In a move that reflects the deep-rooted defense ties between Japan and the United States, Tokyo-headquartered Hitachi has approached Huntington Ingalls Industries (HII) with a request to supply over a dozen REMUS 300 small uncrewed undersea vehicles (SUUVs). The agreement spans several years, although it remains unclear whether the purchase is intended for the Japan Maritime Self-Defense Force.
The REMUS 300, which has also been adopted by the U.S. Navy under its Lionfish initiative, stands out for its customizable modular design, allowing operators to swiftly integrate new payloads and reconfigure the vehicle based on evolving mission needs. This adaptability ensures that the platform remains upgradeable and mission-ready across a range of operational scenarios.
The vehicle runs on a 4.5-kWh lithium-ion battery, enabling underwater operations for up to 30 hours at depths of 305 meters (1,001 feet). It can travel at a top speed of 5 knots (9 km/h or 6 mph) and cover 165 kilometers (102 miles) on a single charge. Two alternative battery configurations—1.5 kWh and 3.0 kWh—are available, though they come with decreased endurance and operational capacity.
At just over 2 meters (6.66 feet) in length, the REMUS 300 is compact yet versatile. Its ability to work in tandem with crewed systems like submarines enhances mission flexibility, offering expanded operational range and lower chances of enemy detection.
