HD Hyundai and Hanwha Ocean position for $20B nuclear sub race

South Korea’s Defense Acquisition Program Administration advanced pre-tender preparations on Nov. 13, 2026, for the indigenous Jangbogo-N nuclear submarine program as rival shipbuilders positioned for basic design contracts.

The procurement agency confirmed the project framework following its Nov. 6 defense acquisition committee session. The program aims to construct nuclear-powered attack submarines through domestic research and development.

Defense officials have not published an approved budget total while formal cost-feasibility studies remain underway. Industry estimates place the multi-vessel fleet program at approximately 28 trillion won ($20.3 billion).

The timeline targets formal project initiation in 2027. Delivery milestones set the launch of the lead vessel for the mid-2030s, followed by operational deployment with the Republic of Korea Navy in the late 2030s.

The state procurement agency has not issued a formal bidding solicitation on its defense procurement portal as of Nov. 13. Official tender documentation for the basic hull design is scheduled for late 2027.

South Korea’s two primary naval yards have initiated structural reorganizations to secure the engineering lead. Hanwha Ocean and HD Hyundai Heavy Industries are competing to capture the system integration contract.

Under the procurement architecture, state defense research institutions will oversee development of the pressurized water reactor. The government will supply the reactor and primary armament modules to the winning shipyard as government-furnished equipment.

The shipyard contractor will design the submarine hull, install internal mechanical piping, and integrate reactor instrumentation with naval command systems. Coordinating hull hydrodynamics with nuclear containment structures serves as the primary technical evaluation metric.

Hanwha Ocean established an internal engineering task force titled the Jangbogo-N Development Group on Oct. 12. The unit operates directly within the shipbuilder's Special Ship Business Division at its Geoje shipyard.

Hanwha Ocean launched an external recruitment round closing late last month across five specialized operational disciplines. The hiring targeted specialists in nuclear propulsion integration, piping stress analysis, instrumentation and control, licensing regulations, and nuclear quality assurance.

Hanwha Ocean has built vessels across all three iterations of South Korea's attack submarine program. The company delivered the lead 3,000-ton KSS-III Batch-I boat and launched the second 3,600-ton Batch-II submarine in September.

Naval contracts generate over 15 percent of Hanwha Ocean's consolidated order backlog. Securing the Jangbogo-N hull contract would safeguard its submarine construction dock utilization through the late 2030s.

HD Hyundai Heavy Industries plans to challenge its rival by emphasizing commercial nuclear fabrication credentials. The shipbuilder operates naval fabrication docks in Ulsan and holds contracts for past diesel-electric KSS-II and KSS-III submarines.

Parent company HD Korea Shipbuilding and Offshore Engineering announced during its third-quarter earnings briefing that it will formalize program participation next year. The group intends to propose a joint contractor consortium model to defense authorities.

HD Hyundai executives argue that a defense build of this magnitude requires pooling nationwide naval engineering assets. The group maintains technical exposure to modular reactors through manufacturing partnerships for TerraPower sodium-cooled reactor vessels.

The group also holds basic safety approvals from international classification societies for commercial small modular reactor vessel integration. HD Hyundai aims to leverage those structural engineering data sets during procurement evaluations.

The state procurement agency confirmed that hull construction will proceed via competitive tender rather than sole-source allocation. That decision obliges both shipyards to submit independent platform architectures and pricing matrices.

Both naval shipbuilders face unresolved technical constraints regarding propulsion fuel access. South Korea's bilateral civil nuclear agreement with the United States restricts the enrichment and domestic military utilization of nuclear material.

Government acquisition documents do not clarify how the navy plans to procure low-enriched uranium fuel under 20 percent concentration. Defense authorities have not published bilateral accord amendments or formal fuel-supply protocols.

The defense procurement agency plans to establish the detailed platform system development plan in the first half of 2027. The formal request for proposals covering the submarine basic design will open in the second half of 2027.