Romulus USV Passes Critical Military Test
HII has announced that the U.S. Defense Innovation Unit (DIU) has officially recognized the successful completion of the company’s production-ready, inexpensive, maritime expeditionary (PRIME) prototype project.
The prototype features the Watcher small unmanned surface vessel (sUSV), which is based on HII’s Romulus-25 USV and powered by HII’s Odyssey autonomous control system.
The DIU recognition follows HII’s delivery and successful sea testing of two autonomous Watcher Romulus-25 vessels in December 2025 under a DIU contract to develop smaller-form-factor autonomous surface vessels for the U.S. Marine Corps.
The two Romulus-25 autonomous vessels completed extensive at-sea testing, successfully demonstrating advanced autonomous mission behaviors across a range of operational scenarios, including contractor demonstrations, government-led autonomy assessments, seakeeping and performance evaluations, and degraded-environment testing.
Developed in partnership with MetalCraft Marine, the Watcher sUSV successfully met the program’s technical objectives and is now positioned for a potential transition to production.
HII’s Odyssey autonomous control system modular open systems architecture enables intelligent navigation, mission planning, collaborative behaviors, and multi-domain autonomous operations while allowing operators to rapidly integrate autonomy across multiple vehicle types and increasingly complex missions in contested environments.
Its service-based design enables seamless integration with other mission-enabling technologies, enhancing mission effectiveness through AI-enabled contact recognition, identification, and edge-based decision-making.
In a memorandum to HII, DIU stated: "The HII Watcher sUSV has successfully demonstrated its appropriateness to address the Department of the Navy’s operational need for sUSV interceptors, capable of autonomously transiting hundreds of miles through contested waterspace, loitering in an assigned operating area while monitoring for maritime surface threats, and then sprinting to interdict a noncooperative, maneuvering vessel."
The memorandum further concluded that HII achieved the prototype’s key technical goals and success metrics, supporting a potential transition to production under Other Transaction Authority prototype agreements.
The PRIME initiative challenged industry to deliver commercially available, production-ready autonomous surface vessels capable of supporting maritime expeditionary operations. Following a full and open competition that attracted 116 solution briefs, HII was selected to design, build, and demonstrate its solution.
The Romulus-25, part of HII’s expanding family of autonomous unmanned surface vessels, is a high-speed interceptor capable of carrying payloads of up to 1,000 pounds and operating at ranges of up to 1,000 nautical miles.