19 July 2017
Run silent, run deep — and now, run in packs? Submarines are traditionally lone wolves, but the rise of robotics is starting to change that. Just yesterday, defense contractor BAE announced a $4.6 million award from DARPA to build an Unmanned Underwater Vehicle (UUV) to accompany manned submarines, helping them spot targets by sending out active sonar pulses.
While the contract is tiny by Pentagon standards, it’s a harbinger of things to come underwater. Done right, the sonar drone could give bubbleheads a new advantage at a time when Russia and China are copying our old ones. But there are plenty of technical and tactical hurdles to overcome. The first is cramming a sufficiently high-powered sonar, an underwater datalink, and an adequate power source in a drone small enough to launch from a torpedo tube. If you can do all that, then you have to make sure the sonar and datalink aren’t too powerful, or they’ll give away the drone’s location — or even help the enemy find the manned submarine itself.
Known as MOCCA (Mobile Offboard Clandestine Communications & Approach), the sonar UUV would help the manned mothership detect enemy submarines at greater distances, without being detected in return. Active sonar, which sends out a pulse of sound — that loud “PING” you hear in war movies — has a much longer range than passive sonar, which merely listens. But submarines generally rely on passive sensors, because the enemy can home in on active pulses. If the sub can launch an unmanned underwater vehicle with active sonar, though, the UUV can move a safe distance away before it starts pinging. Yes, the enemy may well detect the drone, but even if they destroy it, the manned sub is safe.