The future of Royal Navy attack submarines

On 6th February the Minister for Defence Procurement confirmed in Parliament that all 7 Astute class submarines would be completed by the end of 2026, despite the serious delay to the delivery of HMS Audacious. Here we look at the submarine programme in the medium-long term.

Trenchant lives on

The problems with HMS Audacious have been well documented and she will join the fleet sometime in early 2021, at least 17 months later than planned. This has had two immediate consequences, firstly the delivery of boat 5, HMS Anson will be delayed and secondly, it has been confirmed that HMS Trenchant will remain in service for at least another year. Trenchant was launched in 1986 and this 34-year old must be close to the end of viable operation. With an eye to the problems with the Astute programme, Trenchant underwent a 3-year refit 2013-16 described as “largest and most complex ever undertaken at Devonport” which should see her through this extra time in service. Although far from ideal, this is a sensible decision which at least ensures SSN numbers do not go below the already ‘rock-bottom’ number of 6. There will undoubtedly be additional maintenance costs involved and her ships company will have to work hard to keep this veteran boat going. It looks likely that the two other Trafalgar class boats, HMS Talent and Triumph may also have to have their decommissioning delayed slightly to cover the late arrival of HMS Anson and Agamemnon.


Scrutiny v Security

In yet another case of MoD attempting to obscure bad news, the Minister also added: “The planned In-Service Dates (ISD) for Royal Navy submarines are withheld as disclosure would, or would be likely to, prejudice the capability, effectiveness or security of the Armed Forces.” The Out of Service Dates (OSD) which were public information just a few years ago are already being withheld but this is a more serious development that will further reduce accountability in the submarine programme. Using newly-invented security concerns to make inconvenient truths less obvious is a shabby way to treat the taxpayer and we would urge MPs and the Defence Select Committee to scrutinise submarine delivery with extra care. Meanwhile the head of the Submarine Delivery Agency, Ian Booth was awarded a £185K annual performance bonus. (Greater than the annual salary of the First Sea Lord or even the Prime Minister). Mr Booth is undoubtedly a highly competent executive with a track record delivering the aircraft carrier project, but the results from the SDA are not yet worthy of congratulation for anyone. The real ‘performers’ are submariners at the sharp end who have to live with the effects of delays and the broken timelines, struggling to get their boats out on patrol.

The commitment to deliver all four of the remaining Astute-class boats by 2026 is a small crumb of comfort in this much-delayed programme. The delays to Audacious must be absorbed in the schedule because there cannot be any further hold-ups at Barrow in the production of following Dreadnought class SSBNs. In BAE Systems’ recent report to its shareholders, despite having 4 Astute-class boats still under construction, it announced that work on the Dreadnought class already forms a greater part of their revenue. Manufacture of the second boat, HMS Valiant, began in September 2019 and it is interesting to note they are designed with a service life of around 35-40 years, an increase of around 25% over their Vanguard-class predecessors.

Astute successor – SSN(R)

Maritime Underwater Future Capability (MUFC) is the RN’s program to consider replacements for the Astute class. The project began the initial Concept Phase in early 2018 but was suspended in May 2018 for two years. This was probably not driven by financial considerations but the delays to the Astute and Dreadnought programme that means Barrow will not be ready to construct a new class of submarine until the late 2030s. MUFC work appears to be about to resume and the successor to the Astute class is now provisionally referred to as SSN(R). DE&S recently began recruiting project managers to work for the ‘Astute Replacement Nuclear Submarine SSN(R) team’. How undersea warfare will look in the 2040s and beyond is hard to predict. Despite the rapid growth of unmanned systems and potential improvements in detection technology, the promise of an entirely ‘transparent ocean’ may never be fulfilled. The manned submarine has a big future, although it is likely to rely increasingly on a payload of its own unmanned systems to extend its reach.

SSN(R) is only at a very early concept stage and nothing official is in the public domain. Respected analyst, H I Sutton, believes it will be around 25% bigger than the Astute and have much in common with the Dreadnought class. Its extra size will allow for the fitting of the PWR-3 reactor, heavier armament and defensive countermeasures. An enlarged ‘hangar’, similar to the Astute’s Chalfont DDS, may also be fitted for unmanned systems. It is also likely to have the X-form tail of Dreadnought, which is more complex to build but is quieter than the Astute’s conventional tail. From an industrial perspective, if work to build SSN(R) can begin straight away on the ‘hot’ Dreadnought production line then it should be much more painless than the Astute project.



A boat 25% larger than Astute would require further upgrades to the dry-docks in Devonport. At present these facilities are still only certified for Trafalgar class boats and not yet able to take an Astute. For now, all dry-docking has to be done at the ship-lift facility in Faslane. This is manageable while there are only 3 active Astutes that can be fitted around the docking requirements of the 3 active Vanguard boats. Once there are 7 Astute boats in service, the dry dock in Devonport will become critical for their support. As SSN(R) is unlikely to enter service before the early 2040s it is possible that HMS Astute and will require refuelling and life extension in the mid-2030s as her PWR-2 Core H reactor has a theoretical 25-year lifespan. Babcock is currently having problems refuelling HMS Vanguard, possibly because her Core H reactor was not originally intended to be refuelled.

Tell us more

This article demonstrates that at least a limited insight into the highly complex submarine programme may be gathered from information in the public domain. What is more concerning is the almost total blackout of official information about the activities of the modern submarine service. The nuclear deterrent and undersea warfare is obviously one of the most sensitive and secretive aspects of UK defence and publicity must be carefully controlled and censored. But with imagination, time-delay and careful management, it is quite possible to promote the outstanding work of the Silent Service to public and politicians. There was actually more publicity about submarines during the intense operations of the Cold War than there is today, in the last decade there has been an ever-decreasing explanation of the fine work of the service and the product that they can deliver. This is not an oversight by the RN news teams but the result of a deliberate policy directive from a senior level.

The last official story about the submarine service that could be described in any way as ‘operational’ was HMS Trenchant surfacing at the North Pole nearly two years ago. Otherwise, news coverage gives the impression that submariners spend all their time participating in charity bike rides or rowing events. Arguably this silence leads to a lack of understanding about the purpose and benefits of submarines and the void may be filled by those with an agenda to depict them as sinister and unjustifiably expensive. The bad news about the problems in the submarine industrial enterprise could also be counterbalanced by highlighting the benefits of operational SSNs to the nation. While OPSEC must always be the priority, if the RN wants to recruit more people and receive more resources for the undersea domain, then it must start talking about its submarines and the threats they can defeat.