Korea’s KDX-III AEGIS Destroyers

SM-6 ERAM test, 2010

USN SM-6 test
(click to view full)

June 11/15: South Korea has requested the sale of the Aegis Combat System through a Foreign Military Sale. The potential sale of three of the systems, as well as auxiliary equipment, could be worth $1.9 billion and comes weeks after the North tested a “submarine-launched” missile. The ACS comprises the SPY-1 radar, Display System and Underwater Countermeasure System, with the Aegis system also capable of operating in a Ballistic Missile Defense capacity.

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Fresh off of a win to build fiber-optic multiplexing systems for American Arleigh Burke Class DDG 110-112 AEGIS destroyers, DRS Technologies Inc.'s EW & Network Systems unit in Buffalo, NY won a $9.2 million contract to build a fiber-optic network system for the Republic of Korea Navy's KDX-III AEGIS destroyer....
ROKS King Sejong the Great at RIMPAC 2010

(click to view full)

The Korean Destroyer eXperimental (KDX) surface combatant shipbuilding program involves 3 individual classes of ships. The 3 KDX-I Gwanggaeto Great Class ships are called destroyers, but at 3,800 tons, their size and armament more properly rank them as small frigates. The last ship of class was commissioned in 2000. The next 6 KDX-II Chungmugong Yi Sun-sin Class ships are indeed destroyers at 6,085 tons full load, with a hull design licensed from Germany’s IABG, and more advanced systems that include SM-2 air defense missiles. They were commissioned between 2003-2008.

With that experience under their belts, Korea entered the 3rd phase of the program. Their KDX-III King Sejong Great Class destroyers weigh in at 8,500 tons standard displacement and 11,000 tons full load. That’s heavier than the USA’s CG-47 Ticonderoga Class cruisers, making them the largest ships in the world to carry Lockheed Martin’s AEGIS combat system. They will form the high end of South Korea’s Navy, while offering a premium showcase for some of the new weapons and electronic systems developed by South Korea’s defense sector.

The KDX III Sejongdaewang-Ham Class


KDX-III promo video
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The KDX-III is clearly intended to be a multi-purpose destroyer will full air defense, land attack, anti-shipping, and anti-submarine capabilities. It is also being designed with the ability to add tactical ballistic missile defense capabilities, and important consideration if North Korea is your neighbor. At present, however, the ships do not possess AEGIS BMD modifications, or SM-3 missiles. The ROKN has ordered 3 ships so far, and will add another 3 for delivery from 2023 – 2027.

These ships are larger than America’s Ticonderoga Class cruisers, and are Aegis cruisers themselves in all but name. Their range of capabilities falls short in the area of ballistic missile defense, but that could be changed for under $100 million per ship. In every other area, they make a competitive case to be the Pacific region’s leading modern multi-role heavy surface combatant, while providing an important platform for new South Korean weapons.

KDX-III vs. other regional ships


Built by Hyundai Heavy Industries in Ulsan, 415 kilometers (257 miles) southeast of Seoul, the KDX-III King Sejong Class will be significantly larger than the 5,000t KDX-IIs. These ships are 166m / 544 feet long and 21m/ 69 feet wide, and 49m/ 161 feet deep, with a standard displacement of 8,500 tons, and a full load displacement of around 11,000 tons. A set of 4 ubiquitous GE LM2500 naval gas turbines provide main power, giving them a high top speed of 30 knots.

Hangars in the back allow carriage of 2 medium naval helicopters. The ROKN actually uses smaller Lynx family helicopters as their primary anti-submarine warfare platform, including the advanced new AW159 Wildcat.

Key Sensors

Sometimes described as an enlarged and updated DDG-51 Arleigh Burke Class, KDX-III will also use the advanced AEGIS radar & combat system (initially Baseline 7, Phase 1) combination, with the AN/SPY-1D (V) radar and the MK99 system of SPG-62 illuminators, etc.

France’s Sagem provides their Vampir long-range IRST (InfraRed Search and Track) system for passive day and night surveillance of ocean and land targets.

For underwater surveillance, a hull-mounted DSQS-21BZ (ASO 90 family) sonar from Atlas Elektronik is paired with a Korean LIG Nex1 towed sonar.


Fixed weapons will include BAE’s 5-inch/ 127mm MK45 Mod 4 naval gun, a pair of 324mm triple torpedo mounts in KMK 32 configuration, a Raytheon RIM-116B Rolling Airframe Missile Block 1 for short-range air defense, and a 30mm Thales “Goalkeeper” CIWS system for close-in defense against aircraft and boats.

