 Artist's rendering ofDreadnought-class submarine | |
| Class overview | |
|---|---|
| Builders | BAE Systems,Barrow-in-Furness, England |
| Operators |  Royal Navy |
| Preceded by | Vanguard class |
| Cost | |
| Built | First expected by early 2030s[3] |
| Planned | 4 |
| Building | 4 |
| Active | 0 |
| General characteristics | |
| Type | Nuclear-poweredballistic missile submarine |
| Displacement | 17,200 t (16,900 long tons; 19,000 short tons) |
| Length | 153.6 metres (504 ft)[4] |
| Propulsion | Rolls-Royce PWR3nuclear reactor, turbo-electric drive,pump-jet |
| Range | Limited only by food and mechanical components |
| Complement | 130 |
| Armament |
|
TheDreadnought class is the future replacement for theRoyal Navy'sVanguard class ofballistic missile submarines.[1] Like their predecessors they will carryTrident II D-5 missiles.[5] TheVanguard submarines entered service in the United Kingdom in the 1990s with an intended service life of 25 years.[6] Their replacement is necessary for maintaining a continuous at-seadeterrent (CASD), the principle of operation behind theTrident system.[7]
Provisionally named "Successor" (being the successor to the Vanguard class SSBNs), it was officially announced in 2016 that the first of class would be namedDreadnought, and that the class would be theDreadnought class.[8][9] The next three boats will be calledValiant,[10]Warspite andKing George VI.[11]
Since the retirement of the lastRoyal Air ForceWE.177 nuclear bomb in 1998, the British nuclear arsenal has been wholly submarine-based. It is intended to deter a potential enemy because they cannot ensure eliminating the entire stockpile in afirst strike if aballistic missile submarine remains undetected.Trident missiles are currently equipped with Holbrook warheads, thought to be technically similar to the AmericanW76. There are plans to replace this with theAstraea A21/Mk7.[12]
Since theStrategic Defence Review (SDR) of 1998, the UK has maintained a stockpile of around 215 warheads, with around 120 active (usable). Under the continuous at sea deterrence policy, at least oneVanguard-class SSBN is kept on patrol with up to 16 Trident missiles sharing up to 48 warheads from the stockpile at any given time. The SDR considered this was the minimum number of warheads adequate for deterrence. It is collectively known as the Trident system.[13] The majority of this system is based inScotland atHMNB Clyde (HMSNeptune), which includes theFaslane home of theVanguard submarines, and atRNAD Coulport onLoch Long. The oldestVanguard-class submarine had been expected to remain in service until 2019 without a refit.[14] Since 1998, the system has also provided the Government with the option of a lower-yield, "sub-strategic" nuclear strike capability.[15] Under both theStrategic Defence and Security Review 2010 and theStrategic Defence and Security Review 2015, the total number of warheads for the submarine on patrol would be 40 and the maximum total number of ballistic missiles would be 8.[16][17] The2021 Integrated Review announced, however, along with a lift on the cap on warheads to no more than 260 (from 180 planned in previous reviews), any numbers or information on deployed missiles and warheads will no longer be provided, under a policy of "deliberate ambiguity".[18]
In May 2011 the government approved the initial assessment phase for the new submarines and authorised the purchase of long lead-time items including steel for the hulls. In May 2015 theConservative Party won the UK General Election on a manifesto which included a commitment to maintaining a CASD with four Successor submarines.[19] The final decision to commit to the Successor programme was approved on 18 July 2016 when theHouse of Commons voted to renew Trident by 472 votes to 117.[20] Successor generated controversy because of its cost,[21] and because some political parties and campaign groups such as theCampaign for Nuclear Disarmament (CND) andTrident Ploughshares oppose the retention of CASD or any nuclear weapons by the UK on moral or financial grounds.[22][23]
The programme is managed by a newSubmarine Delivery Agency (SDA), established on 3 April 2017 within theMinistry of Defence (MOD)Defence Equipment and Support (DE&S) organisation.BAE Systems andRolls Royce are the programme's Tier One industrial partners.[24]
In 2011, the programme's Initial Gate report estimated costs at £25 billion. In 2015, the programme was estimated to cost £31 billion including estimated future defence inflation, design, testing and construction of the US-UK Common Missile Compartment and modernisation of shipyard facilities in Barrow, with £10 billion of additional contingency set aside. In March 2023, £2 billion of the contingency fund had been accessed to reprofile spending and bring construction forward.[24] These costs do not include the relatedTrident missile renewal, new infrastructure projects at the re-nationalisedAtomic Weapons Establishment, and new nuclear fuel production facilities at Rolls-Royce.[24]
Once in service, annual in-service costs are expected to be approximately 6% of the defence budget (about £3 billion).[24]
