Britain’s Rolls-Royce revealed plans to offer a a large autonomous naval vessel for single-role missions on Tuesday.

Unlike small drones or unmanned undersea submersibles, the company described the vessel as being able to operate over-the-horizon for over 100 days, reach speeds over 25 knots, and conduct various single-role missions like patrol and surveillance, mine detection, and fleet screening,

A Rolls-Royce concept for an autonomous naval vessel deploying drones. (Artists’ concept: Rolls-Royce.)
A Rolls-Royce concept for an autonomous naval vessel deploying drones. (Artists’ concept: Rolls-Royce.)

The 60-meter long vessel will displace 700 metric tons, have a range of 3,500 nautical miles, and feature a full electric propulsion system, the company said. That includes two Rolls-Royce MTU 4000 Series gensets to provide 4 megawatts (MW) of electrical power to a 1.5 MW propulsion drive. This electric propulsion would require fewer auxiliary systems like lubrication and cooling as well as better reliability compared to mechanical system, Rolls-Royce said.

The company said an alternative to more standard diesel ship engines could be small gas turbines, which improve the system’s reliability and reduce maintenance.

Benjamin Thorp, Rolls -Royce’s general manager for Naval Electrics, Automation and Control, highlighted in the announcement that “Rolls-Royce is seeing interest from major navies in autonomous, rather than remote controlled, ships.”

Autonomous ships can deliver an increased operational capability while reducing crew risk, operating costs, and building costs, he added.

Thorp said the company expects to lead the field and that “over the next 10 years or so, Rolls-Royce expects to see the introduction of medium sized unmanned platforms, particularly in leading navies, as the concept of mixed manned and unmanned fleets develops,” Thorp said.

The company underscored the “heart” of this concept is the power dense propulsion system that combines Rolls-Royce’s experience in gas turbines, diesel propulsion, and “a demonstrable track record in electric propulsion, energy storage and propulsors.”

Rolls-Royce’ vision sees larger manned ships conducting multi-role missions while smaller autonomous ships conduct limited single role missions. This allows navies to “reap the operational and cost benefits offered by autonomous technology,” the company said.

Other features of the ship design include Permanent Magnet Azipull thrusters and a bow-mounted tunnel thruster to make the ship very maneuverable; additional 3,000 kilowatt hours (kWh) of energy storage to facilitate efficient low-speed loiter operations to reduce fuel consumption and extend operational range; and the use of photovoltaic solar panels to generate power when the ship is on standby.

The company intends to combine advanced Intelligent Asset Management and system redundancy in a way that avoids sacrificing cost and volume savings attained by removing a crew. The ship will also include a suite of autonomous management and monitoring support tools developed by the company to ensure ship availability.

“Many of the technologies needed to make autonomous ships a reality already exist,” the company said.

Rolls-Royce is also conducting significant analysis” of possible cyber risks to such systems to ensure end-to-end security.

The company did not reveal when such a vessel may be ready to offer or what specific countries it is targeting for contracts by publication time.