Drones have revolutionized modern warfare in the sky. Now defense companies and navies are betting they can do the same underwater.
The new underwater drones, with names such as Ghost Shark, Herne and Manta Ray, can typically dive thousands of feet below the surface and operate largely without human interaction for days on end. That ability makes them ideally suited to gather intelligence, protect undersea infrastructure and counter potential threats in the Pacific, advocates say.
