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SSX-N Korean Atomic Submarine ??

The Ministry of National Defense established the '21~'25 mid-term defense plan 10 August 2020. The plan noted the importance of the surveillance and reconnaissance mission around the Seas and territorial waters on the Korean Peninsula. It called for a response ability reinforced with a 3,000 ton submarine with armed loading capacity, and submersibles improved with 3,600 ton And 4,000 ton submarines. The military announced for the first time the planned construction of a 4,000 ton submarine. Design work will begin in 2025 while some experts speculate the sub may be nuclear powered.

A ministry official said the government plans to load submarine-launched ballistic missiles (SLBMs) on the new submarines, adding that whether they will be nuclear-powered has yet to be decided. “We have in mind 3,600- and 4,000-ton submarines for development, much more advanced than the ones in operation now,” a senior ministry official said, referring to the 3,000-ton Dosan Ahn Changho, the first locally made attack submarines. The official said the ministry was positive that the new submarines would be capable of carrying more ballistic missiles than the existing Dosan submarines, which have six launching tubes.

Nuclear-powered submarines are considered more powerful than diesel submarines because they can stay under water unnoticed much longer. They can also travel much faster. Only six countries including the US and Russia are known to possess them. South Korea initially pushed to build its first nuclear submarine in 2003, amid rising military tensions prompted by North Korea’s withdrawal in the same year from the non-proliferation treaty that prevents the spread of nuclear weapons technology.

But Korea had to abort the mission in 2010 as the International Atomic Energy Agency, backed by the US and countries opposing Seoul’s plan, took issue with it, out of fear it could spark an arms race in the region. To develop nuclear-powered military assets, Seoul would also have to revise a nuclear pact with Washington, under which Seoul is committed to using only a limited level of enriched uranium for nonmilitary purposes only.

Supporters of a South Korean nuclear attack submarine say such vessels can be assigned to patrol around North Korean submarine bases without being detected and trail SLBM-armed subs heading out to sea. It is not evident that nuclear submarines would be superior to advanced non-nuclear submarines in performing such a mission. It is evident that the high levels of uranium enrichment typically associated with submarine nuclear propulsion [typically close to or equal to bomb grade] would provide South Korea with a foundation upon which a nuclear weapons capability could be rapidly constructed.

South Korea could avoid the international restriction by developing a nuclear submarine run by low-enriched uranium, which would not immeditaly incur concerns over military use. Some nuclear submarines, such as those developed by France, can work on 20 percent enriched uranium. The Seoul-Washington nuclear cooperation deal, revised in 2015, would allow Seoul to enrich uranium to a level of 20 percent when using US ingredients. But the agreement disallows the uranium enrichment for military purposes.

The arithmetic of uranium enrichment can be a bit deceptive. Natural uranium contains about 0.72% U235, while bomb grade uranium is enriched to 90% U235. The 20 percent enrichment level requires enrichment by a factor of [20.0% / 0.72%] = 27.7, while enrichment to bomb grade requires enrichment by a factor of [90% / 20%] = 4.5 - so most of the work is already done with enrichment to 20%. The 20% threshold is better than nothing, but it is not a barrier to further enrichment.

The 1999 movie Yuryeong [aka Phantom Submarine or Phantom: The Submarine ] centers on the Phantom, Korea's first nuclear submarine. The movie follows the crew of anonymous sailors controlling the top secret Korean nuclear submarine known as the Phantom. The main character became an unwilling crew member when the government officially erased him from existence. Like Crimson Tide or Hunt for Red October, the film follows the first Korean nuclear submarine out into international waters where it encounters and destroys several Japanese subs in some very well rendered sequences. Armed with nuclear weapons and a crew with no record of existence, it embarked on a do-or-die mission into the deep waters of the Pacific. This movie won six "Academy Awards" in South Korea in 1999.

During the Roh Moo-hyun administration, South Korea launched a clandestine nuclear submarine project in 2003, code-named “362 initiative”. The government anticipated that building one nuclear submarine would cost about 1.3 trillion won ($1.16 billion), about one-fortieth of South Korea’s defense budget in 2017. The project was canceled a year later when the plans became public.

