A home on the rolling deep: where are Britain's submarines?

None of the Royal Navy's six attack submarines is currently at sea and some have been in port for two years: it is a catastrophic situation with no obvious solution

For readers who aren’t familiar with the defence beat (and why should you be?), here are the facts you need to know. The Royal Navy has 10 submarines. Four of these—the Vanguard class—are ballistic missile submarines which carry the UK’s independent nuclear deterrent in the form of Trident missiles. Their sole purpose is to be ready at any time to launch nuclear weapons at our enemies. They maintain what is called continuous at-sea deterrence (CASD), which means there is always, always a Vanguard-class submarine somewhere on patrol, and has been every minute of every hour of every day since 1969.

The other six vessels are attack or hunter-killer submarines, which, as the name suggests, are designed to engage and sink enemy vessels, both surface and submarine. Five of these are the newer Astute-class boats (of which two more are under construction), while the remaining submarine is an older Trafalgar-class boat, HMS Triumph, which has been in service since 1991 (the other six Trafalgars were decommissioned between 2009 and 2022 and replaced by Astutes). She is due to be taken out of service some time next year.

I’ve written at length about the Vanguard-class ballistic missile submarines. These “bombers”, as the navy colloquially refers to them because of their nuclear weapons, are ageing now, HMS Vanguard, the lead boat, having been commissioned more than 30 years ago. They are scheduled to be replaced as the platform for CASD by the new Dreadnought-class submarines being built by BAE Systems Submarines at Barrow-in-Furness, of which the lead boat, HMS Dreadnought, is expected to be in service by the early 2030s. She will be the largest submarine the Royal Navy has ever operated.

It is the hunter-killers which perform a much broader role in maintaining our maritime security and projecting force. The 2010 Strategic Defence and Security Review defined their role as follows:

They are able to operate in secret across the world’s oceans, fire Tomahawk cruise missiles at targets on land, detect and attack other submarines and ships to keep the sea lanes open, protect the nuclear deterrent and feed strategic intelligence back to the UK and our military forces across the world.

This is, self-evidently, an important element of the Royal Navy’s global role. Increasing tension with Russia has meant that Vladimir Putin is seeking to test our defences and willpower in ways deeply reminiscent of the Cold War. Last August, Royal Navy vessels and aircraft tracked a number of Russian warships close to UK territorial waters in the North Sea and the English Channel, while in November HMS Richmond shadowed the Russian frigate Admiral Grigorovich through the Channel. In May this year, five Russian warships were tracked through the Channel in just two days, and in June the Yasen-class cruise missile submarine Kazan was sighted by a Poseidon P8 maritime patrol aircraft of the Royal Air Force close to UK waters west of Scotland. The Kazan turned out to be en route to Cuba. Although the Royal Navy is understandably tight-lipped about submarine operations, as stealth and secrecy are a fundamental part of their deployment, one would expect under normal circumstances that our hunter-killer submarines would be part of this kind of observation and defence.

Given the importance of these six vessels, then, it was deeply alarming to read recently in The Times and The Sun that none of the Astute-class submarines has undertaken an operational voyage this year. Let’s be quite clear about this: five of the navy’s six hunter-killer submarines have been out of action for all of 2024.

The other boat, HMS Triumph, coming to the end of her service life, was at sea in the spring, believed to be tracking Russian submarines off the Irish coast, before appearing in Gibraltar on 21 June. There she was observed offloading Tomahawk cruise missiles, after which she returned to her home port of HMNB Devonport (she is the only submarine based there; the other nine all operate from HMNB Clyde at Faslane in Scotland). The Royal Navy has confirmed that HMS Triumph will remain in commission for at least the rest of this year, but one has to wonder whether she will be deployed again before she is taken out of service.

How can this situation have arisen? What is going on? It is worth setting it out in some detail.

