REMUS 300

The REMUS 300 is a small-class, two-person portable unmanned underwater vehicle (UUV) designed for military and commercial applications. Manufactured by Hydroid, a subsidiary of Huntington Ingalls Industries (HII), the system entered commercial availability in April 2021 after HII acquired Hydroid from Kongsberg for $350 million in March 2020. The vehicle is primarily utilized for mine countermeasures, search and recovery, anti-submarine warfare (ASW), and intelligence, surveillance, and reconnaissance (ISR) operations. It is also employed for hydrographic survey and rapid environmental assessment.

Built on the REMUS Technology Platform, the REMUS 300 features a 7.5-inch-diameter hull configuration derived from the earlier REMUS 100 UUV. The system is rated for depths up to 305 meters and offers an estimated endurance of up to 30 hours. Its design emphasizes modularity and payload flexibility, allowing for the rapid integration of various wet or dry payloads. This open-architecture approach enables operators to tailor the vehicle for diverse missions, ranging from defense operations to marine archaeology and offshore oil and gas support. The vehicle is powered by Odyssey, a cross-domain asset management suite that facilitates collaborative autonomy across missions and platforms, enhancing operational efficiency and control.

The United States is a primary operator of the REMUS 300, alongside other nations. Hydroid has sold more than 500 REMUS UUVs to 25 countries. In July 2025, HII received an order from Hitachi for more than a dozen REMUS 300 vehicles under a multi-year delivery programme. The system is not combat-tested in active conflict zones but is fielded for defensive and surveillance roles. It competes in the mid-range AUV market, bridging the gap between coastal and deep-shelf operations with increased payload flexibility over the REMUS 100. The REMUS 300 represents a significant evolution in underwater robotics, offering advanced capabilities and interoperability while reducing cost and risk for operators.