ROKS Dosan Ahn Changho makes first trans Pacific crossing as South Korea eyes $80 billion Canadian submarine deal.

South Korea has deployed the submarine ROKS Dosan Ahn Changho across the Pacific for the first time, arriving at Canadian Forces Base Esquimalt on May 23, 2026, after a 14,000-kilometer voyage that directly supports Seoul’s bid for Canada’s future submarine fleet. The deployment demonstrated that the KSS-III class can sustain long-range operations across Indo-Pacific and Arctic-oriented theaters while integrating with allied naval forces, a critical factor as Canada searches for up to 12 new submarines under a program valued at up to CAD 80 billion. The patrol exposed Canadian personnel to the KSS-III during real operational conditions, including Pacific transit, typhoon exposure, anti-submarine warfare drills, and combined command-system integration with Canada’s Maritime Forces Pacific.

Equipped with air-independent propulsion, lithium-ion batteries, cruise missiles, and indigenous SLBM capability, the ROKS Dosan Ahn Changho showcased South Korea’s ability to deliver operationally mature submarines already in serial production. This deployment highlights Seoul's readiness to meet Canada's urgent naval requirements as Ottawa seeks faster fleet renewal amid growing Arctic and Indo-Pacific security demands.

Related topic: South Korea deploys KSS-III submarine on 14,000 km mission as Canada's $40 Billion deal enters final phase

The deployment marked the first time a South Korean conventionally powered submarine completed a trans-Pacific crossing, and the first time a South Korean naval vessel achieved direct C4I command-system integration with Canada's Maritime Forces Pacific outside bilateral U.S. structures. (Picture source: Canadian Navy)

On May 23, 2026, the South Korean Navy submarine ROKS Dosan Ahn Changho (SS-083) arrived at Canadian Forces Base Esquimalt after completing a 14,000 km deployment from Jinhae, South Korea, through Guam and Hawaii, marking the first Pacific crossing by a South Korean submarine and the longest deployment in South Korean Navy submarine history. The mission took place during the final phase of Canada’s Canadian Patrol Submarine Project (CPSP), which seeks up to 12 conventionally powered submarines to replace the Royal Canadian Navy’s four Victoria-class boats acquired from the United Kingdom during the late 1990s.

South Korea’s bid, led by Hanwha Ocean and HD Hyundai Heavy Industries, competes directly against Germany’s TKMS Type 212CD in a program valued between $60 billion CAD and $80 billion CAD ($43.2 billion to $57.6 billion), including sustainment and lifecycle support. The Dosan Ahn Changho deployment combined operational testing, industrial positioning, NATO-oriented interoperability demonstrations, and naval diplomacy while exposing Canadian personnel directly to the KSS-III class during real operational conditions. Seoul also used the mission to demonstrate long-range deployment capability, production maturity, and alliance integration at a time when Ottawa faces declining submarine availability and increasing Arctic and Indo-Pacific operational requirements. 

The ROKS Dosan Ahn Changho departed Jinhae on March 25, 2026, transited through Guam and Hawaii, and arrived in Victoria on May 23 after nearly two months at sea under multiple Pacific operating conditions, including typhoon exposure near Guam. During the Hawaii stop, two Royal Canadian Navy submariners embarked onboard for the final operational leg to Canada, allowing direct observation of Korean submarine procedures, onboard maintenance, combat system interfaces, and crew sustainment during active deployment.

The submarine also established operational connectivity with Canada’s Maritime Forces Pacific using a combined C4I architecture, representing the first acknowledged integration between a South Korean-built submarine and Canadian Pacific naval command systems outside bilateral Korea-U.S structures. Portions of the transit were supported by the 3,100-ton Daegu-class frigate ROKS Daejeon (FFG-823), which accompanied the submarine into Esquimalt. Joint activities near Vancouver Island included anti-submarine warfare drills, operational exchanges, and command-level discussions involving South Korean Navy Chief of Naval Operations Adm. Kim Kyung-ryul and Royal Canadian Navy Commander Vice Adm. Angus Topshee.

Following Canadian operations scheduled between May 23 and June 2, the submarine is expected to continue toward Hawaii to participate in RIMPAC 2026. The KSS-III Batch-I submarine entered service in August 2021 and represents South Korea’s first domestically developed large conventionally powered submarine with indigenous vertical launch capability for cruise missiles and submarine-launched ballistic missiles (SLBMs). Depending on configuration, the submarine displaces between roughly 3,350 tons surfaced and 3,750 tons submerged while measuring between 83.5 and 89 meters in length with a crew complement of approximately 50 personnel.

Propulsion combines diesel-electric systems, lithium-ion batteries, and fuel-cell-based Air Independent Propulsion technology, allowing submerged endurance reportedly exceeding three weeks without snorkeling under favorable conditions. Armament includes six 533 mm torpedo tubes and six vertical launch cells compatible with indigenous Chonryong land-attack cruise missiles and Hyunmoo submarine-launched ballistic missiles, making South Korea one of the few non-nuclear submarine operators fielding indigenous SLBM-capable conventional submarines. The Pacific deployment tested long-duration systems' reliability, thermal management, electrical endurance, and operational continuity during extended oceanic transit under tropical humidity and severe weather conditions.