KDX-III ships real firepower lies their array of 128 vertical launch cells, which is slightly more than the American Ticonderoga Class cruiser’s 122 cells. On the Korean ships, these VLS cells come in 2 types.

The standard Mk 41 vertical launch cells are split 48 forward, and 32 aft, for a total of 80. Vertically-launched SM-2 Block IIIA/B surface-to-air missiles handle long-range anti-aircraft duties, and an upgrade to the SM-6 is planned. The ships could also upgrade to ABM-capable SM-3s, if accompanying modifications are made to the radar and combat system, but South Korean leaders aren’t interested. Mk.41 cells can also carry a wide variety of other payloads, including quad-packed RIM-162 anti-aircraft missiles, vertically-launched anti-submarine torpedoes, or Tomahawk cruise missiles. South Korea currently seems focused on filling them with SM-2s. This will give the destroyers 3-layer anti-aerial protection (SM-2/6, RAM, Goalkeeper).

Weapons variety comes from a 3rd VLS set of 48 aft-mounted “K-VLS” cells, a Korean system that holds locally-designed weapons like Hyunmoo cruise missiles, SSM-700K Haesung anti-ship missiles, Red Shark “K-ASROC” vertically launched rocket-assisted anti-submarine torpedoes, or other compatible weapons.

Passive Defense

The ships are being designed with a number of low-observable features to reduce their radar profile. These measures also include advanced infrared signature reduction methods designed to give it an IR signature far superior to comparable ships, including its U.S. contemporary the DDG-51 Arleigh Burke class destroyer. If that fails, a locally-designed LIG Nex1 SLQ-200K Sonata ESM system helps the destroyers react to and attempt to jam incoming missiles.

The KDX-III Program


KDX-III Destroyer concept
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Official statements said that the name Sejongdaewang-Ham (“King Sejong”) was chosen for the first ship because of this importance in Korean history. Besides supporting the creation of the Korean “Hangeul” alphabet, this 15th century Chosun Dynasty monarch is also known for strengthening the country’s national defense capability.

GlobalSecurity.org estimates that each of the first 3 ships cost about 1.2 trillion won (roughly $923 million equivalent, albeit in pre-2008 dollars).

* ROKS King Sejong’s official delivery to the ROK Navy took place at the end of 2008
* ROKS Yulgok Yi I was supposed to enter service in 2010, but took until 2011.
* ROKS Seoae Ryu Seong-ryong (was Kwon Yul), was commissioned at the end of August 2012.

Then what?

The program had options for another 3 ships, but the March 2010 sinking of the corvette ROKN Cheonan by a North Korean submarine temporarily shifted the ROKN’s focus away from the globe’s blue waters, and back toward its own littoral regions. Rather than continuing to build more KDX-III destroyers, there was talk in South Korea of modernizing the cheaper 5,000t KDX-II light destroyer design, giving the “KDX-IIA” ships stealthier radar and emissions signatures, and adding AEGIS radars and combat systems to give them better anti-aircraft coverage.

That talk died in 2013, with approval of a KRW 4 trillion/ $3.8 billion program to build another 3 KDX-III ships, and field them from 2023 – 2027.

The key consideration when deciding between KDX-IIA light destroyers and cruiser-sized KDX-III was the trade-off between having a larger number of modern ships in the water to handle submarines and Fast Attack Craft, vs. fleet capability for potential ballistic missile defense (BMD) missions. North Korea fields both kinds of threats, but it was the emergence of a territorially aggressive China and its Air Defense Identification Zone (ADIZ) that turned the tide in favor of more KDX-IIIs. The KDX-III’s SPY-1D (V) radar, AEGIS combat system, and long-range anti-air and surface attack missiles make them a potent force for policing large naval territories.

North Korea couldn’t make that a South Korean national priority, but China did. Less than a month after China’s ADIZ was declared, South Korea had declared one of its own, and announced the KDX-III follow-on contract to give their claim more teeth.

The ships have a set upgrade path for missile defense, thanks to the US Navy’s program to retrofit DDG-51 ships, and the KDX-III destroyers should have enough on-board power and available weight/space growth to handle the BMD mission. Current plans call for adding SM-6 missiles, which are scheduled to gain a point defense BMD role in 2015 – 2016. Korea’s size and maritime geography may make that a perfectly appealing prospect, alongside land-based BMD systems with longer reach.

