The Korean War of 1950-1953 was concluded by a cease-fire, not a peace treaty, and the three powers—South Korea, North Korea and the United States—are still technically at war. A new conflict on the Korean peninsula would see the commitment of a new, reinvigorated Republic of Korea Navy, an aging, weakened North Korean Navy and an American fleet providing the only ballistic missile defense capability for the region.
The balance of naval power on the Korean peninsula has decisively—and permanently—shifted to South Korea and her ally the United States. South Korea’s postwar industrialization has made it possible to take on successively large shipbuilding projects. At the same time, North Korea’s long economic decline has made it seemingly incapable of building warships larger than 200 tons
The two Koreas have different goals in mind. South Korea’s economy is dependent on secure sealanes and as a result the Republic of Korea Navy (ROKN) is building large, high-tech ships for a blue ocean navy. Smaller ships are largely an afterthought but a necessity, given the threat posed by North Korean gunboats.
The North’s Korean People’s Army Naval Force (KPN) has fewer resources but only one overarching mission: defending the Kim regime from outside attack. As a result, North Korea’s navy has built a larger fleet of smaller, low-tech gunboats and forced asymmetrical confrontations with the South.
Looming in the background is the U.S. 7th Fleet, by far the most powerful of the three nations. Based in Japan, the 7th Fleet is capable of projecting air and naval power, and providing region-wide ballistic missile defense from forward-based cruisers and destroyers.
South Korea’s Navy is large and expanding, supported by a local shipbuilding industry that has progressed from smaller surface combatants to large helicopter-carrier type ships. The ROKN is emerging as a significant naval force, capable of projecting power beyond the Korean peninsula into the larger Asia Pacific region. In wartime, the ROKN would be tasked with keeping the shipping lanes clear, providing air defense, minesweeping, rear area security, and supporting the Republic of Korea Marine Corps.
The ROKN has 68,000 personnel, 120 ships and 70 aircraft. Despite having fewer ships, by tonnage the ROKN exceeds the North Korean Navy. The ROKN is structured similarly to the U.S. Navy, with three fleets (First, Second, Third) and is headed by a chief of naval operations. Long-range, out-of-area operations are conducted by the newly created Strategic Maneuver Fleet.
The ROKN was originally equipped with former-U.S. Navy ships, particularly nine Allen M. Sumner and Gearing-class destroyers. The first locally built surface warship, the Ulsan-class frigates, were launched in 1980. Since then all surface ships in the ROK Navy have been locally produced.
South Korea’s surface forces amount to 12 destroyers, including 3 Sejong the Great guided-missile destroyers. The Sejong the Great ships are equipped with SPY-1D Aegis radar and are nearly identical to the American Arleigh Burke-class, each carrying eight Harpoon or Hae Seong anti-ship missiles, 128 vertical launch cells for Enhanced Sea Sparrow and SM-2 MR air defense missiles, one 5-inch gun, one Goalkeeper close-in weapons system, one Rolling Airframe Missile system, six 324mm torpedo tubes, and 2 Super Lynx ASW helicopters.
The destroyers were built without Aegis Ballistic Missile Defense (BMD) capability: they can track but not engage ballistic missiles. This was a curious omission, considering the ballistic missile threat from North Korea.
Next up are six general-purpose destroyers of the ROKS Chungmugong Yi Sun-Shin class, which mount eight Hae Seong missiles, 32 vertical launch cells for SM-2MR missiles, one 5-inch gun, one Goalkeeper CIWS, one RAM system, six torpedo tubes, and 2 Super Lynx ASW helicopters. South Korea will build another six equipped with the Aegis radar system between 2019 and 2026.
The three older destroyers of the Gwanggaeto the Great class round out South Korea’s destroyer fleet. South Korea’s first locally built-destroyers, the ships mount 16 Sea Sparrow air defense missiles, eight Harpoon missiles, one Oto-Melara 5-inch gun, one Goalkeeper, six torpedo tubes, and 2 Super Lynx ASW helicopters.
South Korea’s frigate force consists of nine Ulsan-class frigates. Constructed from the early 1980s to 1990s, the ships are largely gun-based, with a single 76mm Oto Melera gun, eight Harpoons, four twin 40mm guns, and three twin 30mm guns. Anti-submarine armament is in the form of six torpedo tubes and two depth charge racks. The Ulsan class is to be replaced with six ships of the new Inchon-class frigate. Currently under construction, the Inchon class will displace 2,000 tons and have the armament of the Gwanggaeto the Great class, minus Sea Sparrow missiles.