1. HMS Astute was part of United Kingdom Carrier Strike Group 21 deployed to the Indian Ocean from May to December 2021. She then returned to HMNB Clyde and remained there for more than 500 days before putting to sea briefly in July 2023. She conducted some patrols but has been back at Clyde since the beginning of this year.

2. HMS Ambush has been alongside at Faslane since August 2022 and is believed to be undergoing a period of prolonged maintenance.

3. HMS Artful has been at HMNB Clyde for more than 15 months.

4. HMS Audacious undertook operations in the eastern Mediterranean in the early part of 2023, including calling at Limassol in Cyprus, and returned to Devonport in April after a 363-day deployment, the longest undertaken by an Astute-class submarine. She is currently awaiting repair and maintenance, but the Chief of the Defence Staff, Admiral Sir Tony Radakin, admitted to the House of Commons Defence Committee in July 2023 that there was no dry dock available at Devonport.

5. HMS Anson was commissioned in August 2022 and began sea trials in February 2023. In March and April this year, she undertook successful test firings of Spearfish torpedoes and Tomahawk missiles at the Atlantic Undersea Test and Evaluation Center (AUTEC) in the Bahamas then returned to HMNB Clyde. In May she was reported as being near readiness for operational deployment but she has yet to put to sea.

Inevitably this information is partial because of the Royal Navy’s unwillingness to disclose details of its submarines’ operational activities. The overriding point is this: all five Astute-class boats are currently in dock (four at Faslane and one at Devonport) rather than performing their expected roles. There are some alarming details: according to The Times, the shiplift at HMNB Clyde, used to raise the submarines out of the water, could not be used for more than a year because the company which supplied the steel hoist ropes for the device went out of business. Although the paper reports that the crane is now back in service, this means that, given the work being carried out at Devonport, the Royal Navy had no access to a dry dock for 12 months.

Another reason adduced for the inaction of the Astute boats is that priority is being given in any repairs to the Vanguard-class ballistic missile submarines. A source told The Times:

The priority is the continuous at-sea deterrent, so when there is a conflict between Astute and Vanguard-class work, it goes to the bomber. This is further challenged by visiting boats who also use the dockyard facilities.

This is particularly relevant because the Vanguard-class boats are undergoing an enormously costly £560 million deep maintenance and life extension programme. They originally had a planned life in service of 25 years, which would have seen the first, HMS Vanguard, retired in 2018. This is hugely significant work: HMS Vanguard was in dock at HMNB Devonport for seven years before returning to active service last year, while HMS Victorious arrived for her maintenance last June and is expected to complete her refit in 2028.

The need for the life extension programme is due essentially to political uncertainty and dithering. In December 2006, the Blair government issued a White Paper, The Future of the United Kingdom’s Nuclear Deterrent, which confirmed its commitment to maintaining Trident and therefore replacing the Vanguard fleet. However, it contained a caveat:

We will investigate fully whether there is scope to make sufficiently radical changes to the design of the new submarines, and their operating, manning, training and support arrangements, to enable us to maintain these continuous deterrent patrols with a fleet of only three submarines.

This was really a way of trying to save money but inevitably represented a delay in the replacement process. Almost three years later, Gordon Brown, by then Prime Minister, revealed that a reduction to three submarines was still under consideration. It was not until February 2011, more than four years after the White Paper had been published, that the Defence Secretary, Dr Liam Fox, confirmed that four submarines were required to maintain continuous at-sea deterrence. In May he announced the beginning of the “initial gate” assessment stage for the replacement for the Vanguard-class boats, which would lead to “main gate” investment decisions in 2016. Remember that HMS Vanguard’s initial operating life was supposed to end in 2018.

The House of Commons voted to approve the renewal of the nuclear deterrent and, by definition, the replacement of the Vanguard submarines, in July 2016. These successive episodes of hesitancy and temporisation before committing to what was always inevitable meant that the Vanguard-class boats would need to be kept in service for longer than planned, with the first of the successor vessels, dubbed Dreadnought-class in October 2016, anticipated to enter service in the early 2030s.