Contracts and Key Events

Contracts are covered where they are public, and traceable directly to the KDX-III program. This is not always true, for instance with weapons that serve on more than one ship type.


SM-6 ERAM test, 2010

USN SM-6 test
(click to view full)

June 11/15: South Korea has requested the sale of the Aegis Combat System through a Foreign Military Sale. The potential sale of three of the systems, as well as auxiliary equipment, could be worth $1.9 billion and comes weeks after the North tested a “submarine-launched” missile. The ACS comprises the SPY-1 radar, Display System and Underwater Countermeasure System, with the Aegis system also capable of operating in a Ballistic Missile Defense capacity.

Nov 5/14: KDDX. South Korea’s Daewoo shows off models of their proposed KDDX follow-on to the KDX-III. Ship size shrinks to 8,000t, and the number of vertical launch cells also shrinks (48 strike-length Mk.41 and 16 K-VLS, from 80/48), but it retains provision for 16 SSM-700K Haesung anti-ship missiles in dedicated launchers, and provision for a Phalanx CIWS or SeaRAM launcher. This preliminary set of attributes helps explain the proposed budget of $3.8 billion for 3 ships, which is actually a bit low for a KDX-III class ship. It also helps that South Korea may possess the globe’s best shipbuilding industry.

“According to a DSME representative at Indo Defence, the KDDX is being developped as a smaller, more compact and more stealthy follow on to the AEGIS KDX-III destroyers. The main requirements from the ROK Navy are lower maintenance and operating costs than KDX-III…”

Many aspects of the ship aren’t finalized yet, including the radar, but the proposed delivery timeframe of 2023-2027 would make America’s developmental AMDR radar a possible addition, allowing the ROKN to keep the Aegis BMD combat system. There is also talk of using other radars, but unless the ROKN wants to abandon Aegis and its ballistic missile defense modes, they would have to be integrated into the same Aegis combat system. Australia’s CEAFAR/ CEAMOUNT active array radars may be able to offer better radar performance and Aegis integration by then, if Australia invests in new frigates quickly enough. Or, the Koreans could try long-time supplier and Samsung partner Thales, who are working with the Dutch to create their own BMD capable radar (APAR & SMART-L) and combat system combination aboard the Mk.41 compatible De Zeven Provincien Class. Sources: Navy Recognition, “DSME showcasing its next generation KDDX Destroyer for ROK Navy at Indo Defence 2014”.

May 26/14: No SM-3s. South Korean official rule out any deployment of SM-3s for now. Defense Ministry spokesperson Kim Min-seok:

“We’ve never considered adopting the SM-3 missiles… Among issues under consideration is how to boost our maritime-based intercepting capabilities, but we’ve not yet reviewed any details…. Intercepting a missile in the ascending stage goes beyond what our military aims at. It is also beyond our capability…. The KAMD [land-based missile defense architecture] has been under development regardless of the U.S. system, and no changes have been made in our position.”

Planned SM-6 missiles will give the ROKN terminal BMD intercept capabilities around 2015-2016 if they add a combat system upgrade, and that seems to be enough. The national KAMD system currently includes Israeli Green Pine long-range radars, ex-German PATRIOT PAC-2 missiles, and an AMD-Cell command and control backbone. South Korea is about to to upgrade its PATRIOT batteries to PAC-3/Config 3, and add SM-6 missiles to KDX-III destroyers. They may also field Cheolmae 4 BMD-capable missiles in future, designed in collaboration with Russia. Sources: Yonhap, “Acquiring SM-3 missiles not an option for S. Korea: defense ministry”.

May 26/14: Weapons. South Korea has been working to resolve problems with its vertically-launched “Red Shark” (Hongsangeo) rocket-boosted torpedoes since a formal complaint was filed in July 2012. They’ve just finished their 3rd consecutive successful test, which has led DAPA to resume production.

About 500 of these ASROC-type weapons have been deployed on ROKN destroyers thus far, but FFX Batch II frigates are also expected to include them in future. Sources: Yonhap, “S. Korea to resume production of homegrown torpedo after quality improvement”.

2011 – 2013

3rd and last ship delivered; KDX-III ships are tougher than contemporaries; Destroyers used to track North Korean rockets; Chinese belligerence ensures more orders.

