An account by a Royal Navy submariner who has blown the whistle on poor safety standards in the Trident nuclear weapons programme has provided new information about an underwater collision involving two nuclear armed submarines.
William McNeilly, who has published an online account exposing equipment failures, crew errors, and lax standards on board HMS Vanguard, gives a second-hand account of an incident in February 2009 when HMS Vanguard collided underwater with the French ballistic missile submarine FNS Le Triomphant. The incident remains highly sensitive in defence circles and little has been said publicly about it by official sources. Following the accident, the then defence minister Bob Ainsworth said that he would withhold “all particulars” of the collision from release on grounds of national security.
McNeilly's account suggests that the incident was far more serious than was acknowledged by the Ministry of Defence (MoD) at the time. He states that whilst serving on board HMS Vanguard he spoke to a Chief Petty Officer who had been on board the submarine at the time of the accident. “He said “We thought, this it we're all going to die””.
During the collision rhe French submarine had taken a “massive chunk” out of the front of HMS Vanguard and had then grazed down the side of the boat. Compressed air bottle groups had been dislodged by the collision and “were hanging off and banging against the pressure hull”. The submarine had to return to base slowly because “if one of HPA [high pressure air] bottle groups exploded it would've created a chain reaction and sent the submarine plummeting to the bottom”.
On returning to Faslane “there was a massive cover-up of the incident”. McNeilly's informant said “they told him if he told anybody about it he'd faced a prison sentence”. MoD statements and media coverage of the incident made no mention of the explosion risk or the submarine's perilous journey back to base.
McNeilly's version of events shines some light on why the submarine took an extended ten day period to return to Faslane from the Bay of Biscay after the collision, and probably also explains why Commander Richard Lindsey, the submarine's captain during the incident, was subsequently awarded the Queen's Commendation for Valuable Service for “courage and high quality leadership in early 2009”.
McNeilly also provides information a previously undisclosed “deep depth incident” in which HMS Vanguard dived far beyond a normal safe depth. A combination of high water pressure and the submarine's low speed made it difficult for the submarine's hydroplanes generate enough lift to raise the submarine, and ballast water could not be pumped out fast enough to allow the submarine to rise. “The submarine was extremely close to being lost”, claims McNeilly.
Concern over deep depth incidents of this nature was raised in a 2009 advice note from the Defence Nuclear Safety Regulator to the Defence Board advising on selection of the nuclear propulsion plant for the proposed new 'Successor' submarine.
The paper noted that, under low power conditions, the submarine will not achieve sufficient dynamic lift from its hydroplanes, “so safety is achieved by procedural controls constraining the combinations of speed and depth, backed up by the use of ballast systems (but this may not be sufficient under all circumstances)”. It appears that during the Vanguard deep depth incident the submarine strayed beyond the speed and depth control limits, and thus got into difficulties.