HII Announces Hitachi Order for REMUS 300 SUUVs

HII announced an order from Hitachi, Ltd. for more than a dozen REMUS 300 small uncrewed undersea vehicles (SUUVs) under a program that will deliver the vehicles over multi-years.

HII’s REMUS 300 platform is a modular, open-architecture SUUV engineered for multi-mission adaptability and was the commercial basis for the U.S. Navy’s Lionfish program.

The procurement by Hitachi builds on a long-standing relationship with Japan, an important U.S. ally in the Pacific region. The REMUS 300 platform is in service with several nations worldwide and offers critical interoperability with partner and allied forces.

The REMUS UUV family delivers critical advantages across modern naval operations and the autonomous systems have been proven to operate independently or in conjunction with crewed platforms—such as Virginia-class nuclear submarines—to extend mission range, reduce detection risk and limit personnel exposure.

The REMUS open-architecture design allows rapid payload integration, enabling mission-specific configurations and future tech insertions—key factors in maintaining operational relevance and cost efficiency over time.

To date, HII has sold more than 700 REMUS vehicles to over 30 countries, including 14 NATO members. Notably, over 90% of REMUS units delivered in the past 23 years remain in service, demonstrating platform durability and lifecycle value—both critical in defense acquisition decision-making.