South Korea Outsources Warship Maintenance for the First Time: Hanwha Ocean to Overhaul ROKS Sejong the Great

The Republic of Korea Navy (ROKN) has awarded Hanwha Ocean a contract to carry out a full depot-level overhaul of the 7,600-ton KDX-III Aegis destroyer ROKS Sejong the Great (DDG-991). Signed on August 27, the deal marks the first time Seoul has outsourced comprehensive maintenance of a surface combatant entirely to the private sector.

At a Glance

• Contract signed with Hanwha Ocean on August 27, 2026.
• Ship under overhaul: ROKS Sejong the Great (DDG-991), lead vessel of the KDX-III Aegis destroyer class.
• Work is expected to begin in September 2026 and run roughly six months, through March 2027.
• It is the ROK Navy’s first fully outsourced depot-level maintenance, repair and overhaul (MRO) for a surface combatant.
• The navy plans to progressively expand the model through the 2030s, aiming for fleet-wide implementation by 2040.

Background

The Sejong the Great class represents South Korea’s largest and most capable surface combatants, built around the Aegis combat system and tasked with everything from air defense to ballistic missile defense duties. Until now, deep maintenance work on these destroyers has largely stayed in-house, run through the navy’s own shipyard resources and personnel.

Under the new contract, Hanwha Ocean will handle the roughly six-month overhaul using its own infrastructure, specialized workforce and technical expertise. The ROKN’s stated rationale is straightforward: freeing crews from maintenance duties lets sailors spend more time on combat training and operational readiness. Navy officials have signaled that, if the integrated MRO model proves successful, it will gradually extend to other surface ships through the 2030s, with the ambition of becoming the fleet-wide standard by 2040.

Hanwha Ocean has been steadily building out its maintenance and repair portfolio in recent years, both for the South Korean navy and for foreign customers — the company previously completed a large-scale maintenance job on a U.S. Navy support ship. The Sejong the Great contract fits into a broader strategy of positioning the shipyard not just as a newbuild powerhouse but as a regional hub for fleet sustainment.

Regional Impact

South Korea’s move reflects a wider trend among navies with limited crew pools: shifting deep maintenance to capable private shipyards so warship crews can concentrate on training and operations rather than upkeep. It also sharpens Hanwha Ocean’s competitive position in a global MRO market where South Korean, European and Turkish shipyards increasingly compete for the same contracts — from newbuild exports to long-term sustainment deals. As navies across Asia and the Gulf modernize destroyer and frigate fleets, the MRO track record a shipyard builds at home often becomes a selling point in export competitions abroad.

FAQ

What class of ship is ROKS Sejong the Great?
It is the lead ship of the KDX-III class, a 7,600-ton Aegis-equipped guided-missile destroyer — the largest surface combatant class in the South Korean navy.

Why is this contract a first?
Because deep, depot-level maintenance on ships of this size had previously been handled mainly through the navy’s own resources; this is the first time the work has gone entirely to a private shipyard, Hanwha Ocean.

When will the overhaul be finished?
Work is expected to start in September 2026 and take about six months, wrapping up in the first quarter of 2027.

Sources

• Naval News, “Hanwha Ocean to Conduct ROK Navy’s First Outsourced Destroyer Overhaul”
• The Defense Post (DefPost), announcement of the ROK Navy–Hanwha Ocean contract