DDG-991 & USN LHD-6, CG-65

DDG-991, RIMPAC 2010
USN LHD-6 & CG-65
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Dec 10/13: 3 more. The Joint Chiefs of Staff didn’t even wait until Dec 22/13. Shortly after Korea declared its own expanded air identification zone, JCS chairman Choi Yun-hee approves the KRW 4 trillion (about $3.8 billion) plan to field 3 new Aegis destroyers between 2023 – 2027. That price is much more realistic, but note that it’s still about 1/3 less than the USA pays for smaller Arleigh Burke Flight IIA Aegis destroyers.

The ROK MND later confirms that the new ships will be capable of conducting ballistic missile “detection and tracking”, which is more significant than it sounds. Adding that capability involves about $60 million in modifications to radar processing electronics and software, and once it’s installed, the SM-6 missile that South Korea plans to buy will offer last-stage terminal missile defense. It’s much more diplomatic to leave this as an implied capability, but it will absolutely be present, unless the ROKN elects to use an obsolete version of the Aegis system when the ships are built, rather than the AEGIS BMD 5.1+ system that will available by 2020. If South Korea wants to go beyond last-stage terminal defense, it will also have an inherent ability to add that by simply buying SM-3 missiles. Future events will drive that decision.

We’d also like to point out the amusing refusal of China’s Xinhua to mention that Korea’s new ship decision was prompted in part by China’s new ADIZ. South Korea’s MND is diplomatic, but “ocean sovereignty defense” is pretty clear. Sources: South Korea MND, “Additional securement of three Aegis ships by the mid 2020s” | Yonhap, “(EALD) S. Korea to build three more Aegis destroyers ” | China’s Xinhua, “S.Korea to increase Aegis destroyers to six by 2027” | ROK Drop, “South Korea Declares ADIZ That Overlaps With Chinese Zone”.

3 more approved

Dec 1/13: 3 more? Yonhap reports that China’s aggressive Nov 23/13 “East China Sea Air Defense Identification Zone” declaration, which includes key natural gas fields and ROK facilities like Ieodo Ocean Research Station, is changing South Korea’s defense plans.

A proposed $2.8 billion buy of 3 more KDX-III destroyers was probably going to lose out to other priorities, but now it’s an urgent priority for the Joint Chiefs of Staff. The proposal is now expected to be finalized during a Dec 22/13 meeting, and the destroyers are expected to enter service between 2022 – 2028. Note that $2.8 billion for 3 ships would be about half of what the US Navy pays for smaller DDG-51 Aegis destroyers. That would be amazing, given the 40%+ standard cost share for (often foreign) mission equipment vs. the assembled ship.

All this, and F-35s too. Lockheed Martin says Happy Cyber Monday and Merry Christmas to you too, Xi Jinping. Sources: “S. Korea to OK plan to build three more Aegis destroyers: source”

June 11-12/13: SM-6. The Yonhap news agency quotes “a senior government official,” who says that its KDX-III destroyers will have their SM-2 missiles supplemented by SM-6 purchases as of 2016, as part of KAMD. The SM-6 will complement the ROK’s existing SM-2s. By 2016, they’ll be usable as terminal point defense against ballistic missiles, while also providing long-range air defense against enemy fighters, cruise missiles, etc. If the 2016 delivery date is fixed, it implies a 2014 order for SM-6 missiles. It also implies a future system upgrade for the ships, from a standard Aegis combat system to Aegis BMD 5.0.

KAMD would integrate the ROK’s Green Pine radar, PATRIOT missile batteries, naval missile defense assets, and other surveillance systems into a single “kill chain”, reducing Korea’s dependence on American help. On land, South Korea is looking to upgrade its PATRIOTs to the latest PAC-3/Config-3 standard. The question is how compatible that system will be with the USA’s missile defense systems. A working group has been set up with the USA, and findings are expected in early 2014. South Korea hopes to have KAMD v1.0 fully ready by 2020. Sources: Yonhap, “S. Korea to deploy new surface-to-air missiles for Aegis destroyers” | Global Post, “S. Korea aims to establish missile destruction system by 2020”.

Naval BMD OKed

April 5/13: Amidst the standard threats of war that accompany changes in South Korean administrations, the South Korean military has deployed 2 of its KDX-III destroyers to the East and West Seas, as North Korea reportedly prepares to launch a mobile Musudan/ Nodong-B missile from somewhere along the east coast.

The class isn’t equipped for full ballistic missile defense, but it can pick up missile launches and track them for a period of time. Arirang News.