Studies by theNuclear Information Service and theCampaign for Nuclear Disarmament have suggested that the MOD cost presentation is under-estimating replacement programme costs. Including all related costs, including new infrastructure investment and decommissioning costs, and 30 years of in-service costs, they estimate a cost in the region of £172 to £205 billion.[24]Crispin Blunt, Chair of theForeign Affairs Select Committee, estimated in July 2016 that the renewed deterrent lifetime cost would be £179 billion.[25]
A January 2018, theNational Audit Office expressed concern about the programme's spending profile, including that it was "unaffordable in the early years of the project" within the MOD allocated budget.[24][26] Subsequently the MOD moved £300 million into the Dreadnought programme from elsewhere, and later the2018 budget added £1 billion to the defence budget, 40% of which went to the Dreadnought programme. The2020 Spending Review allocated an extra £16.5 billion to the defence budget over 2020 to 2025, in part to "continue the renewal of the UK's nuclear deterrent".[24]
The submarines have an intended service life of around 35 to 40 years, an increase of around 50% over the previous class.[27] The submarines will each have a crew of 130, including three chefs and a doctor. There will be separate female quarters,[28] a gym space, classroom and a lighting system simulating the time of day on board.[29] They will be powered byRolls-Royce'sPWR3 (Pressurised Water Reactor 3), compared to the PWR2 used onVanguard- andAstute-class submarines.[28] Although PWR2 and PWR2b (a derivative with improvements) designs were considered, "the requirement to continually improve our performance and to meet 'ALARP' is only met through PWR3".[30] so the PWR3 was chosen for improved safety, easier operations, longer service life and reduced maintenance costs, with 30% fewer parts.[31][32] They will be equipped with X-rudders, in a first on British submarines, to reduce noise, especially at high speeds, in front of thepumpjet.[33] UnlikeVanguard-class submarines, control of movement will use "fly-by-wire" technology, with the Active Vehicle Control Management (AVCM) system from BAE Systems.[34][35] As inAstute-class andTrafalgar-class submarines, they will be equipped with theSonar 2076 system fromThales.[36] They will each have three missile compartments with four missile tubes each (quad packs), for a total of twelve missile tubes. These share a common design with those on AmericanColumbia-class submarine, as part of the "Common Missile Compartment" (CMC) scheme. There will be five deck levels.[18][28][29]
Construction started in late 2016 at theBarrow-in-Furness shipyard operated byBAE Systems Submarines, when the first submarine was provisionally expected to enter service in 2028.[37] The start of construction of the second phase was announced in May 2018.[38]
In October 2018,Cammell Laird was awarded a contract to manufacture 29 non-pressure hull sections inBirkenhead.[29] The MOD said in December 2018 that construction of the first submarine was on schedule and within budget.[39] In April 2021,The Sunday Times reported that delays on theAstute-classsubmarines may impact theDreadnought class, which will be built in the samedock hall. Related concerns are a 19-month delay to an extension of the Barrow facility and a five-year delay to aRolls-Royce factory which will build the nuclear reactors.[40] However, the MOD commented that "theDreadnought programme remains on track to deliver to schedule, with the first in class expected to enter service in the early 2030s."[40]
Thales Glasgow was awarded a £193 million contract in July 2023, to provideoptronic masts, similar to those in use onAstute class.[41]General Dynamics Mission Systems is to provide and maintain fire control systems for bothDreadnought- and AmericanColumbia-classsubmarines.[42] Seventy-five missile tube assemblies forDreadnought- andColumbia-class submarines will be manufactured byBabcock inRosyth andBristol.[43]Northrop Grumman will provide the launcher subsystem hardware for the common missile compartments in both platforms, under a $458 million contract in June 2022.[31] In January 2025, Rolls Royce was awarded a £9 billion contract by the MOD, covering research, design, manufacture and support of all nuclear reactors in Royal Navy submarines. The contract, named "Unity", covers a period of 8 years, and will continue to support the delivery of the reactors forDreadnought-class submarines. Defence SecretaryJohn Healey said "This investment in Britain’s defence will deliver a long-term boost to British business, jobs and national security."[44][45]
| Name | Builder | Steel cut | Laid Down | Launched | Commissioned | Status |
|---|---|---|---|---|---|---|
| Dreadnought | BAE Systems Submarines, Barrow-in-Furness | 6 October 2016[46] | 20 March 2025 | Expected early 2030s | Under construction | |
| Valiant | September 2019[47] | Under construction | ||||
| Warspite | 9 February 2023[48] | Under construction | ||||
| King George VI | 22 September 2025[49] | Under construction |
