Japan Navy deploys 10th Mogami-class frigate JS Nagara to Kure Naval Base for submarine and mine hunting.

The Japan Maritime Self-Defense Force officially commissioned the tenth Mogami-class multi-role stealth frigate, JS Nagara (FFM-10), on June 29, 2026, during a formal delivery and flag-raising ceremony at the Mitsubishi Heavy Industries shipyard in Nagasaki. This induction into the newly formed Patrol and Defense Squadron 2 at Kure Naval Base directly supports Japan's strategic shift toward a leaner, network-centric surface fleet optimized for regional deterrence and distributed maritime operations. By integrating high-level automation and a pre-installed 16-cell Mk 41 Vertical Launch System, the platform addresses critical personnel shortages while immediately delivering advanced anti-submarine, surface strike, and mine warfare capabilities.

The JS Nagara is a 5,500-ton full-load combatant displacing 3,900 tons standard, powered by a combined diesel and gas propulsion system capable of exceeding 30 knots. Built within a mature 36-month construction cycle for an estimated 52.3 billion yen, the highly automated Mogami-class vessel utilizes an Integrated Ship Handling System to reduce the required crew complement to approximately 90 personnel.

Related topic: Japan orders 3 Upgraded Mogami-class frigates to carry more missiles in Pacific operations

A single Mogami-class frigate like the JS Nagara can escort other ships, search for submarines, monitor surface traffic, and support mine countermeasures during the same deployment cycle. (Picture source: Japanese Navy)

On June 29, 2026, Mitsubishi Heavy Industries (MHI) delivered the tenth Mogami-class frigate, the JS Nagara (FFM-10), to the Japan Maritime Self-Defense Force (JMSDF) at the Nagasaki Shipyard, leaving only two ships before completion of the original 12-vessel production run. The frigate was commissioned the same day, assigned to the 2nd Patrol Unit at Kure Naval Base in Hiroshima Prefecture, and reached Kure on July 1, 2026, where it held its first arrival ceremony before starting post-commissioning training and crew qualification. The JS Nagara is also the second Mogami-class ship ordered under the FY2022 budget after the JS Natori (FFM-9), with the two-vessel procurement valued at about ¥103 billion, placing the average acquisition cost slightly above ¥51 billion per ship before broader programme, support and lifecycle costs.

Its commissioning gives the Japanese Navy ten operational Mogami-class frigates, advancing towards the replacement of the Abukuma-class destroyer escorts with smaller, lower-manning, multi-role frigates conducting escort, surveillance, anti-submarine, anti-surface and mine warfare missions. The JS Nagara followed a 36-month construction and acceptance cycle that reflects the maturity of Mitsubishi Heavy Industries' Nagasaki production line. The ship was ordered under the FY2022 defence budget, laid down on July 6, 2023, launched and named on December 19, 2024, and handed over on June 29, 2026, after outfitting, harbour work and sea trials. Its name comes from the Nagara River in central Japan, maintaining the class convention of river names.

Its hull number, FFM-10, places it after the Mogami, Kumano, Noshiro, Mikuma, Yahagi, Agano, Niyodo, Yubetsu and Natori. Mitsubishi Heavy Industries built 10 of the first 12 Mogami-class frigates at Nagasaki, giving the yard a continuous frigate construction sequence from steel work to launch, outfitting and final delivery. That continuity is important because Japan is moving directly from the initial Mogami batch to the larger Upgraded Mogami-class, reducing the risk of a production gap in a shipbuilding workforce that now has repeated experience with this class. Kure is one of the Japanese Navy's five principal naval bases and supports operations toward the Seto Inland Sea, the Bungo Channel, the Sea of Japan, the East China Sea approaches and the wider waters around western Japan.

With the JS Nagara joining the 2nd Patrol Unit, the Mogami-class now has multiple ships distributed across all major JMSDF homeports, improving availability for patrol rotations and regional response. The frigate will not move immediately into full operational tasking; it first has to complete crew certification, engineering drills, combat system validation, damage-control training, flight deck qualification and formation integration. Once that work-up is complete, the JS Nagara will contribute to maritime surveillance, escort duties, surface engagement, submarine detection, helicopter-supported anti-submarine operations and mine reconnaissance, giving the local command a ship that can shift between patrol, escort and maritime security tasks without requiring a larger destroyer or a dedicated minesweeper for every mission.

