Center for Strategic Communication

The Proteus, a robotic submarine, peeks out of Florida waters during its first sea trials, Sept. 11, 2012. Its manufacturers want to convince the Navy to use it as a testbed for the fuel cells and sensors of its futuristic, long-range drone subs. Photo: Courtesy of the Columbia Group.

One of the largest unmanned submarines ever built is finally performing sea trials. But don’t expect the U.S. Navy, which dreams of undersea drones that can span oceans, to proclaim the Proteus its drone sub of the future. Instead, Proteus’ manufacturers want to work with the Navy to test the software, sensors and power systems that will define those next-gen drone subs — and maybe use the Proteus as a stopgap solution until someone develops those long-range submarines.

We first ran across the beastly Proteus at a special-operations industry conference in May 2011. It was hard to ignore: a 25-foot, 6,200 lb. black cylinder hauling two 220-lb. bomblets, with room to fit 400 lbs. of submerged cargo, or six Navy SEALs in its optional manned mode. By contrast, the SeaFox, an undersea drone the Navy is using to spot Iranian mines, is a paltry four feet long.

But the Proteus didn’t actually wade out to sea until this summer. Manufacturers Bluefin Robotics, a Battelle subsidiary, and the Columbia Group brought it to the Gulf of Mexico off of the Florida coast to put it through sea trials, shown here for the first time. The sea trials allow Proteus to work out its bugs, and already Bluefin and the Columbia group have made improvements: It can now haul up to 550 lbs. submerged. And although the longest it’s been at sea is an hour, Proteus’ various battery configurations ought to give it a range of 900 miles and a top speed of 10 knots.

That’s a big step toward the Navy’s goal of a drone sub that it can put in the water and forget about for months, while the robot collects data on the things that lurk within the briny deep. But the Columbia Group’s Ross Lindman and Battelle’s Bob Geoghegan concede they can’t engineer the Proteus to those kinds of specifications. What they can do, they say, is to offer the Proteus as a bridge technology for the things that will make the next-generation drone subs operate.

The aquatic futurists in the Office of Naval Research have a program called the Large Displacement Unmanned Underwater Vehicle (LDUUV). The idea is to build large, robotic subs that can swim out across oceans, collecting data, with enough autonomy to avoid ramming into reefs or other ships. The technical challenges something like that requires are formidable, and include designing new propulsion systems and figuring out what can power the drone sub for such a long period of time. The Office of Naval Research doesn’t expect to prepare a long-range robotic submarine this decade.

That’s where, Geoghegan and Lindman hope, the Proteus can be of use. The Navy hasn’t funded their sub. But it will need a test platform for the Office of Naval Research’s LDUUV program. “In general terms, we can provide a test bed and are providing a test bed for alternate undersea sensors; for development of intelligence, surveillance and reconnaissance packages; and we can provide the testing for different autonomies — things that would go into the LDUUV program,” says Lindman, the Columbia Group’s senior vice president for engineering. Additionally, the Navy will need to test its future power systems on an existing drone sub, and Proteus might play that role.

Beyond that, Columbia and Battelle want to talk with the Navy about purchasing Proteus as a stopgap measure until the LDUUV program bears fruit. “900 miles is a lot of open water,” says Geoghehan, Battelle’s manager of ocean engineering.

That’s probably a longer shot — at least until the Proteus has more data from its first sea trials. But they say they’re beginning to work with the Navy, as well as testing some “classified payloads” for “another DOD [Department of Defense] customer,” as Lindman puts it. Maybe the beastly sub may not just be a test platform for long.