Dec 12/12: An Unha-3 long-range rocket launched by North Korea is detected by a KDX-III destroyer in the Yellow Sea 94 seconds after its 9:51 am launch. The 1st stage passed over the northernmost island of Baengnyeong one minute later and the 2nd stage flew west of Japan’s Okinawa.

North Korea claims that the rocket is part of a space program. Everyone else understands it as an ICBM test vehicle. A similar launch in April 2012 broke apart shortly after lift-off. Korea Times.

Aug 30/12: #3 delivered. The ROK Navy takes delivery of ROKS Seoae Ryu Seong-ryong [DDG-993], at Hyundai Heavy Industries’ No. 6 dockyard in Ulsan. She will be deployed for combat around mid-2013, after a 9-month trial period. Navy Recognition.

KDX-III #3 in service

July 16/12: #2 trials. ROKS Yulgok Yi I [DDG-992], successfully completes at-sea Combat System Ship Qualification Trials (CSSQT) for the ship’s Aegis Combat System, supported by the U.S. Navy and Lockheed Martin.

Qualification took place at the Pacific Missile Range Facility off the Hawaiian island of Kauai. The trials are the final tests of system design, hardware and software integration, ship construction and crew training. The anti-air warfare exercises included manned aircraft raids, electronic attack scenarios and live air-defense engagements. Lockheed Martin.

June 1/11: #2 in service. The ROKN places the 2nd KDX-III destroyer, ROKS Yulgok Yi I, into service after 9 months of test operations, and assigns her to their Navy’s 7th fleet. South Korea’s Yonhap | NTI | China’s official Xinhua.

KDX-III #2 in service

March 24/11: #3 launched – last? The South Korean Navy launches DDG 993 Seoae Ryu Seong-ryong, named after a leading scholar of the 16th century. Hyundai Heavy Industries SVP Park Sang-cheol is quoted as saying that:

“The Seoae Ryu Seong-ryong is quite different from other existing aegis vessels. Over 100 tons of steel are attached on both sides to prevent damage from explosions in and outside of the ship. This system for a destroyer is not seen anywhere else in the world.”

This ship will be the 3rd – and possibly the last – KDX-III destroyer. The ROKN anticipates commissioning the Seoae Ryu Seong-ryong in late 2012, following various sea trials. Operational deployment isn’t expected until mid-2013. After that, the question is whether the ROKN picks up the program’s 3 options, or decides to build a larger number of lighter and less expensive ships. Meanwhile, the Chosun Ilbo reports that the military is thinking of supplementing or replacing the KDX-IIIs’ medium range SM-2 anti-aircraft missiles with the new active-seeker SM-6, once the U.S. finishes developing it. Hyundai Heavy Industries | Lockheed Martin | Ariang TV | Chosun Ilbo | Forecast International | Korea Herald.

Jan 5/11: Aegis. Lockheed Martin Mission Systems and Sensors in Moorestown, NJ receives a $40.6 million cost-plus-fixed-fee letter contract with performance incentives for combat systems engineering and installation and test aboard the “DDG 993 Kwon Yul,” the KDX-III program’s 3rd ship (which was renamed by March 2011). Requirements include the necessary combat systems engineering, computer program development, and ship integration and test support to deliver a variant of the U.S. Navy Aegis baseline 7, phase I computer program and equipment. This contract also funds an integrated test team to assist the Korean shipyard in performing installation and testing of the Aegis Combat System.

Work will be performed in Ulsan, Korea (48%); Moorestown, NJ (44%); Kongsberg, Norway (7 %); and Dijon, France (1%), and is expected to be complete by September 2012. This contract was not competitively procured by US Naval Sea Systems Command in Washington Navy Yard, DC (N00024-11-C-5103, Foreign Military Sales case KS-P-LPN).

2000 – 2010

2nd ship delivered; Red Shark K-ASROC missile ready to add to KDX-III; Software glitch impairs radar tracking.


ROKS King Sejong the Great
(click to view full)

Aug 31/10: #2 delivered. Daewoo Shipbuilding and Marine Engineering delivers the Yulgok Yi-I to the ROK Navy, as the 2nd ship of class [DDG 992]. KBS.