In January 2004 Choson Ilbo journalist Yu Yong-won reported that South Korean military authorities were considering the possibility of developing nuclear powered submarines after 2012. South Korean officials began to discuss the construction of nuclear submarines in May 2003, to be able to deal with "potential security threats from other strong powers in the region following Korean unification." The South Korean Navy was reported to have formed a working group of some 30 specialists to initiate design work on the project.

In August 2004, reporter Kim Yong-sam of the South Korean monthly news magazine Wolgan Choson reported that the Ministry of National Defense had approved concept designs in June 2003. An inter-agency working group for the project was said to include the ROK Navy, the Agency for Defense Development (ADD), and the Korea Atomic Energy Research Institute (KAERI).

According to one report, government officials stated that on 25 January 2004 Defense Department and the navy examined the construction of an atomic submarine positively, based on the report from May 2003. The nuclear propelled submarine of 4,000 ton class (SSX), after 2012, was said to be viewed positively in order for the Korean navy to cope with the threat in regard to the security of neighboring countries such as Japan and China.

Initially for the Korean navy, the German make 214 model submarines (KSS-II) was to lead to the domestic 3,500 ton type conventionally powered submarine (KSS-III), which would lead to the the domestic 4,000 ton model atomic submarine (SSX). In this plan there is a gradual evolution, loading domestic cruise missiles on the KSS-III. The alternative was a schedule in which building the KSS-III is excluded, when the approach which directly builds the atomic submarine is connected to the guaranty of the effective naval arm. If the project had been approved in 2007, and started construction 2~3 years would be needed, with at least 3 planned. Under this plan the first would be commissioned in 2012.

During the Roh Moo-hyun administration, South Korea launched a clandestine military project in 2003 to protect itself from North Korea’s nuclear and missile threats: developing its own nuclear-powered submarines and deploying them by 2020. Dubbed “362 initiative,” the program was derailed just a year later, with classified information leaked to the public and its nuclear activity brought under the scrutiny of UN nuclear watchdog International Atomic Energy Agency.

Secret South Korean military documents were inadvertently published on the South Korean Defense Acquisition Program Administration (DAPA) website when the agency was established on 01 January 2006. DAPA uploaded classified excerpts from Ministry of National Defense weapons development plans, for which over one hundred were classified as "top secret" (level 3) or "no foreign access." The document excerpts on the DAPA website included references to South Korean plans to build three "medium-size next generation" submarines between 2010 and 2022, under the "SSX project." The size of the budget allocation for the submarines (3.074 trillion won - about $3.24 billion) suggested that Seoul was indeed planning to develop nuclear-powered vessels.

The South Korean Ministry of National Defense and DAPA denied any plans to develop nuclear-propelled submarines. On January 9, 2006, DAPA Director Kim Chong-il insisted that there are no plans to develop a nuclear-powered submarine and that it was "absurd nonsense" to suggest that the SSX project submarines would be nuclear-powered.

When the Roh administration launched the submarine program, the then-government anticipated that building one nuclear submarine would cost about 1.3 trillion won ($1.16 billion), about one-fortieth of South Korea’s defense budget in 2017. “South Korea’s atomic energy agency finished its basic design for a nuclear reactor that can be used for a nuclear-powered submarine in 2004,” Kim Si-hwan, who was in charge of developing nuclear reactors for submarines at the Atomic Energy Research Institute, said in an interview with local magazine Monthly Chosun.

As for SSX nuclear propelled submarine of 4,000 ton class, the atomic energy-related systems for the submarine might receive technical aid from Russia. The Korean Atomic Energy Laboratory SMART-P technical verification reactor is a next generation 100 MWt reactor where principal device such as steam generator and pressurizer has settled in one (design life approximately 30 years). It was developed from 2002, and completed in June 2008. As for this experimental reactor, that is one possible prototype for a 4,000 ton KSS-N, the height is 10m and diameter 5m.

