VESSEL REVIEW | Stormrunner – Compact USV for logistics, surveillance and counter-drone missions

Boston, Massachusetts-based unmanned systems manufacturer Sea Machines Robotics has introduced a new type of autonomous unmanned surface vehicle (USV) optimised for a range of commercial and security applications.

Designed from the keel up for autonomous operation, Stormrunner is powered by Sea Machines’ autonomous command and control system, which has also been fitted on a number of commercial vessels.

The USV has a monohull design, a length of eight metres (26 feet), a beam of 2.35 metres (7.71 feet), and a large, watertight electronics bay. The compact size will permit transport inside a 40-foot ISO container.

A Cox Marine CXO300 300hp (220kW) diesel outboard engine delivers a top speed of more than 40 knots, a cruising speed of 27 knots and a range of over 700 nautical miles. Although the first example is powered by an outboard, the USV offers the option to be fitted with an inboard engine with sterndrive. Either configuration can deliver 40-knot sprint speeds and efficient cruise profiles suited for long-range autonomous missions.

Long-endurance, low-observable platform

“Stormrunner is powered by our autonomy system, which enables over-the-horizon control, dynamic mission editing, and collision and obstacle avoidance,” Sea Machines told Baird Maritime. “The vessel was designed and built to be a highly reliable, long-range and long-endurance autonomous maritime platform that is attritable.”

Constructed from HDPE, the USV is highly rigid and resistant to weather-related corrosion. Combined with the diesel propulsion system, the craft is well-suited for long-duration and long-distance missions including logistics, hydrographic survey, electronic warfare (EW), and intelligence, surveillance and reconnaissance (ISR).

The USV was developed to provide an ideal balance between cost and value, offering military-grade capability at commercial pricing levels.

“The requirement was for a vessel capable of adapting to a wide range of mission profiles without redesign,” the builder added. “That includes long-range operations with integrated payloads, such as counter-unmanned aerial systems (counter-UAS) radars, from a fully autonomous uncrewed surface vessel. The platform also needed to support a modular payload bay for large, mission-specific equipment while maintaining high endurance and persistent autonomous operation.”

The USV was built for coastal and open-ocean employment and conducting long-endurance missions in contested or denied environments.

“We offer this line of USVs to move the market and help create exposure. Inherently, USVs allow operators to shift risk from human to machine, so it is possible to increase levels of calculated risk to optimise for mission effectiveness."

Sea Machines added that Stormrunner delivers persistent ISR and logistics capability without putting personnel at risk, cutting mission costs and freeing crewed assets for higher-value tasks. The result is expanded operational reach and increased operational tempo. It can also host advanced payloads, including counter-UAS radars, on a fully autonomous maritime platform when required.

Technology company Leonardo DRS has even selected the USV to demonstrate its maritime mission equipment package for counter-UAS missions. In Sea Machines’ view, the selection emphasises the USV’s role as a practical autonomous platform for carrying advanced mission systems forward into the maritime environment, giving commanders a way to extend detection, tracking and response capability without placing sailors or high-value maritime assets at unnecessary risk.

“Operating counter-UAS equipment from a fully autonomous maritime platform is an emerging capability, and Stormrunner provides a practical way to advance and refine it with partners while expanding the range of missions that can be conducted without crewed exposure,” Sea Machines told Baird Maritime.

Full standard electronics suite plus customisable sensor payload

The communications suite includes Starlink, 4G LTE, Iridium and discrete radio options for over-the-horizon command and control, with failover hardware. The USV’s electronics setup is fully integrated to support vessel control, autonomous functions and payload operation, with dedicated 12V and 24V power distribution for systems with different load requirements.

“The notable element is the resilience designed into the architecture: it maintains safe autonomous behaviour in degraded environments through comms-loss hardening and loss-of-position safeguards.”

The other electronics include a radar, a GNSS receiver, a VHF radio/hailer, a class B AIS, and RGB and thermal cameras. PTZ cameras may be optionally fitted for ISR missions.

The enclosed payload bay can support up to 1,000 lb (450 kg) of mission equipment, enabling modular role changes across missions such as ISR, EW and logistics.

Built for resilience as well as performance

For Sea Machines, balancing stability, speed and efficiency while incorporating HDPE’s material advantages into a high-performance autonomous platform proved the main challenge in the design work on the USV.

“Unmanned vessels experience operating loads that are fundamentally different from crewed craft,” the builder added. “There is no human onboard sensing when conditions warrant slowing down.

Sea Machines therefore spent significant time ensuring the hull structure and sensor mounting were engineered and built to withstand repeated use under Sea State four conditions. The company said this deliberate engineering approach, combined with the choice of working with ultra-durable HDPE material, provides the ability to exceed the performance requirements expected of traditionally constructed vessels.

“We listened to the needs of our customers and made changes for future payload integrations,” Sea Machines told Baird Maritime. “A major recent requirement has been the ability to integrate C-UAS capabilities [as explained above.