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Silent sentinel: AI glider hunts Russian submarines in UK waters
A sleek, winged submarine glider is now patrolling the depths off Scotland's west coast, scanning for Russian vessels suspected of mapping Britain's undersea cables and pipelines. The Royal Navy is testing the SG-1 Fathom, an autonomous drone built by German defence firm Helsing, as part of a broader push to protect critical infrastructure.
How the glider works
The Fathom operates without crew, using advanced sensors to detect and identify potential threats. Its software, trained on decades of acoustic data, allows it to process and flag anomalies faster than traditional methods, according to programme manager Katie Raine.
Designed for long-duration missions, the glider can remain submerged for months, coordinating with other drones to cover vast areas. If successful, it will become a key component of Atlantic Bastion, a network combining drones, warships, and surveillance aircraft to safeguard undersea assets.
Russia's growing underwater activity
The UK Ministry of Defence announced Atlantic Bastion on Monday, framing it as a direct response to a 30% rise in Russian submarine and underwater activity near British waters over the past two years. Moscow denies provocation, accusing London of escalating tensions.
In September, the parliamentary National Security Strategy Committee warned that the UK was ill-prepared to defend its undersea cables, which carry vital financial and communications data. An attack, it cautioned, could cause "catastrophic disruption."
Last month, the Russian research vessel Yantar, suspected of mapping UK infrastructure, directed lasers at RAF aircraft monitoring its movements near British waters. Defence Secretary John Healey condemned the act as "deeply dangerous," noting the ship had repeatedly entered the UK's exclusive economic zone.
New technologies on display
During a visit to Portsmouth last week, Healey showcased several innovations aboard the Royal Navy's experimental ship, XV Patrick Blackett. Among them: a remote-controlled speedboat, a prototype of the navy's first unmanned helicopter, Proteus, and Excalibur, a 19-tonne autonomous submarine launched earlier this year.
"We know the threat Russia poses," Healey said. "They are mapping our undersea cables, networks, and pipelines, and developing new capabilities to target them. We must stay ahead."
Allies join forces as experts question UK readiness
Healey and Norwegian Defence Minister Tore O. Sandvik signed the Lunna House Agreement, a pact to jointly hunt Russian submarines and protect underwater infrastructure. "This is a rapidly evolving threat," Healey said. "It demands a rapid response."
First Sea Lord Gen Sir Gwyn Jenkins acknowledged the challenge. "Russia continues to invest hundreds of billions in its submarine fleet, despite the war in Ukraine," he said. "We're still ahead in the Atlantic, but not by as much as I'd like. We're in a competition to maintain that edge."
"The Royal Navy does not have the ships to do this job coherently or credibly and is turning to drones as a cheaper alternative to fill gaps left by decades of neglect."
Prof Peter Roberts, Royal United Services Institute
Prof Peter Roberts, a conflict expert at Rusi, called the strategy "lipstick on a pig." He argued the UK had abandoned its post-World War Two role as the Atlantic's guardian, allowing Russian activity to go "unchallenged in much of UK water space."
Russia dismissed the Lunna House Agreement as a pretext for "monitoring Russian naval activity," with Foreign Ministry spokesperson Maria Zakharova warning it could "provoke unnecessary conflicts" in international waters.
What's next
The Royal Navy will continue testing the Fathom glider and other technologies as part of Atlantic Bastion. Officials say the programme's success hinges on close collaboration with industry and allies to counter Russia's growing underwater capabilities.