One issue is that the atomic submarine would have a nuclear power plant that used Low Enriched Uranium, in order not to violate to the Korean Peninsula denuclearization declaration. The problem is that such fuel would have a relatively short core life, requiring frequent three year refueling. Normally, nuclear powered submarines use uranium enriched to ove 80%, to nearly bomb grade of over 90%.

At present, the construction of a uranium enrichment plant is regarded as tantamount to building facilities to produce nuclear weapons material.

South Korea has concentrated on the peaceful use of atomic energy without pursuing nuclear weapons development while it has operated many nuclear reactors to date. Korea’s nuclear power industry began in the early 1960s with the introduction of a US nuclear reactor. Korea now exclusively relies on indigenous designs for its new reactor builds, and the amount of local content on these reactors has become high. Recently, Korea’s growing capabilities and export ambitions have turned it into a direct competitor with U.S. industry for exports to third countries, most noticeably with UAE, where a Korean consortium beat out GE-Hitachi and Areva for the Barakah tender. 

Although it has developed enough to win overseas contracts to build reactors, in the unequal world of nuclear power Seoul’s nuclear agreement with Washington inhibits its peaceful use of nuclear energy. To produce electricity in a nuclear power plant, 3 to 5 percent low-grade enriched uranium is necessary. But the United States opposes the construction of plants and facilities to enrich fuel material on the grounds that they could be used to produce nuclear weapons.

South Korea and the United States reached agreement on 22 April 2015 for a revision of the so-called 123 Agreement on nuclear cooperation , allowing Seoul to expand its commercial use of nuclear energy. On 15 June 2015 Secretary of Energy Ernest J. Moniz and Korean Foreign Minister Yun signed the successor United States - Republic of Korea Agreement for Civil Nuclear Cooperation, or 123 Agreement, as they are referred to in the United States. The parties agreed to remove the "gold standard" from the original 1974 agreement that legally bound US partners to foreswear uranium enrichment and reprocessing. The new accord also allowed Seoul to produce uranium enriched to up to 20 percent when using US ingredients.

Daewoo Shipbuilding & Marine Engineering DSME (as at April 2015) was designing a nuclear propulsion [surface] ship. The world's first arctic ship with outside temperatures as low as -40°C and has a design temperature of -50°C developed for drilling in the extreme cold environments. The arctic drill ship has a closed derrick based on the monocoque hull specifically designed for the ship's crew to be able to operate effectively and safely while consuming the least amount of energy. The offshore structure that enables drilling in the extreme cold weather conditions was developed to capitalize the resources that became more accessible as the Arctic sea ice is getting thinner due to global warming. The major characteristics of the arctic drill ship are the closed derrick based and the monocoque hull which are specifically designed for the ship's crew to be able to operate effectively and safely while consuming the minimum energy.

Acquiring nuclear submarines is a sensitive issue for South Korea because it could trigger opposition from nations such as the United States and China amid worries about a regional arms race. The ROK Ministry of National Defense said that while the NPT refers to nuclear weapons, it does not appear to specifically restrict development of nuclear-powered submarines. The ministry added that the development of a nuclear sub would not be against International Atomic Energy Agency regulations, either.

Support of nuclear-powered submarines further intensified in August 2016 when North Korea successfully test-fired a submarine-launched ballistic missile. South Korean President Park Geun-hye on 30 August 2016 ordered her military to develop effective measures to counter the North’s increasing nuclear and missile capabilities. “I call upon you to maintain a robust posture to retaliate, to make sure that any attempt by the North at engaging in any form of provocation will lead to the self-destruction of the North Korean regime,” Park said.

By 2016 satellite images of the North Korean naval base near Sinpo showed a launching way and large construction hall in a secure boat basin, that analysts say could be used to build and launch a new ballistic missile submarine. Despite the North’s recent progress, the US-Korea Institute at Johns Hopkins University said it is unlikely that any new SLBM capable vessel would become operational before 2020.

