Editing Vanguard-class submarine

{{Short description|Royal Navy ballistic missile submarine class}}
{{Other ships|HMS Vanguard}}
{{Use dmy dates|date=June 2020}}
{|{{Infobox ship begin}}
{{Infobox ship image
| Ship image = Vanguard class SSBN.svg
| Ship caption = ''Vanguard''-class SSBN profile
}}
|-
{{Infobox ship image
| Ship image = Vanguard at Faslane 03.jpg
| Ship caption = HMS ''Vanguard'' at [[HMNB Clyde|Faslane]], 2010
}}
{{Infobox ship class overview
| Name = 
| Builders = [[Vickers Shipbuilding and Engineering]], [[Barrow-in-Furness]], England
| Operators = {{navy|United Kingdom}}
| Class before = {{sclass|Resolution|submarine|4}}
| Class after = {{sclass|Dreadnought|submarine|4}}
| Subclasses = 
| Cost = *{{ShipCost|GBR|12.153|b|year=1995|quantity=4|ref=<ref>[http://www.nuclearinfo.org/documents/hndm/hartley.pdf Hartley (PDF)] {{Webarchive|url=https://web.archive.org/web/20120317122425/http://www.nuclearinfo.org/documents/hndm/hartley.pdf |date=17 March 2012 }} nuclearinfo.org</ref>}} 
*{{ShipCost|GBR|3.03825|b|year=1995|r=2|quantity=1}}
| Built range = 1986–1998
| In service range = 1993–present
| In commission range = 
| Total ships building = 
| Total ships planned = 
| Total ships completed = 4
| Total ships cancelled = 
| Total ships active = 4
| Total ships laid up = 
| Total ships lost = 
| Total ships retired = 
| Total ships preserved = 
}}
{{Infobox ship characteristics
| Hide header = 
| Header caption = 
| Ship type = [[Nuclear marine propulsion|Nuclear-powered]] [[ballistic missile submarine]]
| Ship displacement = Submerged: {{convert|15900|t|abbr=on}}
| Ship length = {{convert|149.9|m|ftin|abbr=on}}
| Ship beam = {{convert|12.8|m|ftin|abbr=on}}
| Ship draught = {{convert|12|m|ftin|abbr=on}}
| Ship power = 
| Ship propulsion = *1 × [[Rolls-Royce PWR#PWR2|Rolls-Royce PWR2 nuclear reactor]],
*2 × [[General Electric Company|GEC]] turbines; {{convert|27500|shp|MW|abbr=on}}
*1 × shaft, [[Pump-jet|pump jet propulsor]]
*2 × auxiliary retractable propulsion motors
*2 × Allen turbo generators&nbsp;(6 MW)
*2 × [[Paxman (engines)|Paxman]] diesel alternators;&nbsp;{{convert|2700|shp|MW|abbr=on}}
| Ship speed = Over {{convert|25|knot|km/h mph|lk=in}}, submerged
| Ship range = Limited only by food and mechanical components
| Ship endurance = 
| Ship test depth = 
| Ship complement = 135
| Ship sensors = * [[BAE Systems]] [[SMCS]]
* [[Kelvin Hughes]] Type 1007 I-band navigation radar
* [[Thales Underwater Systems]] Type 2054 composite sonar suite comprising:&nbsp;
** [[Marconi Electronic Systems|Marconi]]/[[Ferranti]] Type 2046 towed array sonar&nbsp;
** Type 2043 hull-mounted active and passive search sonar&nbsp;
** Type 2082 passive intercept and ranging sonar
* [[Pilkington Optronics]] CK51 search [[periscope]]
* Pilkington Optronics CH91 attack periscope
| Ship EW = * Two SSE Mk10 launchers for Type 2066 and Type 2071 torpedo decoys
* [[Electronic warfare support measures|RESM]] Racal UAP passive intercept
| Ship armament = * 4 × [[British 21-inch torpedo|21-inch (533 mm)]] [[torpedo tube]]s for: [[Spearfish torpedo|Spearfish]] heavyweight torpedoes
* 16 × ballistic missile tubes for: [[Lockheed Corporation|Lockheed]] [[UGM-133 Trident II|Trident II D5]] [[submarine-launched ballistic missile|SLBM]]s with up to 12 [[Multiple independently targetable reentry vehicle|MIRVed]] Holbrook Mk-4A (100&nbsp;kt<sub>TNT</sub>) nuclear warheads each
| Ship notes = 
}}
|}

