A new module will outfit the Navy’s Virginia-class submarines with a series of useful tubes waiting to be filled with possibility. New missiles and possibly torpedoes will likely form the bulk of new payloads for the Virginia Payload Module (VPM), but one of the possibilities is as an exit point for vertically berthed underwater uncrewed vehicles, a home and launching point for robots waiting to scout the surrounding sea.

Upgrading firepower is the adaptation that initiated the program, which will meet needs as the Navy looks ahead to the threats of the middle part of the 21st century and possible advancements in naval warfare by other great powers such as Russia and China. However, as the Virginia-class submarines near the culmination of their second decade in service, the ability to add more robots to the mix is just a modification and a new battery away.

“We are working, obviously right now, on abilities like torpedo tube launch and recover for UUV,” said George Drakeley, executive director for the Program Executive Office for Submarines.

“We already had the ability to launch, recover from drydock shelters and, you know, in the Virginia bloc upgrades we are working options to make sure that we can bring UUVs in this theater.”

But robots, too, will be part of this new seascape, and not just the protagonists of techno-thriller fiction like P.W. Singer and August Cole’s “Ghost Fleet.” We got a glimpse into the why and what of those robots Nov. 7 during the Naval Submarine League symposium.

“I know there’s always frustration on how quickly UAVs have made their way through the day-to-day life of the war fighter. I will tell you that unmanned undersea vehicles are more challenging from the perspective,” said Drakeley.

“They are truly autonomous. There’s no guy manning the joystick. There’s no lawyer standing behind the guy manning the joystick. So we have to make some serious technology into those unmanned vehicles to make sure that they’re capable of doing what we want. More importantly, we have to make sure that we can charge those vehicles. And, most importantly, we have to be able to get the data off those vehicles and make sure that they’re tactically relevant.”

While airborne remotely piloted craft have captured the image of modern uncrewed warfare, remote signals below the surface have always been a trickier proposition. The medium of air is permissive to signals; water, meanwhile, is inherently hostile. Yet the trend in uncrewed vehicles on land air and sea is toward autonomy, as the electromagnetic spectrum moves from a permissive to a contested to a denied domain. Underwater vessels, especially untethered machines, are already operating in that space as intelligence, reconnaissance and surveillance platforms.

“We look for capabilities that can help the synergy with unmanned undersea vehicles and will also give us the ability to move forward in the realm of seabed and sub-sea warfare,” said Drakeley.

Making any of this possible will be new power supply and, possibly, new VPM-shaped robots. Batteries that can transition from vertical to horizontal orientation smoothly, like lithium ion batteries, are essential to making the tubes work as launching points for new robots. Should that hurdle be passed, and the design challenges of handling a new robot into a tube also tackled, there’s a vast space of possibilities for what the robots could do and how they could enhance the existing missions of the submarines.

Already, there are UUVs that can launch airborne drones. A submarine that could house robots that can launch more robots could become the central node in covering a huge swath of sea with sensors or other payloads. The submarine could seed the sea with smaller robots, and maybe release a robotic maintainer that manages already existing underwater swarms. As robotic swarms of surface ships patrol contested areas, a robot release from a submarine could counteract that force multiplication. Loitering munitions, which already exist in airborne form, could become a feature of underwater warfare, as submarine-launched torpedo-sized robots search for hostile signals and turn deadly in response to the right triggers.

There are developments that need to happen to bridge the gap between that future and the speculation of the now, but already the world of underwater machines looks stranger than expected. The future is likely both more robotic and stranger still.

Defense News Naval Warfare Reporter David Larter contributed to this story.

Kelsey Atherton blogs about military technology for C4ISRNET, Fifth Domain, Defense News, and Military Times. He previously wrote for Popular Science, and also created, solicited, and edited content for a group blog on political science fiction and international security.

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