EW) kit for ships.

In terms of weapons, King Sejong had a series of Mk 41 Vertical Launch Systems (VLS) with a total of 80 cells for SM-2 Block IIIB and IV (RIM-66 standard) medium-range surface-to-air missiles. They are paired in 48 and 32 units, with one mounted on the front and the other mounted on the rear.

Another 48-cell array houses 32 x Hyunmoo III cruise missiles for engaging land targets and 16 x K-ASROC Red Shark anti-submarine missiles for countering underwater threats. Also carried six K745 LW Blue Shark torpedoes. The 5-inch Mk 45 Mod 4 gun mounted on the turret adds a more traditional attack system to the warship and is located in a traditional location on the foredeck.

Remotely controlled aerial threats such as cruise missiles, drones and aircraft. All in all, this gave Sejong the Great a reasonable range against almost any maritime threat to the battleship - be it air, sea, or natural threats beneath him.

In the aft position is a full-service helipad with hangar space for two Sikorsky SH-60 (or similar) Seahawk naval helicopters. These systems remain on board, expanding the eyes and ears of warships by carrying advanced sonar and radar equipment and anti-ship/anti-submarine weapons.

Helicopters can also provide better horizon views. The landing site has additional helicopter space in addition to the two enclosed systems, essentially allowing the warship to deploy a total of three rotorcraft in extreme situations.

The helipad can also accommodate support helicopters and rotary-wing unmanned aerial vehicles (UAVs) if required.

King Sejong the Great was still in service in June 2016, assisted by sisters ROKS Yulgok Yi I (2010) and Seoae Ryu Seong-ryong (2012).

Specification

Basic

Roles

Dimensions

Weight

Performance

Performance

Armor

Wing