ROKS Yulgok-Yi I

July 29/10: #1 qualified. Lockheed Martin announces that ROKS Sejong the Great successfully completed a 3-week series of Combat System Ship Qualification Trials (CSSQT), at the US Navy’s Pacific Missile Range Facility off of Kauai, HI. During the CSSQT, the ship’s Aegis Combat System faced comprehensive surface, subsurface and anti-air warfare exercises, as well as thorough testing of the system’s tactical data link capabilities. The anti-air warfare exercises included manned aircraft raids, electronic attack scenarios, and live Standard Missile-2 and Rolling Airframe Missile air defense engagements.

March 26/10: Sinking Shock. The Pohang Class corvette ROKS Cheonan is attacked and sinks, killing 46 of the 104 crew members. Subsequent investigation shows that it was sunk by a North Korean torpedo, fired from a submarine with what was apparently complete surprise.

The attack causes South Korea to re-evaluate its defense plans. The FFX project may end up receiving a boost, at the expense of high-end ships like the KDX-III AEGIS destroyers. Wikipedia re: Cheonan | Chosun Ilbo | JoongAng Daily | NY Times || ROK ambassador to US CSIS presentation [PDF] | Korea JoongAng Daily re: force rethink.

ROKS Cheonan corvette sunk

Nov 17/09: Aegis. Lockheed Martin Maritime Systems & Sensors in Moorestown, NJ received a $41.1 million modification to a previously awarded contract (N00024-03-C-5102) for combat systems engineering (CSE), installation, and testing aboard KDX-III Ship 2. This award includes CSE, computer program development, and ship integration and test support to deliver a variant of the US Navy Aegis weapon system Baseline 7 Phase I computer program and equipment to support the construction of the 2nd Korean ship in the KDX-III class. In addition, this contract funds an integrated test team to assist the Korean shipyard in performing installation and testing of the Aegis Combat System.

This contract involves purchases for the Republic of Korea under the Foreign Military Sales Program. Work will be performed in Moorestown, NJ (53%) and Korea (47%), and is expected to be complete by December 2010. The Naval Sea Systems Command in Washington DC issued the contract.

July 20/09: New squadron concept. The Korea Times reports that their Navy plans to establish a strategic mobile fleet of 2 destroyer-led squadrons by February 2010, in a bid to develop blue-water operational capability beyond coastal defense against a North Korean invasion.

Each mobile squadron would initially consist of a KDX-III Aegis destroyer, 3 4,500-ton KDX-II destroyers, and maritime aircraft. That would be augmented by submarines and smaller ships like the FFX frigates, once a forward naval base is finished on the southern island of Jeju, around 2014.

June 22/09: Red Shark ready. The Korea Times reports that the indigenous Hongsangeo (Red Shark) replacement for American VL-ASROC anti-submarine missiles has completed its 9-year, $80 million development program, and will begin deployment in 2010.

The state-funded Agency for Defense Development (ADD) has also worked with Hongsangeo manufacturer LIG Nex1 to develop the conventional Cheongsangeo (Blue Shark) light torpedo and Baeksangeo (White Shark) heavy torpedo. The Red Shark system uses a Blue Shark torpedo, with a rocket booster for vertical launch and added range.

June 3/09: Glitched. As North Korea prepares to test another long-range ballistic missile, The Korea Times reveals quotes an anonymous Navy source, who said that software glitches in its missile tracking radar system may keep ROKS Sejong the Great in repairs. The ship arrived at the Naval Logistics Command in Jinhae, South Gyeongsang Province on May 23/09. According to their source:

“A flaw in the data transmission system linked with the missile tracking radar in the Aegis destroyer was found. Engineers from the Navy and Lockheed Martin are trying to fix the problem and reconfigure the radar system… The Navy has actually not been able to test the Aegis radar’s maximum capability so far due to the software glitch… We’re not sure at the moment if Sejong the Great will be able to participate in detecting a North Korean ballistic missile this time.”

AEGIS software problem

2005 – 2008

Ship #1 from launch to active service; Ship #2 launched; Will the destruction of ROKS Cheonan change South Korea’s naval plans?

DDH-991 launch

DDH-991 launch
(click to view full)

Dec 22/08: Active service begins. ROKS Sejong the Great [DDG 991] enters active service, making it the 94th AEGIS-equipped ship fielded and making South Korea the 5th nation to field such ships.

ROKS Sejong the Great achieved the impressive feat of on-time, on-budget delivery for a first-of-class ship. It was built and tested at Hyundai Heavy Industries (HHI) in Ulsan, Korea and commissioned in Pusan, and completed its combat system test program ahead of schedule. Lockheed Martin.

