Mitsubishi Heavy Industries (MHI) has contracted Tokyo-based OKI to supply towed passive sonars and related equipment for the Royal Australian Navy’s general-purpose frigate fleet.
The contract, with an undisclosed value, covers equipment for the first three out of 11 improved Mogami-class stealth frigates that Australia ordered from Japan as part of a multi-billion-dollar deal signed in April.
OKI has developed underwater acoustic technologies for over 90 years and provided comprehensive support for Japan Maritime Self-Defense Forces’ sonar systems. The latest deal would mark its first overseas transfer of defense equipment.
Improved Mogami-Class
Canberra selected MHI’s improved Mogami-class frigates — designated as 06FFM — over TKMS’ MEKO A-200 frigate offer in August 2025.
The selection falls under its General Purpose Frigate program to replace the Anzac-class frigates and be deployed for escort missions, air defense roles, and attack against surface targets.
The first three will be built overseas while the remaining will be constructed in Western Australia.
The lead ship is expected for delivery by December 2029, with commissioning planned for 2030.
The improved frigates are larger than the original Mogami class, and feature 32 vertical launch cells that can launch long-range missiles.
MHI is collaborating with several suppliers to manufacture the 06FFM, including Rolls-Royce for its MT30 marine gas turbines and Raytheon for the SeaRAM Close-In Defense System.