Once numerous, the ROK Navy’s fleet of corvettes appears destined for retirement. Twenty-one corvettes of the Pohang class were built starting in 1985. Displacing 950 tons, the corvettes are equipped with two Exocet or Harpoon missiles, one 76mm gun, twin 30mm guns, six torpedo tubes, and two depth charge racks. The class is gradually being retired or exported to foreign navies.
South Korea has a large patrol craft force consisting of 74 Chamsuri (Dolphin) class patrol craft. Each weighs 113 tons, is capable of 34 knots and is armed with a variety of 40mm and 20mm guns. The Chamsuri class is being replaced with at least 20 Gumdoksuri “patrol killer” boats, which weigh 440 tons, mount four Hae Seong anti-ship missiles, one 76mm gun, and two twin 40mm guns.
South Korea has maintained since the early 1990s a force of nine German-made Type 209 submarines. Displacing 1,100 tons, the Type 209s are capable of 11 knots surfaced and 22 knots submerged, and have an endurance of 50 days. Armament consists of SUT Mod.2 torpedoes or Sub Harpoon missiles.
The Type 209 fleet is being supplemented with another nine submarines of the Type 214 class. Built in South Korea with German technical assistance, the submarines are 70 percent larger than the Type 209 class, but have roughly the same performance and armament. The 214 ships will also feature an air-independent propulsion system. Indonesia has signed an order with shipbuilder Daewoo for three submarines, to be delivered by the first half of 2018.
South Korea’s amphibious fleet is getting a major upgrade with the construction of three Dokdo-class helicopter carriers. Displacing 13,200 tons, each has a full-length flight deck with two elevators and a well deck. The ship can support 10 UH-60 Blackhawk helicopters and 2 locally made LSF-II hovercraft (virtually identical to U.S. Navy LCAC hovercraft). Internally it can carry up to 700 troops, 10 trucks, six tanks, six AAVs, and three howitzers. One ship, Dokdo, has been built, another has been funded, and a third is anticipated.
The Republic of Korea Marine Corps (ROKMC) numbers 25,000 personnel, divided into two divisions, the 1st and 2nd Marine Divisions and the 6th Marine Brigade. Both divisions are organized along lines similar to U.S. Marine Corps divisions, with three infantry regiments, an artillery regiment, tank battalion, and assault amphibian battalion. The ROKMC is supported by 124 AAV7A1 assault amphibian vehicles, 50 K1A1 tanks, and locally produced K-9 and KH-179 howitzers.
Korean People’s Army Naval Force
The Korean People’s Army Naval Force (KPN) numbers approximately 46,000 active personnel and 420 vessels, ranging from coastal submarines to harbor patrol craft. Unlike the Republic of Korea Navy, which is capable of significant power projection in the Asia-Pacific, the KPN is a “brown water navy” confined to coastal defense and operations in littorals of the Korean peninsula.
The KPN’s headquarters is in Pyongyang and controls two fleets: the Yellow Sea Fleet (west coast) and the East Sea Fleet (east coast). During wartime, the KPN would be tasked with amphibious lift, support for intelligence and reconnaissance operations, mine warfare, coastal defense, and rear area security.
North Korea, facing a declining economy, has focused its navy on three areas: small patrol craft, miniature submarines, and intelligence collection ships. The decline has left North Korea with a navy weak in the traditional sense, but still capable of accomplishing key missions.
North Korea has made the most of the KPN by conducting asymmetrical operations against the ROK Navy. Although a fleet largely armed with machine guns, light cannon and artillery rockets, the KPN has repeatedly forced confrontations between its diminutive surface force and equivalent ROK Navy vessels. The sinking of the corvette ROKS Cheonan in 2010 by midget submarine is another example of this. This has rendered larger ROK Navy ships ineffective in ship-to-ship operations against the KPN.
North Korea’s small boat fleet consists of 10 Soju-class guided missile patrol boats, North Korean copies of the 1950s-era Soviet Osa-1, with four SS-N-2A Styx anti-ship missiles. It also has less than ten patrol craft over 200 tons, and several dozen craft in the 40 to 80 ton range. Armament consists of 85mm guns, 57mm to 30mm light cannons, heavy machine guns, and even BM-21 rocket launchers adapted for the anti-ship role. Almost all are at least 30 years old, and two reportedly sank in naval exercises last year.
