Sailors assigned to Submarine Development Squadron 5 prepare Large Training Vehicle 38, an unmanned undersea vehicle at Naval Undersea Warfare Center Keyport, Wash. The drone is capable of line-of-sight and over-the-horizon communications in support of intelligence, surveillance and reconnaissance missions.
The submarine development folks at Naval Undersea Warfare Center Keyport in Washington state have a new toy: an unmanned drone that can dive a half mile under the waves with battery power that lasts out to 72 hours.
The unimaginatively named but versatile UUV, called the Large Training Vehicle 38 — it’s 38 inches in diameter — is a 27-foot-long full-pressure hull built at Penn State’s test lab in 2008.
NUWC-Keyport’s UUV detachment is running through some last operational checks, with LTV-38 getting ready to hit the waves soon. It’s intended for testing and training sailors on piloting underwater drones, Submarine Force Pacific said in an Aug. 28 release.
LTV-38 is set up to gauge environmental data — things like sea temperature, depth and salinity that can have a big impact on the Navy’s underwater sensors, said Cmdr. Brook DeWalt, SUBPAC spokesman, but LTV-38 can be set up for surveillance missions as well, he said.
The 5-ton LTV-38 is about as long as a killer whale, but much slower. Max speed is four knots. Still, acquiring it is a big deal for Keyport, said Lt. Brian Nuss, officer in charge at the UUV detachment. “This is certainly a key milestone for Detachment UUV in that we will have a baseline training vehicle for the future of Large Displacement UUVs,” he said in the release.
The drone is capable of line-of-sight and over the horizon communication. It even has the ability to avoid underwater contacts through the use of acoustic sensors, which is a key feature. Among the foremost hazards of underwater drones is the risk of them colliding with vessels or platforms or getting ensnared in nets. The release makes clear, however, that its contact avoidance capabilities are limited right now.
The drone, developed for Penn State’s Sea Stalker program, was originally designed as a stealthy intelligence, surveillance and reconnaissance UUV. Sea Stalker was first launched from the destroyer Bainbridge in 2008. Sea Stalker was ultimately found useless for the fleet due to power supply problems, according to the Autonomous Undersea Vehicle Applications Center, a website that tracks industry. The Sea Stalker version was powered by d-cell batteries, the same ones that power your boom-box and your nephew’s light saber.
However, DeWalt said the impressive 72-hour power supply in the LTV-38 is due to state-of-the-art lithium-ion batteries.
Alan Beam, who headed the UUV division at the Defense Advanced Research Projects Agency in the 1990s and curates the AUVAC website, said the LTV-38’s power supply could be affected by transit time to its target area. “Seventy-two hours is ‘on-station’ time,” Beam said. “If you deploy it close to the ship then it can operate for a long time, but if it has to travel a long ways, it’s going to use up a lot of power getting out there. That will cut into the battery life.”
Beam said the LTV-38, like its Sea Stalker predecessor, could be configured to do just about anything you could want from an ISR platform — from sonar to surface surveillance — and can be equipped with advanced comms equipment to beam intel back.
In the release, Chief of Naval Operations Adm. Jon Greenert is quoted saying he envisions autonomous underwater vehicles on patrol by the end of the decade.
In May, one of the Navy’s drones was loaned to the Australian navy to search for the downed MH370 Malaysian Airlines flight.
Bluefin 21 is many times more capable than LTV-38. The 16-foot drone can dive nearly three miles beneath the water and can be used for everything from seafloor mapping and mine-hunting to ISR and anti-submarine warfare.
On the new littoral combat ships, the mine warfare package will make heavy use of drones. The Remote Minehunting System, being developed by Lockheed Martin, will have the ability to stay on station for 24 hours, looking for underwater threats and beaming back encrypted data to the mothership, keeping the LCS safely outside the minefield. It is slated to enter the service in 2017.