Batch-II variants currently under construction, for their part, increase submerged displacement beyond 4,000 tons while integrating expanded battery capacity and updated combat-management architecture. Canada’s CPSP requirement is driven by declining readiness within the Royal Canadian Navy’s Victoria-class fleet and by Ottawa’s requirement for sustained submarine operations across the Atlantic, Pacific, and Arctic theaters. Canada currently operates four Victoria-class submarines originally built for the Royal Navy during the 1980s, but their operational availability has remained inconsistent due to maintenance constraints, aging systems, and trained submarine personnel shortages.

Canadian naval leadership already indicated that the current force of roughly 200 submariners would need to expand toward approximately 1,000 personnel to sustain continuous operations with a future fleet of 12 submarines. South Korea’s central argument in the competition focuses on production maturity and delivery speed, emphasizing that the KSS-III is already operational and remains in serial production, unlike competing designs still moving through development or early manufacturing stages. Hanwha Ocean proposed to deliver the first submarine by 2032 and four boats before 2035 if a contract is signed during 2026, while completing the full fleet by 2043 at a pace of one submarine annually.

The Pacific crossing, therefore, functioned as a direct operational demonstration that the KSS-III can sustain trans-oceanic deployments without permanent forward logistics infrastructure while maintaining interoperability with allied naval forces. The deployment also reflected a broader shift in South Korean naval strategy toward NATO-oriented interoperability and multinational maritime integration beyond the traditional Korea-U.S alliance structure. Combined C4I integration with Canadian naval command systems demonstrated compatibility with allied operational architectures outside exclusively U.S-centered command frameworks.

Canadian submariners embarked onboard reportedly assessed compartment layouts, operational procedures, and combat system ergonomics as broadly compatible with Western submarine operating standards, reducing transition complexity for future crews. Activities near Esquimalt included anti-submarine warfare drills, operational exchanges, and discussions regarding naval cooperation and defense-industrial coordination. Participation in RIMPAC 2026 immediately after Canadian operations further linked the deployment to multinational naval activity involving Indo-Pacific and NATO-aligned maritime forces.

South Korea increasingly integrates operational military deployments into export-oriented defense campaigns, a model already visible in Korean armored vehicle, artillery, naval, and fighter jet exports tied to industrial participation agreements and government-level strategic engagement. Hanwha Ocean’s campaign extends well beyond submarine acquisition and includes industrial participation proposals centered on domestic sustainment, local manufacturing integration, and long-term Canadian involvement in submarine support activities.

Korean firms proposed maintenance, repair, and overhaul facilities on both Canadian coasts while integrating Canadian industry into sonar systems, underwater surveillance technologies, propulsion systems, combat management integration, AI-enabled simulation, naval electronics, and digital engineering. Named industrial partners include OSI Maritime Systems, Ultra Maritime, Geospectrum Technologies, Curtiss-Wright INDAL, CAE, Ontario Shipyards, Algoma Steel, AtkinsRéalis, Telesat, and MDA Space. Hanwha also proposed the establishment of the Hanwha Arctic and Defence Innovation Centre focused on AI-enabled systems, autonomy, advanced manufacturing, digital engineering, naval systems, and Arctic-related operational technologies.

Economic projections associated with the Korean proposal estimated approximately CAD 60 billion in economic activity between 2026 and 2044, alongside support for an average of 22,500 full-time jobs annually. Workforce localization initiatives additionally incorporated agreements involving Dalhousie University, Mohawk College, the University of Toronto, and the University of New Brunswick. The Canadian submarine competition forms part of a broader South Korean defense-industrial expansion strategy accelerated during the late 2010s as Seoul increasingly positioned itself as an alternative supplier capable of shorter delivery timelines than many European or American manufacturers.

South Korean exports expanded across naval systems, tanks, self-propelled artillery, missile systems, aerospace technologies, and armored vehicles through reliance on mature domestic production lines originally developed for national military requirements. Unlike several European submarine programs facing industrial bottlenecks or developmental delays, the KSS-III manufacturing continues on an active line already delivering operational submarines while Batch-II variants remain under simultaneous construction. South Korea’s shipbuilding infrastructure, centered around Geoje and Ulsan, provides one of the world’s largest concentrations of civilian and military maritime industrial capacity, enabling simultaneous naval production, sustainment, and export manufacturing.

Even if Seoul fails to secure the CPSP contract, the Pacific deployment already achieved several objectives, including the validation of long-range submarine endurance, exposure to NATO-oriented operational structures, direct integration with Canadian naval personnel, and expansion of industrial relationships within Canadian defense sectors. The deployment, therefore, represented a coordinated military-industrial influence effort tied directly to procurement competition, alliance positioning, Arctic security requirements, and South Korea’s attempt to establish a long-term strategic presence inside North American defense markets.

Written by Jérôme Brahy

Jérôme Brahy is a defense analyst and documentalist at Army Recognition. He specializes in naval modernization, aviation, drones, armored vehicles, and artillery, with a focus on strategic developments in the United States, China, Ukraine, Russia, Türkiye, and Belgium. His analyses go beyond the facts, providing context, identifying key actors, and explaining why defense news matters on a global scale.