The '''''Vanguard'' class''' is a class of [[Nuclear submarine|nuclear-powered]] [[ballistic missile submarine]]s (SSBNs) in service with the [[Royal Navy]].<ref>[https://www.royalnavy.mod.uk/the-equipment/submarines/ballistic-submarines/vanguard-ballistic Royal Navy Vanguard class submarine], royalnavy.mod.uk</ref> The class was introduced in 1994 as part of the [[Trident nuclear programme]], and comprises four vessels: {{HMS|Vanguard|S28|2}}, {{HMS|Victorious|S29|2}}, {{HMS|Vigilant|S30|2}} and {{HMS|Vengeance|S31|2}}, built between 1986 and 1999 at [[Barrow-in-Furness]] by [[Vickers Shipbuilding and Engineering]], now owned by [[BAE Systems]].<ref name="Janes">''Jane's Fighting Ships, 2004–2005''. Jane's Information Group Limited. p. 794. {{ISBN|0-7106-2623-1}}.</ref> All four boats are based at [[HMNB Clyde|HM Naval Base Clyde (HMS ''Neptune'')]], {{convert|40|km|mi|abbr=on}} west of [[Glasgow]], Scotland.

Since the decommissioning of the [[Royal Air Force]] [[WE.177]] free-fall [[thermonuclear weapon]]s during March 1998, the four ''Vanguard'' submarines are the sole [[Weapons platform|platforms]] for the [[Nuclear weapons and the United Kingdom|United Kingdom's nuclear weapons]].<ref name="strategicdefencereview">[http://webarchive.nationalarchives.gov.uk/20121026065214/http://www.mod.uk/NR/rdonlyres/65F3D7AC-4340-4119-93A2-20825848E50E/0/sdr1998_complete.pdf Strategic Defence Review] [[White Paper]] of July 1998, published by [[The National Archives (United Kingdom)|National Archives]] – re-access made 2020-03-09</ref> Each submarine is armed with up to 16 [[UGM-133 Trident II]] [[Submarine-launched ballistic missile|missiles]]. The class is scheduled to be replaced starting in the early 2030s with the [[Dreadnought-class submarine|''Dreadnought''-class]] submarine.<ref name="auto">{{cite web |url=http://www.itv.com/news/2016-07-18/everything-you-need-to-know-about-trident-britains-nuclear-deterrent/ |title=Everything you need to know about Trident – Britain's nuclear deterrent |author=<!--Staff writer(s); no by-line.--> |date=18 July 2016 |website=ITV News |publisher=ITV plc |access-date=20 July 2016 |quote=The £40 billion construction of a new fleet, Successor, could begin this year and be operational by 2028, however it will more than likely be at a later date given the MoD's complex procurement procedures. while the current fleet will be phased out by 2032.}}</ref><ref>{{cite news|title=BAE Systems to begin building new British nuclear submarines|url=https://www.reuters.com/article/britain-defence-idUSL8N1C709W|access-date=1 October 2016|work=Reuters|date=1 October 2016}}</ref>