Chung Jin-suk, a leader of ruling Saenuri party has called for the South to deploy its own nuclear powered submarine that can track down and block any incursions from the North. “[I urge] South Korean military to actively consider deployment of nuclear powered submarine which has a capacity to operate underwater for an extended period of time, a high-tech sonar system, and striking power,” he said. The South Korea Defense Ministry said it will look into all options but is not considering a nuclear submarine at this time.

The government promised 18 October 2016 to review a proposal by the ruling Saenuri Party to swiftly introduce nuclear-propelled submarines. Following a defense meeting with the government, Saenuri chief policymaker Kim Gwang-lim said North Korea’s possession of submarine-launched ballistic missiles is becoming a reality and posing a threat to South Korea’s security. Rep. Kim Gwang-lim, chief policymaker of the ruling party, told reporters after the meeting that he strongly requested the government to build a nuclear-powered attack submarine as early as possible to counter the North's SLBM threat. "The party stressed that securing a nuclear sub is an urgent task to overcome the North's asymmetric capabilities and strengthen self-defense," he said. "The government vowed to seriously consider the suggestion."

He also said that the ruling party and the government agreed on the need to speed up the establishment of the combined system of deterrence involving the Kill Chain, Korean Air and Missile Defense and the Korea Massive Punishment and Retaliation plans by the early 2020s as a way to reinforce initial response capabilities against possible North Korean provocations. Kim said that his party will push to introduce ballistic missile early warning radar systems, Taurus missiles and maritime helicopters earlier. He also pledged to try to set aside a fund during the parliamentary budget proposal process in ordered to secure more combat weapons.

With the new liberal commander in chief championing 'military self-defense' as one of his administration's core agendas, there is growing speculation South Koera could arm itself with nuclear-powered submarines. Moon brought up the issue of self-defense in April 2017 during his campaign, telling a group of reporters that Seoul is primed to have such weapons in its arsenal. During his election campaign, President Moon Jae-in said that “the time has come when we need a nuclear submarine,” adding that he would “discuss amending the South Korea-US nuclear agreement.”

On 27 August 2017, the navy announced plans to open bidding for a research project into the “legal requirements for developing nuclear-powered warships” on the government’s electronic procurement system. While the navy had initially announced on Aug. 10 that it would be taking bids for this research project, the bidding process was reportedly suspended temporarily following criticism that the scope of the research project was “too vague and broad.”

In a 20 September 2017 statement, Blue House Senior Secretary to the President for Public Relations Yoon Young-chan stated, “The reports of a South Korea-US agreement on the acquisition of nuclear-powered submarines in certain media differ from the facts,” stressing that “no agreement of any form has been reached as yet between the two sides.”

South Korea is negotiating with the United States to buy nuclear-powered submarines to guard against threats from Pyongyang, local reports said 07 November 2017, as President Donald Trump said Seoul would buy “billions of dollars” of US weapons. Nuclear-powered submarines can stay submerged for months, giving them a far greater range than their diesel-powered counterparts, and are also crucial to any seaborne nuclear deterrent. Such a purchase would redraw the balance of power in northeast Asia, and could trigger a regional arms race. “The strategic assets under discussion include a nuclear-powered submarine and a sophisticated surveillance asset,” the reports quoted a senior official of President Moon’s office as saying.

In October 2017, the ROK Navy commissioned the Seoul-based Korea Defense Network to conduct a five month study on the feasibility of developing an indigenous nuclear-powered attack submarine. The think tank reported in March 2018 the results to the Navy, suggesting the service build a nuclear attack submarine along the lines of the French 5,300-ton Barracuda-class sub. The French sub is fueled by low-enriched uranium. The use of uranium with over 20 percent enrichment for a nuclear-powered submarine could breach a 2015 nuclear agreement with the US.

A Navy spokesman said that after an assessment, the Navy will report the idea to the defense minister and then the presidential office for a final decision. However, the spokesman added that the nuclear submarine project was not to be discussed openly, considering the current mood for inter-Korean dialogue.

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Page last modified: 13-09-2021 14:44:25 ZULU