Through open-source observations, it is clear that none of the Royal Navy’s six commissioned SSNs are at sea at the time of writing. As part of normal maintenance cycles several boats could be expected to be in harbour but it is unusual for the entire force to be alongside.
HMS Triumph recently returned to Devonport following a patrol lasting more than 3 months, most likely in the Eastern Mediterranean. Previously HMS Audacious spent 403 days away from the UK, mostly in the same region (crew were rotated during the deployment), arriving at Devonport in March 2023. The patrols were likely demanding, extremely helpful to the NATO cause and the crews should be congratulated. Unfortunately, as Admiral Radakin admitted to the Defence Select Committee on 5th July, Audacious is now stuck alongside at Devonport pending maintenance because a suitable dry dock is not available.
It is difficult to account for the exact status of the other 4 boats as this kind of information is not in the public domain but HMS Astute, Ambush, Artful and Anson have all been observed together in Faslane this week. After spending more than 500 days out of action following participation in CSG21, HMS Astute briefly put to sea in July. The newest boat, HMS Anson arrived at Faslane for the first time in February and it might be expected she would be operational with sea trials and workup complete but neither she nor HMS Artful appear to have been active for several months. HMS Ambush has been inactive for more than a year.
At least one boat is likely to deploy soon, possibly in support of the upcoming CSG23 deployment and the unusual scenario of all the SSNs being alongside may be short-lived. Whether it is a matter of inadequate material state, support infrastructure issues, crew shortages or a combination of these is unclear but if all was well, more could be expected from these relatively new boats. The RN initiated Project RESOLUTION in 2021 intended to increase submarine availability but progress appears to be limited.
At Devonport work is now well underway to upgrade number 10 dock to the standards needed to support future SSBN and SSN refits and maintenance. This is a major project that will not be finished for some time as the dock has to be completely reconfigured and reinforced to meet the ever-more stringent regulations for nuclear facilities. When eventually completed, this will relieve a major bottleneck in submarine support as there is currently only the shiplift at Faslane and number 15 dock in Devonport where SSNs can be taken out of the water. The ageing SSBNs have priority on the shiplift and number 9 dock at Devonport is permanently occupied with major refits of the Vanguard class. Number 14 dock is slowly being prepared for the disposal of decommissioned submarines. Even number 15 dock is currently unavailable as it is being converted from supporting Trafalgar class boats to Astute class, hence the delay to starting work on Audacious.
Part of the great advantage of owning submarines is the uncertainty caused in the mind of adversaries, knowing that just a single boat is at sea can be enough to exert a deterrent effect, especially as the range and speed of SSNs means they can pose a threat over an enormous area. It is obviously undesirable to have the entire force in harbour simultaneously if it can be avoided, especially when there is no shortage of tasks they could be doing.
One of the SSNs is usually required to ‘delouse’ the nuclear deterrent submarines (SSBNs) particularly when starting or ending a patrol and is transiting through more confined areas. Sanitising the waters around the boat to ensure it is not trailed by unwanted intruders has been a standing task for RN SSNs since the deterrent patrols began in the late 1960s. Given the sensitivity of their signatures, this is not a job that can be ‘outsourced’ to foreign allies.
A sustained submarine presence in the eastern Mediterranean would obviously be ideal as it is a key maritime theatre in terms of monitoring the Russian presence close to Syria and the Black Sea. Reports of high levels of Russian submarine activity in the North Atlantic and close to the UK continue unabated and now is an especially unfortunate moment to be lacking the means to counter them. The best way to find a submarine is usually with another submarine. The UK’s contribution to monitoring this threat should comprise more than a single frigate on Towed Array Patrol Ship (TAPS) duty or a few P-8A Poseidon sorties.
It is bad enough that the Submarine Service has become so small but its effectiveness is clearly being further eroded by the inability to get boats to sea. Major improvements will be needed if the RN is to deliver on the AUKUS promises of more frequent submarine visits to Australia and a boat permanently based in Perth from 2027.
Thanks to Dave Cullen and Michael Cuthbert for their contributions to this article. Main image: HMS Triumph on her way into Devonport on 27th August after more than 3 months away. (Photo: Tom Leach)