==Development==
===Trident programme===
{{Main|Trident nuclear programme}}
Beginning in the late 1960s, the United Kingdom operated four {{sclass|Resolution|submarine|1}}s, each armed with sixteen US-built [[UGM-27 Polaris|UGM-27 Polaris missiles]]. The Polaris missile was supplied to Britain following the terms of the 1963 [[Polaris Sales Agreement]]. This nuclear deterrent system was known as the [[UK Polaris programme]]. In the early 1980s the British government began studies examining options for replacing the ''Resolution''-class submarines and their Polaris missiles, both of which would be approaching the end of their service lives within little over a decade.<ref name="1980DefenceCouncil">{{cite journal|last1=PYM|first1=Francis|title=The Future United Kingdom Strategic Nuclear Deterrent Force|journal=Ministry of Defence|date=July 1980|url=http://fc95d419f4478b3b6e5f-3f71d0fe2b653c4f00f32175760e96e7.r87.cf1.rackcdn.com/6AC6FE79AE5E485DB3A2B579B6AE0654.pdf|access-date=1 December 2016}}</ref> On 24 January 1980, the House of Commons backed government policy, by 308 votes to 52, to retain an independent nuclear deterrent. Options that were examined included:<ref name="1980DefenceCouncil"/>
*A British designed and built ballistic missile; Although Britain had had no capability in this field since the 1960s, it was considered "not to be impossible". However, it would be very expensive, would be full of uncertainty and would not be available within the required time period. Thus the option was considered "unattractive".
*Retain Polaris, but fitted on a new submarine class; This option would have a cheaper "initial capital cost", but would lack in terms of required capability and reliability. Also, it was concluded that any initial capital savings would have been lost beyond the 1990s, due to the high cost of sustaining a small stockpile of bespoke missiles kept only in British service.

A European solution and the US [[UGM-73 Poseidon]] were also briefly considered, but ultimately rejected, primarily on capability, cost and uncertainty grounds.<ref name="1980DefenceCouncil"/> The clear favourite was the [[UGM-96 Trident I]], which as well as being a cost-effective solution – given the US would also operate the missile in vast numbers – also delivered the overall best long-term capability insurances against Soviet advancements in [[ballistic missile defence]].<ref name="1980DefenceCouncil"/> Subsequently, on 10 July 1980, the then Prime Minister [[Margaret Thatcher]] wrote to US President [[Jimmy Carter]] requesting the purchase of Trident I missiles on a similar basis as the 1963 Polaris Sales Agreement. However, following the acceleration of the US [[UGM-133 Trident II]] missiles, Thatcher wrote to US President [[Ronald Reagan]] in 1982 requesting the United Kingdom be allowed to procure the improved system instead. An agreement was made in March 1982 between the two countries,<ref>[http://www.reagan.utexas.edu/archives/speeches/1982/31182b.htm Letter to Prime Minister Margaret Thatcher of the United Kingdom Confirming the Sale of the Trident II Missile System to the Her Country] {{Webarchive|url=https://web.archive.org/web/20100913055759/http://www.reagan.utexas.edu/archives/speeches/1982/31182b.htm |date=13 September 2010 }} 11 March 1982</ref> and under the agreement, Britain made a 5% research and development contribution.<ref name=NAO-1987>{{cite book|title=Ministry of Defence and Property Services Agency: Control and Management of the Trident Programme|publisher=[[National Audit Office (United Kingdom)|National Audit Office]]|date=29 June 1987|pages=Part 4|isbn=0-10-202788-9|no-pp=true}}</ref>

===Design and construction===
[[File:BAE Systems from Walney.jpg|thumb|left|The {{convert|25000|m2|abbr=on}} [[Devonshire Dock Hall]] indoor shipbuilding complex]]
The ''Vanguard'' class were designed in the early 1980s by the Ministry of Defence, acting in one of its last Royal Navy warship design authority roles. The guidance drawings were then supplied for detailed design development by [[Vickers Shipbuilding and Engineering]] (VSEL) based at [[Barrow-in-Furness]], now [[BAE Systems Maritime – Submarines]]. They were designed from the outset as nuclear-powered ballistic missile submarines, able to accommodate the UGM-133 Trident II missiles. As such, the missile compartment is based on the same system used on the American {{sclass|Ohio|submarine|4}}, which is also equipped with the UGM-133 Trident II. This requirement led to the ''Vanguard''-class design being significantly larger than the previous Polaris-equipped ''Resolution'' class, and at nearly 16,000 tonnes they are the largest submarines ever built for the Royal Navy.