North Korea’s submarine program is centered around a class of mini submarines code-named Sang-o (Shark) by U.S. intelligence. The Sang-o class displaces 295 tons and can travel at 7 knots on the surface, or 8 knots submerged. Two versions exist: a standard attack submarine armed with four torpedoes and 16 mines for the KPN and an infiltration version used by the state intelligence agency’s Reconnaissance Bureau.
A Sang-o submarine was involved in the 1996 “Gangneung incident,” in which an infiltration version of the submarine, along with fifteen North Korean intelligence operatives, landed south of Gangneung, South Korea. After the submarine grounded near shore, the operatives killed the 11-man crew and attempted to return to North Korea over land. Thirteen were killed during a manhunt by South Korean forces, with one captured and another presumed to have successfully exfiltrated to North Korea.
There are up to 38 Sang-o submarines in service. A new, improved version nicknamed Sang-o II entered service in 2011. The improved class is slightly lengthened in the hull and capable of traveling at up to 13 knots submerged.
North Korea has up to 10 Yono-class midget submarines, submersibles displacing 130 tons. The South Korean corvette Cheonanin 2010 was believed to have been sunk by a Yono-class submarine firing a CHT-02D heavyweight acoustic/wake homing torpedo.
North Korea maintains several types of “motherships”—high speed fishing boat-type vessels that are used to conduct covert operations against South Korea and Japan. The total number of such ships is unknown, but 12 are thought to be based at Ch’ongjin, which is responsible for covert operations against Japan, with an overall fleet of three dozen likely.
A variety of vehicles operate from motherships, including swimmer delivery vehicles, semi-submersibles, and midget submarines. Most are indigenously produced and all may have a locally made anti-radar “stealth” paint coating. The motherships accompany the infiltration craft for part of the journey to infiltrate South Korean or Japanese waters.
In December 2001, an unidentified trawler was detected by Japanese intelligence and suspected of being a North Korean mothership. Japan Coast Guard ships gave chase. Warning shots were fired and a shootout took place (video) that resulted with a fire on board the suspected North Korean vessel. All 15 crew aboard were believed to have been killed, with three Japanese coastguardsmen injured.
Finally there are the Kongbang II/III class hovercraft, capable of transporting 40-plus troops at speeds of 40-50 knots. The most modern ships in the North Korean People’s Navy, they are equipped with radars, Gatling guns, and surface-to-air missiles. A handful of Kongbang hovercraft are equipped with anti-ship cruise missiles, 57mm cannon and 30mm autocannon, to take on South Korean Navy ships. North Korea has 130 hovercraft, and according to the authoritative KPA Journal, the “vast majority” are believed the be Kongbang II/III class.
The United States is represented in East Asia by the U.S. Navy’s 7th Fleet. Headquartered in Yokosuka, Japan, the 7th Fleet includes one Carrier Strike Group centered around the USS George Washington and one Expeditionary Strike Group (ESG) centered around the USS Bonhomme Richard. A mine countermeasures squadron controls six minesweepers and a submarine force based at Guam controls three nuclear attack submarines.
In the event of war on the Korean peninsula, the 7th Fleet would provide air support to U.S. and South Korean forces on the ground, as well as conduct air superiority and battlefield interdiction missions. The amphibious force would transport Marine units based on Okinawa, which could serve as a mobile reserve or conduct landings behind enemy lines. Nuclear submarines assigned to the fleet could conduct intelligence missions and cruise missile strikes.
North Korea and Chinese ballistic missiles are a potential threat to South Korea and U.S. forces throughout Asia and as a result ballistic missile defense has become a high priority for the 7th Fleet. South Korea currently has no BMD capability. There are sixteen BMD-capable cruisers and destroyers assigned to the U.S. Pacific Fleet. The majority of the surface combatants assigned to the 7th Fleet at Yokosuka are BMD-capable: the cruiser USS Shiloh and destroyers Stethem, Curtis Wilbur, John S. McCain, Fitzgerald and Lassen.
In early April, Secretary of Defense Chuck Hagel announced plans to forward deploy another two BMD-capable destroyers to Yokosuka by 2017.