Conceptual rendering of the ACTUV. Image: DARPA

DARPA Is About to Start Testing an Autonomous, Submarine-Hunting Ocean Drone

The ACTUV will be able able to spend months at sea, autonomously tracking submarines from the surface.

Nov 10 2015, 4:45pm

Conceptual rendering of the ACTUV. Image: DARPA

Early next year, DARPA will begin testing a 132-foot unmanned submarine-hunting ocean drone in San Diego. Slapped with the cumbersome title of Anti-Submarine Warfare Continuous Trail Unmanned Vessel (ACTUV), it's designed to do exactly that: track stealth submarines from the surface, quietly and autonomously.

The ACTUV is currently under construction at a facility on the Oregon coast, where it is 90 percent complete. When finished, DARPA hopes it will be able to withstand months of autonomous operations at sea. It will weigh 140 tons, and will be able to hone in the quietest submarines in the water from the surface, and automatically trail them.

The vessel is so far not necessarily being touted explicitly as a weapon, but, according to DARPA, it will have the capacity to "carry a payload" and "enable independently deploying systems." On the US DoD's science site, the vessel is being compared to naval destroyers, which are currently tasked with trailing—and are outfitted to eliminate—submarines. (According to DARPA, one of the ACTUV's chief selling points is that it will be much cheaper than a naval destroyer: The drone boat costs as little as $15,000 a day to operate, versus the destroyer's $700,000 per day price tag.)


Like many of the advanced robotics projects the US military's blue sky lab is researching, DARPA seems to be leaving room to weaponize the vessel, while allowing plausible deniability as to the instrument's intent. This is especially important because the Pentagon's autonomous weapons directive prohibits fully autonomous machines from using lethal or semi-lethal force, which would apply to the ACTUV should it move beyond the testing stages and ever be outfitted with weaponry. DARPA did not respond to a request for comment.

The development also seems conspicuously timed with the re-emergence of Russia's submarine fleet, which is thought to be dispersed amongst the hotly contested Arctic—recent sightings seem to confirm their presence, and Putin has not been shy about using them in military exercises in the region.

But the focus seems to be on developing autonomous systems that can operate in water. In its official Request for Information, it states that "DARPA is interested in hardware and software solutions that enable an autonomous lookout from a surface vessel."

Meanwhile, one of DARPA's stated "three primary goals" for the initiative is to "Advance unmanned maritime system autonomy to enable independently deploying systems capable of missions spanning thousands of kilometers of range and months of endurance under a sparse remote supervisory control model," as Scott Littlefield, program manager of DARPA's Tactical Technology Office, explained in the project description.

"This includes autonomous compliance with maritime laws and conventions for safe navigation, autonomous system management for operational reliability, and autonomous interactions with an intelligent adversary," he added.

In other words, DARPA's drone boat submarine-hunter would be able to spend months at sea, where it would be able to automatically trail its target, automatically negotiate its surroundings, and, eventually, one imagines, it might automatically destroy an "intelligent adversary." The Department of Defense notes that "other advantages of the ACTUV concept include greater payload and endurance than a ship-launched unmanned surface vehicle."

The foremost objective for ACTUV is to trail submarines, but DARPA is apparently exploring other options too. "The Navy is considering using this for a variety of missions," Littlefield said in a recent announcement, according to the Department of Defense, "including mine countermeasures."

As the polar ice caps melt and sea levels rise, as new northern passageways open up for maritime trade, expect military tensions in the gas and oil rich Arctic to only ratchet upwards. Russia's belligerence has so far turned the most heads, but Canada and the US each have heavily vested interests in the region. The near future, it seems, may be marked by drones stalking submarines through the slushy detritus of the Arctic.