A volunteer team of scuba divers who regularly clean litter from the seabed say they have recovered what appears to be a Russian underwater tracking device off the coast of Pembrokeshire.
Members of Neptune’s Army of Rubbish Cleaners (NARC) found the object on 15 November during a routine dive in the Skomer Marine Conservation Zone near Wooltack Point. At first, they thought it might be part of a navigational marker, but the shape and fittings soon raised different questions. The group came to believe it resembled a sonobuoy — a floating acoustic sensor used to listen for submarines.
An independent defence analyst later examined images of the item and said he was “confident” it was an imploded Russian RGB-1A sonobuoy.
NARC chairman Dave Kennard said the device was spotted wedged in a gulley by volunteer diver Tim Smith-Gosling. After bringing it into view, the team researched the find and spoke with contacts at the Port Authority Waterway. They also compared it with similar objects reported in Cornwall and the Republic of Ireland in 2021, reinforcing their suspicion that it was military equipment.
The device, described as “battered,” is about 120cm long and weighs roughly 15kg. The divers attached a lifting bag to raise it from the seabed before guiding it to the surface. Following advice from a former Royal Navy contact, Mr Kennard reported the discovery to HM Coastguard. The Maritime and Coastguard Agency confirmed it logged the report on 19 November, adding that no one was in danger and no rescue response was needed.
Although NARC said it had never encountered anything like this before, the BBC understands such items are not uncommon around the UK given decades of naval activity in surrounding waters. A Royal Navy spokesperson declined to comment on the specific find, citing operational security, but said the service continually monitors and protects UK waters in coordination with allies.
A defence analyst and submarine specialist, who asked not to be named, said the buoy type is usually deployed by Russia’s Tu-142M long-range maritime patrol aircraft. He noted that several similar models have washed up on shores in the UK, Ireland and Lithuania in recent years. The limited marine growth on the latest device, he argued, suggests it may have entered the water relatively recently.
Strategic defence consultant Dr Andy Scollick also identified the object as a Russian hydroacoustic buoy, likely an RGB-1. He pointed to features seen on earlier examples, including three vertically aligned hydrophones and damage consistent with a deep-water implosion. He said the buoy was missing an outer sleeve that would normally be painted orange and marked with a serial number. Comparable devices have also been reported in Russia’s Novosibirsky region in 2023 and in Lithuania in 2024.
What is a sonobuoy?
A sonobuoy — short for “sonar buoy” — is an acoustic sensor designed to detect underwater activity, especially submarines. Because radio and GPS signals don’t travel well through seawater, these devices play a key role in modern naval surveillance and are commonly used during exercises and operations.
First developed in World War Two to track German U-boats, sonobuoys became central to Cold War anti-submarine missions and remain standard tools today. They have also been used in major search operations, including the 2023 hunt for the Titan submersible and efforts to locate Malaysia Airlines Flight 370 in 2014.
Authorities warn that members of the public should never touch or attempt to move suspected sonobuoys, as they may contain hazardous materials. Anyone who finds one should call 999 and ask for the coastguard.
The discovery comes in the same week the UK Defence Secretary, John Healey, confirmed that the Russian vessel Yantar had been operating near the edge of UK waters. Russia describes the ship as an oceanic research vessel, but Western governments have long tracked its movements amid concerns it could be surveying undersea cables that carry more than 90% of the UK’s data, including high-value financial traffic.
In a recent escalation, reports claimed RAF patrol aircraft were targeted with lasers from the ship — an act Mr Healey described as “deeply dangerous.” He said the UK was prepared to respond if the vessel moved further south. The Russian Embassy said in a statement that Russia was “not interested in British underwater communications.”
