Divers from Neptune’s Army of Rubbish Cleaners (NARC) weren’t expecting geopolitics on their routine 15 November debris sweep in the Skomer Marine Conservation Zone off Pembrokeshire. But that’s what they got.
What first looked like a scrap of navigational equipment quickly raised eyebrows. The team realised the barnacle-scarred tube resembled a sonobuoy — the kind of acoustic sensor militaries use to listen for submarines.
Their hunch was right. An independent defence analyst said he was “confident” the object was the imploded remains of a Russian RGB-1A sonobuoy.
NARC chair Dave Kennard said volunteer diver Tim Smith-Gosling found the device wedged in a seabed gulley. After consulting the Port Authority Waterway and comparing notes with earlier finds in Cornwall and Ireland, the group concluded the battered 120-cm, 15-kg cylinder matched known Russian models.
Kennard followed Royal Navy advice and reported the discovery to HM Coastguard. The Maritime and Coastguard Agency logged the case on 19 November but said no safety response was needed.
For NARC — a volunteer outfit better known for hauling fishing line and discarded gear from Welsh waters — the find was a first. But defence sources told the BBC such devices aren’t unusual given decades of submarine-hunting around the U.K.
The Royal Navy declined to comment on the specific discovery, citing operational security, but said it maintains continuous surveillance of U.K. waters with allied support.
A second defence analyst, who requested anonymity, also identified the device as a Russian RGB-1A buoy, typically dropped by Russia’s Tu-142M long-range patrol aircraft. Several of the same type have washed up recently in the U.K., Ireland and Lithuania, he noted — and the limited marine growth suggests this one was “likely dropped recently.”
Strategic defence consultant Dr. Andy Scollick reached the same conclusion, pointing to distinctive features such as three vertically stacked hydrophones and signs of deep-water implosion. The buoy’s orange serial-numbered sleeve was missing.
Similar devices have surfaced in Russia’s Novosibirsky region in 2023 and Lithuania in 2024.
Sonobuoys — a blend of “sonar” and “buoy” — are essential tools for tracking underwater activity, first deployed in World War II and still central to modern anti-submarine warfare. They remain classified as hazardous; authorities warn the public not to handle them and to call 999 instead.
The timing of the discovery is notable. It comes the same week Defence Secretary John Healey confirmed that Yantar — a Russian vessel Western officials suspect of surveying critical undersea cables — had been operating near the edge of U.K. waters.
Those cables carry more than 90 percent of Britain’s data, including billions in financial transactions. And the find on the Welsh seabed is an unwelcome reminder: the undersea chess match between Russia and the West is alive and well — and happening much closer to home than many realise.