The delay and the consequent life extension programme undertaken by Babcock Marine represent additional costs, but that is not the most significant factor. The nature of continuous at-sea deterrence means that this work cannot be delayed or deferred, because the Royal Navy must have enough of the Vanguard fleet available to meet the round-the-clock commitment. There is simply no alternative. Therefore, as mentioned above, any maintenance required by an Astute-class boat is going to be a secondary priority.

All of this is going on at the same time as major redevelopment work at HMNB Devonport, with the peak construction time between late 2022 and early 2025. The outcome will be four nuclear-certified dry docks, which will be a superb resource for the Royal Navy, but first we have to get there. Number 15 Dry Dock is being converted from supporting the Trafalgar-class submarines to maintenance of the Astute-class, but work has already been going on for 18 months. After endless obfuscation and evasion, the Ministry of Defence said in a written answer last November that it expected the refurbished dock to be available some time in 2024. Number 10 Dry Dock is also being upgraded to provide routine maintenance facilities for both ballistic missile submarines and hunter-killers, but the work is currently expected to last until 2027.

This has been an unfortunate concatenation of events: the redevelopment work at Devonport, the loss of the shiplift at Faslane and the life extension to the Vanguard-class submarines have all had an impact on the Royal Navy’s ability to maintain and repair the Astute-class boats. But most of these factors were foreseeable.

The hard truth is that the current situation is little short of catastrophic. In operational terms, for almost all of 2024 the Royal Navy has had one hunter-killer submarine, HMS Triumph, and she is facing decommissioning within months. That represents an extremely grave loss of capability. One former submarine commander told The Sun:

It leaves British waters spectacularly exposed. The best thing to fight a sub is a sub… The Navy is reaping the whirlwind for a failure to make decisions earlier.

Admiral Lord West of Spithead, who was First Sea Lord and Chief of the Naval Staff from 2002 to 2006 before serving in Gordon Brown’s government as security and counter-terrorism minister, made the urgency of the situation clear as well as emphasising that it would be expensive to address.

Action must be taken now to start rectifying problems of submarine availability and that will involve money. Awaiting the outcome of the Strategic Defence Review is not an option.

There is no question of the elevated maritime threat level. In 2022, even before the invasion of Ukraine, Radakin told The Times “there’s been a phenomenal increase in Russian submarine and underwater activity over the last 20 years”, and pointed in particular to the potential vulnerability of undersea data cables. Yet the Royal Navy has virtually no presence underwater because of the lack of availability of the Astute-class boats.

While no-one expects a detailed commentary on operational matters, the Ministry of Defence, characteristically, is effusively reassuring. A spokesman said:

You’ll understand we never talk about submarine operations, but rest assured British waters are always fully protected with a range of assets including warships, patrol aircraft and submarines.

This is at least misleading if not actually untrue. British waters are not currently “fully protected” by “submarines”, because all of the navy’s hunter-killer submarines are tied up either at Faslane or Devonport. Unless the Ministry of Defence is relying on another navy to provide submarine capability, that “range of assets” does not include submarines.

This attitude is, unfortunately, endemic in the Ministry of Defence at the moment. As I pointed out in The Spectator in April, for example, the senior leadership, both civilian and military, simply wave away problems as if they do not exist and deliberately misunderstand or misinterpret questions.

When the House of Commons Public Accounts Committee concluded last month that the Ministry of Defence’s Equipment Plan contained a £17 billion shortfall between expected capabilities and resources, the department’s response was virtually to pretend the problem was not there. Instead, an MoD spokesman noted, ‘We are delivering the capabilities our forces need—significantly increasing spending on defence equipment’. The distinction between ‘more funding’ and ‘enough funding’ was seemingly lost on our top brass.

