Mogami-class frigate

The Mogami-class frigate (もがみ型護衛艦), also known as 30FFM, 30FF, 30DX, or 30DEX, is a Japanese multi-mission stealth frigate for the Japan Maritime Self-Defense Force (JMSDF).

Development
In 2015, the Japanese defense budget allocated funds to study the construction of a new "compact-type hull destroyer with additional multi-functional capabilities", as well as a new radar system for the destroyer. In 2015, Mitsubishi Heavy Industries (MHI) unveiled the frigate's first concept model (30FF) which they had been developing with their own funds.

In August 2017, the Acquisition, Technology & Logistics Agency (ATLA) selected MHI and Mitsui Engineering and Shipbuilding as the prime contractor and subcontractor to construct the frigate. The agency selected a completely new design of the vessel (30DX). The new ship is set to replace the Asagiri-class destroyers and Abukuma-class destroyer escorts.

Construction of the 30DX was to begin in 2018. A total of twenty-two units built to this design are planned by 2032. The first eight were under contract by 2018. A pair are to be built each year.

In January 2023, ATLA announced the "Guidelines for Recruiting Applicants for the 'Plan Proposal Contract for the New FFM'". The new FFM based on this is scheduled to start construction from the FY Reiwa 6 plan, and as a result, the construction of the Mogami type will be completed with 12 ships up to FY Reiwa 5 plan ship.

In March 2024, it is reported that Mogami-class frigates will be equipped with VLS systems in FY 2024.

Design
The overall intent of the 30DX design is to achieve a modern frigate-sized vessel with capabilities similar to the Akizuki-class destroyer but with a reduced crew and having only half the VLS cells.

30FF
The original intention was to use the 30FF model. The 30FF design looked similar to the United States Navy's Freedom-class littoral combat ship with an integrated mast. Its armament included a 5"/54 caliber Mark 45 gun, two remote weapon stations between the bridge and main gun, a SeaRAM battery above the helicopter hangar, and an onboard helicopter. The length of this version of the vessel was to be 120 m, with a max beam of 18 m, and a displacement of about 3000 MT. The 30FF design had a planned maximum speed of 40 kn and accommodated a crew of about 100.

30DX
The 30DX model was eventually chosen to be constructed. The 30DX design, although modern, is more conservative compared to the 30FF's more radical approach. The three main factors for the design change were due to the need for affordability, miniaturization/automation, and multi-mission capabilities. The vessel has a length of 130 m, a breadth of 16 m, a standard displacement of 3900 MT with a full load displacement of about 5500 MT. It has a maximum speed of over 30 kn. The frigates will be powered by a Rolls-Royce MT30 gas turbine.

Weapons for the 30DX include a Mk 45 gun, two remote weapon stations above the bridge, a 16-cell Mk 41 Vertical Launching System (VLS) at the bow, 8 anti-ship missiles, one SeaRAM, an SH-60L helicopter, torpedoes, and decoy launchers. Another capability is to deploy and recover unmanned underwater vehicles (UUV), unmanned surface vehicles (USV), and sea mines from the rear ramp beneath the helo deck. The 30DX is expected to use a naval version of the JGSDF's Type 03 Chū-SAM long-range AA missile.

The stealthy design of both models is based on the research and development lessons learned from the Mitsubishi X-2 Shinshin, then: ATD-X, stealth fighter technology demonstrator, as both platforms are designed by Mitsubishi Heavy Industries. Along with stealth capabilities, the frigate emphasizes a high level of automation. This allows the frigate to possess a small crew size of only 90 personnel when compared to the crew complement of other ships of similar size.

Automation
At Sea Air Space 2019, Mitsubishi Heavy Industries revealed their 'Advanced Integrated CIC' for the vessel. It will combine the wheelhouse, the managing and situational awareness room, the engine and power control room, and combat information center within a large 360-degree circular screen wall. It can display panoramic views around the ship without a blind spot on the screen, and will utilize augmented reality technology to discriminate among the objects shown and to navigate the ship.

Operational concept
On 16 December 2022, the Japanese Ministry of Defense released its Defense Buildup Program (防衛力整備計画) guidance, which noted that the Japanese Maritime Self Defense Force plans to replace its fleet of older, less capable destroyers and Abukuma-class destroyer escorts with Mogami-class frigates.

Ships in the class
Niyodo (FFM-7) and subsequent ships will be equipped with a Vertical Launch System. Ships from FFM-1 to FFM-6 are commissioned without VLS and will be later equipped with VLS. {{legend|#ADE2B8|Planned date}}

Export
Both frigate designs have been showcased in four naval exhibitions to attract potential export customers. The 30FF was shown in PACIFIC 2015 as a contender for the Royal Australian Navy's SEA5000 ASW Frigate Program and on display again at Sea Air Space 2017. The 30DX design was shown in Sea Air Space 2018, as well as 2019, and Euronaval 2018. The new FFM design was showcased at Indo Pacific 2023 as the 'FMF-AAW'.

Australia
The FFM design was shortlisted as a contender for the Royal Australian Navy's new general purpose frigates. Australia plans to acquire eleven frigates. The first batch of ships will be built overseas before transitioning to an Australian build.

The Mogami is competing with Germany's MEKO A-200, South Korea’s FFX Batch II/III, and Spain’s Alfa 3000 as proposed entries for RAN's next frigate.

Indonesia
Japan plans to export four frigates to Indonesia either on late 2023 or early 2024. Another four will be built in Indonesia under a ¥300 billion contract under PT PAL. In March 2021, Japan and Indonesia signed a military cooperation agreement, which reinforces the delivery.