During the 156th Defense Project Promotion Committee meeting on August 18, South Korea’s Defense Acquisition Program Administration (DAPA) decided to allocate approximately 595.68 million USD for a comprehensive upgrade of the in-service KSS-II Son Won-il class submarines. Additionally, 320.17 million USD will be invested in the Maritime Tactical Data Link project, specifically for the Link-22 upgrade.
KSS-II upgrade program
The first KSS-II Son Won-il class submarine was commissioned in late 2007. With a displacement of 1,400 tons, it surpasses the capabilities of the preceding KSS-I Jang Bogo-class submarine in underwater operations. This is attributed to its AIP (Air Independent Propulsion) system and its ability to fire the Hyunmoo-III cruise missiles, which can strike targets up to 1,000 km away. The technology behind the KSS-II was derived from the German Type 214 submarine.
The upgrade program aims to enhance the operational capability of the KSS-II submarines currently in service. This will be achieved by replacing outdated systems, such as the combat management system (CMS) and sonar, with the latest indigenous equipment. An investment of approximately $595.68 million USD is allocated for this project, which is slated to run from 2025 to 2036. Through this upgrade, the survivability and combat capability of the KSS-II submarines are expected to improve, bolstering their capacity to monitor and deter potential threats for years to come.
About the Son Won-il class (Type 214)
The Son Won Il-class were acquired as part of the KSS-II program and is based on Type 214, a diesel-electric submarine developed by Howaldtswerke-Deutsche Werft. The vessels, which are named after the ROK Navy’s first chief of naval operations, Admiral Son Won-il, were a major milestone due to their use of the air-independent propulsion system.
Of the nine submarines in the ROKN’s inventory, the first three were built by Hyundai Heavy Industries (HHI) with the remainder being split between HHI and Daewoo Shipbuilding & Marine Engineering (DSME, now known as Hanwha Ocean). The first vessel was commissioned in 2007. The last vessel of the class, the ROKS Shin Dol-seok, entered service in 2020.
Son Won Il-class Specifications:
- Displacement: 1,690 t surfaced / 1,860 t submerged
- Length: 65 m
- Beam: 6.3 m
- Draught: 6 m
- Weapons: 8 x 533 mm torpedo tubes, 4 subharpoon-capable
- Propulsion: 2 x MTU 16V-396; 2 x Piller; AIP system: 2 x HDW PEM; 1 x Siemens Permasyn (2.85 MW)
- Speed: 10 knots surfaced; 20 knots submerged
- Range: 12,000 nautical miles surfaced; 420 submerged
- Crew: 27
Ongoing KSS-I upgrade
The ROK Navy is currently enhancing the capabilities of its older attack submarines in service: The KSS-I Jang Bogo-class. This class is a variant of the Type 209, originally constructed by the German submarine manufacturer Howaldtswerke-Deutsche Werft. The first ship of the KSS-I class was built in Kiel, Germany. However, starting with the second ship, assembly and construction took place in Korea. With a displacement of 1,200 tons, the KSS-I was the ROK Navy’s inaugural attack submarine. First commissioned in 1992, these submarines encountered maintenance challenges due to imported parts that were either discontinued or difficult to procure.
To address these challenges, the ROK Navy initiated an upgrade program for the KSS-I submarines. Known as “performance improvement program” or “PIP”, it incorporates indigenous equipment. This included a new CMS developed by LIG Nex 1, the addition of a Towed Array Sonar System (TASS), and an enhanced attack periscope. Following the PIP, the ROK Navy’s assessment revealed that the submarines now have a detection range that is three times more effective against low-frequency targets and a target tracking capacity that has quadrupled. In a recent development, Hanwha Ocean completed the upgrade of the KSS-I Yi Jong-mu (SS 066) last month, and it now awaits delivery to the ROK Navy.
KSS-II Maritime Tactical Data Link (MTDL) Link-22 upgrade
The Maritime Tactical Data Link (MTDL) is a digital communication network designed to facilitate real-time sharing and broadcasting of target information detected at sea, underwater, and in the air. This network seamlessly integrates surveillance systems, command systems, and strike systems. Its primary function is to support combined forces in executing coordinated operations against naval warfare, submarine warfare, and ballistic missile defense.
Link-22 upgrade aims to transition from Link-11 to the more advanced Link-22. The KSS-II submarines are a priority to receive the Link-22 upgrade. The committee has decided to shift the acquisition method from foreign procurement to domestic purchase and development. An investment of $320.17 million USD is allocated for this upgrade. DAPA expects that the efficient dissemination of tactical information among combined maritime forces will bolster interoperability between the ROK Navy and allied navies such as the US Navy.
In a recent development, Hanwha Systems secured the contract for the Link-22 development. This contract was awarded by DAPA at the end of last year. Hanwha Systems plans to domestically develop the core components of Link-22, including the data link processor and network control software. The ship CMS and system integration, as well as the command post, are also expected to be integrated with Link-22.