This kind of magical thinking has been on full display when the Army has talked about its plans to restructure itself into Armoured Brigade Combat Teams next year as part of the Future Soldier programme. These will be based on three armoured platforms, the Challenger 3 main battle tank, the Ajax armoured fighting vehicle and the Boxer infantry fighting vehicle. The army makes these statements in the full knowledge that the Challenger 3 programme is only just at the final production stage and will not reach initial operating capacity until 2027; only the first 93 Ajax vehicles will be available for service in 2024 and another 89 in 2025 with full operating capacity not reached until 2028 or 2029; while Boxer will not reach initial operating capacity until the end of 2025 and full operating capacity is as far off as 2032. These incompatible facts are not acknowledged.

It is hard to know what the Ministry of Defence should do. The Prime Minister has pledged in principle to increase defence spending to 2.5 per cent of gross domestic product, but, as he so far declines to set a timetable for the increase, what he calls a “cast iron commitment” is literally meaningless. The Strategic Defence Review launched last month will, Sir Keir Starmer says, provide a “roadmap” for that spending increase; the truth is, however, as I set out in CapX in May, that even spending 2.5 per cent of GDP will only plug the holes in the existing defence budget and allow the armed forces to fulfil the commitments already expected of them. It will not represent an enormous windfall.

In any event, as Lord West rightly says, the readiness of the Royal Navy’s submarine fleet cannot wait. The Strategic Defence Review is not due to report to the Defence Secretary, John Healey, with recommendations until the first half of 2025, after which the government will need to consider and respond to those recommendations. We cannot let another year go by with the Astute boats simply tied up.

There are two more Astute-class submarines under construction, HMS Agamemnon and HMS Agincourt. The former is expected to launch later this year, which means she will not be in service until 2025 at least, while the latter is likely to be commissioned some time in 2026, after which she will need to undergo sea trials before operational readiness towards the end of the decade. In total there will be seven Astute-class submarines, while HMS Triumph will go out of service in a matter of months, while will represent a net gain in the Royal Navy’s attack submarine fleet—but not for some years.

The sad conclusion is that the Ministry of Defence finds itself in a situation which is both unacceptable and seemingly irresolvable. The construction, maintenance and repair of modern nuclear submarines take years, not months, and cannot be compressed beyond a certain point. Equally, unless the government allows continuous at-sea deterrence to lapse, the work on the Vanguard-class submarines, as well as the construction of the Dreadnought-class successors, cannot be slowed or halted: and Starmer promised before the election to maintain a “nuclear deterrent triple lock”, meaning the construction of all four Dreadnought-class submarines, the maintenance of CASD and the delivery of any upgrades needed for the boats throughout their service lives.

At the same time, the facilities available at HMNB Devonport, while offering increased capacity on completion, will take as long as they take. It is hard to see a timescale that can easily be shortened, even by substantial spending, and such additional expenditure is highly unlikely, especially given the government’s current warnings of cuts in October’s Budget.

It is not realistically possible to extend HMS Triumph’s service, even if that were considered as a stopgap. From 2018 to 2022, she underwent a Revalidation and Assisted Maintenance Period (RAMP) and is already beyond her anticipated retirement date, but her nuclear reactor is coming to the end of its expected life: the only alternative to decommissioning the boat would be to refuel her, that is, replace the core of the reactor. This is a major undertaking which can last years and cost hundreds of millions of pounds, so it would not solve the availability gap nor would it be remotely sensible in financial terms given HMS Triumph’s age.

There seem to be no realistic options except for the Royal Navy to grit its teeth and weather the current storm. When all seven Astute-class boats are operational and HMNB Devonport is fully redeveloped, we will be able to breathe again for a time. Until then, the Royal Navy is lacking a capability which has not been needed as acutely since the Cold War. We are where we are, as the phrase has it, but perhaps at least the Ministry of Defence will be shocked into facing a degree of reality, and may examine the decisions and events which led to the current situation, and learn some lessons. I have to say that on that score I am not confident.