KDX-III #1 in service

Dec 1/08: Aegis. Lockheed Martin Maritime Systems & Sensors in Moorestown, NJ received a $19.2 million modification to previously awarded contract (N00024-03-C-5102) for AEGIS Weapon System Inter Site Data Link (ISDL) integration efforts and delivery of the Baseline K1.1 Aegis Weapon System computer programs integrating this capability into the KDX-III Sejong the Great Class destroyers.

The contractor shall provide program management, system engineering and computer program development, ship integration and test, and technical manual services. This contract involves purchases for the Republic of Korea under the Foreign Military Sales Program. Work will be performed in Moorestown, NJ (90%) and Ulsan, South Korea (10%), and is expected to be complete by November 2009. The Naval Sea Systems Command in Washington DC issued the contract.

Nov 14/08: #2 launched. The 2nd KDX-III destroyer, Yulgok Yi I [DDG 992], is launched at Daewoo Shipbuilding and Marine Engineering (DSME) in Okpo, Korea. Yi I was a prominent Confucian scholar of the Joseon Kingdom (1392-1910). Korea Times | Lockheed Martin.

Nov 7/08: #1 accepted. ROKS Sejong the Great [DDG 991] has its delivery accepted by the Republic of Korea Navy. Lockheed Martin.

ROKS Sejong the Great

May 25/07: #1 launched. The first KDX-III destroyer, the ROKS King Sejong [DDG 991], is launched in a ceremony at Ulsan shipyard in the southeastern port city. KOIS report | Hyundai Heavy Industries release.

March 1/07: Navigation. DRS Technologies Inc. announces a $7 million contract from the Daewoo Shipbuilding & Marine Engineering (DSME) Co. Ltd. to provide FODMS Navigation Sensor Distributors for the 2nd KDX-III destroyer, ROKS Yulgok Yi I [DDG 992]

2002 – 2005

South Korea picks AEGIS system for KDX-III, Kongsberg ASW system.

Apr 25/05: Fiber network. Fresh off of a win to build fiber-optic multiplexing systems for American Arleigh Burke Class DDG 110-112 AEGIS destroyers, DRS Technologies Inc.’s EW & Network Systems unit in Buffalo, NY won a $9.2 million contract to build a fiber-optic network system for the Republic of Korea Navy’s related KDX-III King Sejong Class AEGIS destroyer.

DRS EW&NS will build the Fiber Optic Data Multiplex System (FODMS), a general purpose, dual-network system that provides data and integrated communications among propulsion and power control systems, steering, navigation sensors, weapons systems, alarms, indicators, bridge systems and the Aegis combat system, and ensures interoperability between legacy systems and off-the-shelf systems. Work will include the development of design documentation and installation drawing, installation and performance testing of the system. Work will commence immediately, and continue through January 2010.

The Special & Naval Shipbuilding Division of Hyundai Heavy Industries Co. in Ulsan, Republic of Korea, awarded the contract. DRS’ news release noted that the company also expects to receive future contracts of this nature, as the ROKN deploys additional KDX-III destroyers.

June 26/03: Aegis. The U.S. Navy today awarded a $267.5 million contract to Lockheed Martin to provide combat systems engineering, computer program development, and ship integration and test support, as part of the U.S Navy and Lockheed Martin’s responsibility to provide the Aegis Weapon System for its KDX-III Destroyer Program. Lockheed Martin’s release adds that the Korean Navy selected the U.S Navy and Lockheed Martin to equip KDX-III with AEGIS “in late 2002.”

June 18/03: ASW combat system. Lockheed Martin and Kongsberg Defence & Aerospace (KDA) announce a $21 million contract today for the KDX-III destroyers’ anti-submarine warfare control system. The contract expands a trans-Atlantic naval business relationship that began with work on Norway’s F310 Fridtjof Nansen Class AEGIS frigates.

June 17/03: VLS. Lockheed Martin announces an initial $67 million contract to continue production, delivery and installation of the MK 41 Vertical Launching System (VLS) for the U.S. Navy. An additional contract option of $129 million to support of Korea’s KDX-III shipbuilding program could raise the contract’s total value to $196 million. United Defense, LP of Aberdeen, SD (now BAE Systems), will be issued a major subcontract to produce major subassemblies for the MK 41 VLS, as will Metric Systems in Fort Walton Beach, FL.