The Mogami-class's design, therefore, is built around a balance between combat capability, manpower reduction and serial affordability. The JS Nagara displaces 3,900 tonnes standard and about 5,500 tonnes at full load, with a length of 133 m, a beam of 16.3 m, a depth of 9.0 m and a draught of about 4.7 m. Its CODAG propulsion system combines one Rolls-Royce MT30 gas turbine with two MAN 12V28/33D STC diesel engines on two shafts, producing about 70,000 hp and a top speed of about 30 knots. The hull uses sloped surfaces, reduced external clutter, enclosed deck equipment and the NORA-50 integrated communications mast to reduce radar reflection, while automation allows operation with about 90 personnel.

That manning level is one of the class's most important features because older Japanese surface combatants of similar displacement commonly require 170 to 200 personnel, meaning that every Mogami-class ship can free roughly 80 to 110 sailors compared with a more traditional destroyer-sized crew model. For a navy facing demographic pressure and high patrol demand, crew reduction is not a secondary feature but a central design requirement. The JS Nagara's weapons fit gives the ship a compact but multi-layered combat package. The forward 62-calibre 127 mm Mk45 naval gun can engage surface targets and support naval gunfire missions, with conventional ammunition reaching about 24 km and compatibility with guided extended-range projectiles beyond 70 km if such munitions are introduced into Japanese service.

Close-range missile defense is provided by one SeaRAM launcher carrying 11 RIM-116 Rolling Airframe Missiles, giving the ship a final defensive layer at about 9 to 10 km against sea-skimming missiles, aircraft and helicopters. Anti-ship warfare is built around two quadruple launchers for eight Type 17 (SSM-2) missiles, generally assessed at 200 to 250 km, compared with 150 to 200 km for the Type 90 it succeeds. As the JS Nagara also belongs to the later Mogami-class configuration fitted with a 16-cell Mk41 Vertical Launch System, introduced from the JS Niyodo (FFM-7) onward, it can launch the Type 07 VL-ASROC, which reaches more than 30 km before releasing a lightweight torpedo. The ship also carries two HOS-303 triple 324 mm torpedo launchers for Type 12 or Type 97 lightweight torpedoes, generally assessed at 10 to 11 km, giving it both missile-delivered and ship-launched anti-submarine weapons.

The sensor and mission systems include the OPY-2 X-band AESA multifunction radar, which supports air and surface search, target tracking, and fire control functions, while the OAX-3 electro-optical and infrared sensor provides passive identification and tracking under conditions where radar emissions may be undesirable. The OQQ-25 variable-depth sonar and towed-array sonar improve submarine detection in waters where temperature layers and bottom conditions can complicate hull-mounted sonar performance. Link 22 connectivity and the NORA-50 integrated communications mast allow the ship to exchange tactical data with other Japanese naval units and allied forces, while the embarked SH-60K Seahawk extends the anti-submarine search area beyond the ship's own sensor horizon with dipping sonar, sonobuoys and lightweight torpedoes.

Japan has not released official detection ranges for these sensors, but the configuration indicates a ship optimized for distributed maritime surveillance, local sea control and escort operations rather than the area air defense role performed by larger Aegis destroyers. The JS Nagara's mine warfare package is also a major difference from earlier Japanese escort ships, giving the Mogami-class a role that would previously have required more specialized vessels. The frigate carries a mine-hunting sonar, one unmanned surface vehicle, one unmanned underwater vehicle, a mine disposal craft and simplified mine-laying equipment. This allows the ship to support mine reconnaissance, clearance preparation, route survey and limited mine response during patrol or escort operations.

For Japan, this matters because its naval movement depends on access through straits, port approaches, base entrances and commercial sea lanes where even a limited mine threat could slow deployment or disrupt logistics. The Mogami design does not remove the need for dedicated mine countermeasure ships, but it gives regional commanders an organic first-response capability on a combatant that can also escort convoys, track submarines and monitor surface traffic before specialized reinforcements arrive. The industrial and force-development implications extend beyond the JS Nagara.

With the JS Nagara and JS Natori procured under the FY2022 budget for about ¥103 billion, Japan has kept the first Mogami batch on a relatively stable annual production rhythm, while the JS Tatsuta and JS Yoshii remain the only undelivered ships in the initial 12-ship run. Mitsubishi Heavy Industries' Nagasaki Shipyard has built 10 of those 12 hulls and is expected to transition to the larger New FFM, which is planned to add more growth margin for air defense, strike missions and networked warfare.

The same production experience is relevant to international opportunities, particularly Australia's future frigate programme and possible New Zealand interest, because Japan can now point to an active production line, delivered ships and an operational class distributed across the Japanese Navy. For the JMSDF, once Tatsuta and Yoshii enter service, the class will provide Japan's twelve completed Mogami-class frigates before the Upgraded Mogami-class expands the same concept into a larger and more capable design for sustained distributed operations across the Western Pacific.

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.

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