Due to the large size of the ''Vanguard''-class, the [[Devonshire Dock Hall]] in Barrow-in-Furness was built between 1982 and 1986 specifically for the construction of the boats.<ref name="DDH">{{cite news |date=2 September 2011 |title=In pictures: Submarine 'shed' in Cumbria marks 25th year |work=BBC News |url=https://www.bbc.co.uk/news/uk-england-cumbria-14762995 |access-date=1 December 2016}}</ref>

Beginning in 1985, both [[HMNB Clyde]] and the [[RNAD Coulport|Royal Naval Armaments Depot Coulport]] at Faslane underwent extensive redevelopment in preparation for the ''Vanguard'' class submarines and Trident II missiles. [[Rosyth Dockyard|Rosyth dockyard]] also underwent significant redevelopment. The work included enhanced "handling, storage, armament processing, berthing, docking, engineering, training and refitting facilities" at an estimates cost of £550 million.<ref>{{cite web|title=Trident|url=https://api.parliament.uk/historic-hansard/written-answers/1985/jan/15/trident-1|publisher=Hansard, 15 January 1985|work=[[Hansard|Parliamentary Debates (Hansard)]]|date=15 January 1985|access-date=1 December 2016}}</ref>

Prime Minister Thatcher laid the keel of the first boat, HMS ''Vanguard'', on 3 September 1986 at the Devonshire Dock Hall.<ref>{{cite web |url= http://www.astuteclass.com/2011/09/ddh-celebrates-25th-birthday/ |title=DDH celebrates 25th birthday &#124; Astute Class Submarine – BAE Systems Maritime – Submarines |work=astuteclass.com |year=2012 |access-date=27 August 2012}}</ref> ''Vanguard'' was [[Ship naming and launching|launched]] in 1992 and [[Ship commissioning|commissioned]] in 1993. The year 1992 saw a debate over whether the fourth vessel, ''Vengeance'', should be cancelled; however, the Ministry of Defence ultimately ordered it in July 1992<ref>{{cite news |date=1992-07-08 |title=Trident order raises arms doubts |newspaper=The Guardian |location=London }}</ref> and it was commissioned in 1999.

===Replacement===
{{Main|Dreadnought-class submarine}}

The Vanguard class had an originally intended service life of 25 years.<ref>{{Cite web |last=Service |first=Nuclear Information |date=2023-08-07 |title=HMS Vanguard leaves Devonport after 7 years of maintenance |url=https://www.nuclearinfo.org/article/hms-vanguard-leaves-devonport-after-7-years-of-maintenance/ |access-date=2024-05-28 |website=Nuclear Information Service |language=en-GB}}</ref> This would put the retirement dates for the class at 2018, 2020, 2021, 2024.<!-- Feel free to move this bit somewhere better in the article, but I feel this should at least be mentioned somewhere on this page. -->

On 4 December 2006, then Prime Minister [[Tony Blair]] revealed plans to spend up to £20&nbsp;billion on a new generation of ballistic missile submarines to replace the ''Vanguard'' class. In order to reduce costs and show Britain's commitment to the [[Treaty on the Non-Proliferation of Nuclear Weapons|Non-Proliferation Treaty]], Blair suggested that submarine numbers could be cut from four to three, while the number of nuclear warheads would be cut by 20% to 160.<ref name="WhitePaper">{{citation |url=http://www.mod.uk/NR/rdonlyres/AC00DD79-76D6-4FE3-91A1-6A56B03C092F/0/DefenceWhitePaper2006_Cm6994.pdf|title= The Future of the United Kingdom's Nuclear Deterrent|date=4 December 2006|publisher=[[Ministry of Defence (United Kingdom)|Ministry of Defence]] | access-date =5 December 2006}}</ref> On 23 September 2009, then Prime Minister [[Gordon Brown]] confirmed that this [[Rule of thirds (military)|reduction to three]] submarines was still under consideration.<ref>{{cite news| url=http://news.bbc.co.uk/1/hi/uk_politics/8270092.stm| author=BBC News| title=Brown move to cut UK nuclear subs | access-date=23 September 2009 | date=23 September 2009}}</ref> In February 2011, the [[Secretary of State for Defence|Defence Secretary]] [[Liam Fox]] stated that four submarines would be needed if the UK was to retain a credible nuclear deterrent.<ref>{{cite news| url=https://www.bbc.co.uk/news/uk-scotland-12504517 |work=BBC News  | title=Trident nuclear fleet cuts ruled out by Liam Fox | date=23 February 2011}}</ref> On 18 May 2011 the British government approved the initial assessment phase for the construction of a new class of four submarines, paving the way for the ordering of the first long-lead items and preparations for the main build to begin in the future. This new class of submarine, now known as the [[Dreadnought-class submarine|''Dreadnought'' class]], will retain the current Trident II missiles, and will incorporate a new [[Rolls-Royce PWR#PWR3|'PWR3']] nuclear reactor as well as technology developed for the {{sclass|Astute|submarine|0}} nuclear-powered fleet submarines of the Royal Navy.