July 25/02: AEGIS picked. Lockheed Martin wins the contract to provide South Korea’s navy with weapons control systems for the 3 KDX-III destroyers, beating European rival Thales SA. The KDX-III will be equipped with the SPY-1 passive phased array radar and AEGIS combat system, rather than Thales APAR active array radar that serves on the German and Dutch F124 air defense frigates.


March 18/02: AEGIS request. The US Defense Security Cooperation Agency (DSCA) announces [PDF] South Korea’s formal request to buy 3 Lockheed Martin AEGIS air defense systems, worth a potential US$1.2 billion, to arm the ROKN’s 3 new KDX-III destroyers.

The order will include 3 AEGIS Shipboard Combat Systems, 3 AN/UPX-29 (V) Aircraft Identification Monitoring System MK XII Identification Friend or Foe systems, 3 shipboard gridlock systems, 3 Common Data Link Management System/Joint Tactical Distribution Systems, 3 MK 34 gun weapon systems, 3 Navigation Sensor System Interfaces; plus testing and combat system engineering technical assistance, computer program maintenance, U.S. Government and contractor engineering and technical assistance, testing, publications and documentation, training, spare and repair parts, and other related support.

The principal contractors will be Lockheed Martin Naval Electronic Systems and Support of Morristown, NJ; Raytheon Company in Andover, MA; General Dynamics Armament Systems in Burlington, VT; and Lockheed Martin Naval Electronics Systems and Support in Eagan, MN. One or more proposed industrial offset agreements may be related to the proposed sale, but that hasn’t been finalized. If the sale does go through, South Korea will need 50 contractor representatives for approximately 5 years, to support integration and testing of the AEGIS Combat Systems.

AEGIS export request

Additional Readings

Background: The Ships

* Republic of Korea Navy – KDX-III Page. Includes both English and Korean text. Note comparison of the USA’s Arleigh Burke, Japan’s Kongo/Atago, and Korea’s KDX-III AEGIS destroyers.

* Navy Recognition – Sejong the Great class Destroyer – ROK Navy: also known as KDX-III, Sejongdaewang class AEGIS Destroyer.

* Wikipedia – King Sejong the Great class destroyer.

* Ask Asia – King Sejong the Great and the Golden Age of Korea.

* Davis Engineering (Sept 2002) – KDX-III Advanced IR Design.

Background: Ancillary Technologies

* Lockheed Martin – AEGIS, Shield of the Fleet.

* Lockheed Martin – Aegis Combat System.

* LIG Nex1 – Lightweight Torpedo (Blue Shark).

* Thales – Goalkeeper – close-in weapon system.

* LIG Nex1 – Surface-to-Surface Missile (Hyun Mu).

* LIG Nex1 – Korean Anti-Submarine Missile (KASM, Red Shark).

* DID – Naval Swiss Army Knife: MK 41 Vertical Missile Launch Systems (VLS).

* BAE Systems – Mk 45 Mod 4 Naval Gun System.

* DID – RAM (Rolling Airframe Missile) Systems: Contracts & Events.

* LIG Nex1 – SLQ-200K Sonata. ESM emissions locator.

* DID – Raytheon’s Standard Missile Naval Defense Family (SM-1 to SM-6)

* Sagem – Vampir NG long-range IRST (InfraRed Search and Track).

* DID – Pining for Control: South Korea’s KAMD Buying ABM Radars, AMD C2. The core of South Korea’s ballistic missile defense system, which will include the KDX-III ships and SM-6 missiles as the naval component.

News & Views

* DID – Pining for Control: South Korea Buying ABM Radars, AMD C2. Green Pine BMD radars from Israel, and advanced command and control infrastructure.

* Navy Recognition (Nov 5/14) – DSME showcasing its next generation KDDX Destroyer for ROK Navy at Indo Defence 2014. Smaller 8,000t follow-on class.

* ISN (May 26/14) – South Korea’s Air and Missile Defence: Below the Threat Level.

* Yonhap (May 26/14) – Acquiring SM-3 missiles not an option for S. Korea: defense ministry.

* The Diplomat (Oct 23/13) – Why South Korea’s Building an Impressive Navy. Note, this was before the China ADIZ provocation.

* Yonhap (Oct 15/13) – S. Korea seeks multi-layered missile defense against North.

* The Diplomat (July 26/13) – South Korea Goes All In On Missile Defense.

* RUSI (March 13/13) – South Korea’s Emergent Missile Defence Capabilities.

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