When the Houthi rebels in Yemen first used maritime drones in January 2017, the assault on a Saudi frigate highlighted the little-known development of sea-capable semi-autonomous weapons. While maritime drone technology is not yet proliferating at the pace of aerial drones, countries like the United States, the United Kingdom, and Russia are already looking seaward in terms of drone development.
The U.S. Navy sees maritime drones as a key part of the Third Offset strategy, which seeks to leverage next-generation technologies against America’s adversaries. Unmanned Underwater Vehicles (UUVs) enable the creation of an underwater intelligence, surveillance, and reconnaissance network that mirrors U.S. aerial and land-based networks. According to a 2016 DoD report entitled “Autonomous Undersea Vehicle Requirement for 2025,” Submarine based UUVs will be used to extend the effective range of the host submarine’s sensors and weaponry. These drones will be used to carry out missions considered too dangerous for crewed vehicles, like mine countermeasures, and to serve as decoys to disguise the locations of manned submarines.
In remarks delivered aboard the USS Princeton on February 3, 2016, Defense Secretary Ash Carter said the United States would invest “$600 million over the next 5 years” in UUVs. In September 2017, Unmanned Undersea Vehicle Squadron (UUVRON) 1 was established. The U.S. Navy highlighted that “UUVRON-1 has been developing the tactics, techniques and procedures that will shape how the Navy will use the unmanned undersea vehicles.” In June 2019, the Navy reported that the Naval Undersea Warfare Center partnered with UUVRON-1 to create micro UUVs to assist with “extend[ing] the reach of the fleet; including near-shore and denied areas.” Technologists have started developing micro unmanned underwater vehicle and unmanned surface vehicle swarm technology, as well as mine-hunting UUVs for the Navy.
In April 2016, the Defense Advanced Research Projects Agency (DARPA) christened the Sea Hunter, a 132-foot autonomous ship designed to locate enemy submarines. The Sea Hunter made its first autonomous round-trip from California to Hawaii between late 2018 and early 2019.
In December 2016, the U.S. Navy demonstrated that a swarm of autonomous surface vessels could work cooperatively to patrol a harbor. The drone boats are programmed to identify and track potentially threatening vessels, both surface craft and submarines. The Echo Voyager, introduced in 2016, is a large reconnaissance UUV that can operate autonomously for six months and surface to send data to its operator via satellite. In August 2019, the Navy announced its plan to build larger, corvette-sized USVs to keep the United States competitive against other great powers.
The British Royal Navy shares the United States’ interest in maritime drones. The United States and United Kingdom staged the first Unmanned Warrior exercise in Scotland in October 2016, where drones from different countries were networked together to work as a unit.
In August 2015, Russia launched a retrofitted SSBN capable of launching crewed mini-subs as well as UUVs like the deepwater surveillance drone Klavesin-1R. In September 2015, the Washington Free Beacon reported that Russia was developing a stealthy, nuclear-armed UUV called the “Status-6”. In 2018, a leaked copy of the draft Pentagon Nuclear Posture Review confirmed Russia’s underwater nuclear weapon operability.