A vote on the Trident renewal programme was held in the [[House of Commons of the United Kingdom|House of Commons]] on 18 July 2016, and determined that the UK should proceed with construction of the next generation of submarines. The motion passed with a significant majority of 472 MPs voting in favour and 117 against. The MoD put the cost of building, testing and commissioning the replacement vessels at £31&nbsp;billion (plus a contingency fund of £10&nbsp;billion) over 35 years, or about 0.2&nbsp;per&nbsp;cent of government spending, or 6&nbsp;per&nbsp;cent of defence spending, every year.<ref name="modfeb16">{{cite web|url=https://www.gov.uk/government/publications/uk-nuclear-deterrence-factsheet/uk-nuclear-deterrence-what-you-need-to-know|title=UK nuclear deterrence: what you need to know|publisher=Ministry of Defence|date=26 February 2016|access-date=1 March 2016}}</ref> It is expected the new fleet of submarines will come into operation starting 2028 at the earliest<ref name="auto"/> and certainly by the 2030s.<ref>{{cite news|url=https://www.bbc.co.uk/news/uk-politics-36830923|title=MPs approve Trident renewal|date=18 July 2016|work=BBC News|access-date=18 July 2016|quote=MPs approve Trident renewal|author=<!--Staff writer(s); no by-line.-->}}</ref> The ''Dreadnought'' class will extend the life of the Trident programme until at least the 2060s.<ref>{{cite news|url=https://www.independent.co.uk/news/theresa-may-trident-renewal-nuclear-attack-threat-labour-free-vote-a7141826.html |archive-url=https://ghostarchive.org/archive/20220811/https://www.independent.co.uk/news/theresa-may-trident-renewal-nuclear-attack-threat-labour-free-vote-a7141826.html |archive-date=11 August 2022 |url-access=subscription |url-status=live|title=Theresa May warns threat of nuclear attack has increased ahead of Trident vote|author=Tom Peck|date=18 July 2016|access-date=18 July 2016|work=Independent}}</ref>

==Characteristics==
===Weapons and systems===
[[File:Trident II missile image.jpg|thumb|Test launch of a [[Trident missile|Trident II]] missile by a ''Vanguard''-class submarine]]
The ''Vanguard''-class submarines are equipped with 16 ballistic missile tubes. However, as of the [[Strategic Defence and Security Review 2010|2010 Strategic Defence and Security Review]], the Royal Navy loads only eight of the missile tubes with the Trident II submarine-launched ballistic missiles, each armed with up to eight nuclear warheads. In addition to the missile tubes, the submarines are fitted with four 21&nbsp;inch (533&nbsp;mm) [[torpedo tube]]s and carry the [[Spearfish torpedo|Spearfish heavyweight torpedo]],<ref>{{cite web| url=http://www.royal-navy.mod.uk/server/show/nav.2420| author=Royal Naval Website| title=Vanguard Class Ballistic Subs (SSBN)| access-date=18 June 2007| archive-url=https://web.archive.org/web/20070623085113/http://www.royal-navy.mod.uk/server/show/nav.2420| archive-date=23 June 2007| url-status=dead}}</ref> allowing them to engage submerged or surface targets at ranges up to {{convert|65|km|mi nmi}}. Two SSE Mark 10 launchers are also fitted, allowing the boats to deploy Type 2066 and Type 2071 decoys, and a UAP Mark 3 [[electronic support measures]] (ESM) intercept system is carried.

