Japan is in the process of building 24 new FFM (missile frigates – to be called the Mogami class). These are being procured in two batches of twelve each. Japan presently has only ten frigates. These 5,500-ton 30FFM ships are an example of successful innovation and speed in implementing new concepts. The Mogami’s take the multi-mission angle seriously. They are equipped for mine-hunting as well as mine-laying. In addition to a 127mm gun, each ship will eventually carry eight anti-ship missiles or cruise missiles in VLS cells. There are eleven SeaRAM anti-aircraft missiles with a range of ten kilometers. 16 VLS cells will carry larger Chu-SAM anti-aircraft missiles with a range of 50 kilometers as well as cruise missiles. There are twelve lightweight anti-submarine torpedoes. There is a ramp in the rear for launching and recovering UUV (Unmanned Underwater Vessels) USVs (Unmanned Surface Vessels) and RIBs (Rigid Inflatable Boats) for boarding parties. The ship also carries naval mines which it can deploy. A helicopter is also carried and that can be replaced by two or more UAVs.
The Mogami’s are stealthy, with a shape that makes it difficult to detect with radar, and carry active and passive-heat sensing sensors. There are ASW (anti-submarine warfare) and mine-hunting sonars. The active radars can also carry out jamming and other EW (Electronic Warfare) tasks. All these sensors are integrated into a single fire control system. There are two autocannon equipped RWS (Remote Weapons Stations). For passive defense there are electronic and chaff decoys to defend against incoming missiles or aircraft.
Top speed is 55 kilometers an hour and crew size is about half (at 90 personnel) what ships this size used to require. There is a lot of automation on the ship, which accounts for the relatively small crew. The Japanese automation works because, as a major civilian shipbuilder, crew automation is a key component of success in world markets. Japan pioneered many of the earliest ship automation technologies. The U.S. tried to use automation in their LCS type ship. The first of these entered service in 2008 and had so many problems that the LCS ships began retiring in 2021, before the first Mogami entered service. LCS was designed to replace the Perry class frigates, the last of the post-World War II American warship designs. The first Perry entered service in 1975 and 71 were built by 2oo4. About half the Perry’s are still in service with export customers. Admitting the LCS was a failure, the U.S. Navy selected one of several European frigate designs t0 finally replace the Perry.
The 30FFM ships were originally designed to be destroyers but, while planning equipment and weapons layout, it was realized that these ships could be multi-mission ships and the designation was changed to frigate. The 30FFMs are being built in batches, with an initial batch of eight, followed by two or three more batches, each improving on the earlier batch. The first Mogami enters service in 2024.