South Korea’s ambitious, indigenously designed KSS-III submarine program introduces conventionally armed submarine-launched ballistic-missile (SLBM) capabilities and cements the nation’s reputation as a preeminent builder and operator of non-nuclear air-independent propulsion (AIP) submarines.
Nine KSS-III submarines are planned by the early 2030s under the program, which is divided into three batches of three submarines. The three KSS-III Batch I subs, known as the Dosan Ahn Changho class, include the class namesake Dosan Ahn Changho, launched in September 2018 and commissioned on 13 August 2021, followed by sister Ahn Mu (pictured), which was launched on 10 November 2020 and commissioned in April 2023. Daewoo Shipbuilding and Marine Engineering (DSME) at Okpo built the first two submarines. Hyundai Heavy Industries in Ulsan is building the third and final KSS-III Batch 1 unit, the Shin Chaeho. The Shin Chaeho was launched on 28 September 2021 and is scheduled for delivery in the spring of 2024.
Significantly larger than South Korea’s previous generation of German-designed KSS-II/Type 214 submarines, the KSS-III Batch 1 boats have a crew of 50, displace 3,358 tons surfaced and 3,705 tons submerged, and measure 274 feet long with a 31.5-foot beam. Like the older KSS-II, the KSS-III class is powered by diesel-electric with supplemental AIP capabilities using fuel cell technology. This provides top speeds of 20 knots and extended underwater operations lasting as long as 20 days.
The Dosan Ahn Changho class is fitted with an innovative vertical launch system (VLS) abaft the sail. The VLS can carry six conventionally armed SLBMs for land attack. Reportedly named the Hyunmoo 4-4, the non-nuclear SLBMs have a range of 270 nautical miles and were successfully test launched from the Dosan Ahn Changho in September 2021. The class also carries advanced sensors and weapons, including bow, flank, and towed-array sonars and six 21-inch bow tubes for heavyweight torpedoes, such as the new Tiger Shark.
In March 2023 the keel was laid at DSME for the first of three lengthened KSS-III Batch 2 submarines. At 292 feet long, the Batch 2 units will have the same 50-person crew size but are around 20 feet longer than the Batch 1 submarines. Their extended VLS will house ten conventional SLBMs. Notably, the Batch 2 submarines will retain their AIP-capable systems while also incorporating lithium-ion batteries in place of the lead-acid type carried on board the Batch 1 and earlier submarines. This will enable further enhanced underwater endurance and longer battery life cycles. Batch 2 deliveries are set to begin in 2027. In the early 2030s, the KSS-III program will conclude with production of three KSS-III Batch 3 submarines, which are expected to be larger still, and more sophisticated, than the Batch 1 and 2 boats.