The submarines carry the [[Thales Underwater Systems]] Type 2054 composite [[sonar]]. The Type 2054 is a multi-mode, multi-frequency system, which incorporates the 2046, 2043 and 2082 sonars. The Type 2043 is a hull-mounted active/passive search sonar, the Type 2082 a passive intercept and ranging sonar, and the Type 2046 a [[towed array sonar]] operating at very low frequency providing a passive search capability. The fleet is in the process of having the sonars refitted to include open-architecture processing using [[commercial off-the-shelf]] technology. Navigational search capability is provided by a Type 1007 I-band [[navigation radar]].<ref name="Janes"/> They will also be fitted with the new Common Combat System.<ref>{{cite web|url=https://www.gov.uk/government/news/royal-navys-newest-sub-test-fires-torpedo-using-50-million-uk-made-advanced-combat-system|title=Royal Navy's newest sub test fires torpedo using £50 million UK-made advanced Combat System – News stories – GOV.UK|work=gov.uk|access-date=7 August 2016}}</ref> Two [[periscope]]s are carried, a CK51 search model and a CH91 attack model. Both have TV and [[thermal imaging camera]]s in addition to conventional optics.

A specialised [[Submarine Command System]] (SMCS) was originally developed for the ''Vanguard'' boats and was later used on the {{sclass|Trafalgar|submarine|4}}.<ref>See "The Royal Navy Handbook" 2003, Conway Maritime Press, {{ISBN|0-85177-952-2}}</ref>

===Propulsion===
A new [[pressurized water reactor|pressurised water reactor]], the [[Rolls-Royce plc|Rolls-Royce]] [[Rolls-Royce PWR|PWR 2]], was designed for the ''Vanguard'' class. The PWR 2 has double the service life of previous models, and it is estimated that a ''Vanguard''-class submarine could circumnavigate the world 40 times without refuelling. Furthermore, during their long-overhaul refit periods, a 'Core H' reactor is fitted to each of the boats, ensuring that none of the submarines will require further re-fuelling for the rest of their service lives.<ref name="Janes"/> The reactor drives two [[General Electric Company plc|GEC]] [[steam turbine]]s linked to a single shaft [[pump jet]] propulsor, giving the submarines a maximum submerged speed of over {{convert|25|kn|km/h mph}}. Auxiliary power is provided by a pair of 6&nbsp;MW steam-turbine generators supplied by WH Allen, (later known as NEI Allen, Allen Power & Rolls-Royce), and two 905 kWb [[Paxman (engines)|Paxman]] diesel generators for provision of backup power supply.<ref>{{cite web |url=http://www.paxmanhistory.org.uk/paxsubs.htm |title=Paxman Submarine Engines |author=Richard Carr |publisher=Paxman History Pages |date=19 November 2014 |access-date=24 September 2015 |quote=One engine drives a Brush alternator with a rating of 850 kW. The AC output from this provides auxiliary power for the ship's service (hotel) load. The other Valenta is coupled to a Brush generator with a rating of 750 kW, providing DC output for propulsion in the event of failure or non-availability of the main propulsion system (emergency "get you home").}}</ref>

===Nuclear warheads===
[[British nuclear weapons]] are designed and developed by the UK's [[Atomic Weapons Establishment]]. The boats are capable of deploying with a maximum of 192 independently targetable warheads, or [[Multiple independently targetable reentry vehicle|MIRVs]], with immediate readiness to fire. However, as a result of a decision taken by the [[Strategic Defence Review (1998)|1998 Strategic Defence Review]] this was reduced to 48 warheads with a readiness to fire reduced 'to days rather than minutes'. Furthermore, the total number of warheads maintained by the United Kingdom was reduced to approximately 200, with a total of 58 Trident missiles.  The 2010 [[Strategic Defence and Security Review 2010|Strategic Defence and Security Review]] reduced this number further and the submarines will put to sea in future with a reduced total of 40 warheads and a reduced missile load of 8 (from a maximum possible 16). The number of operationally available nuclear warheads is to be reduced 'from fewer than 160 to no more than 120 and the total UK nuclear weapon stockpile will number no more than 180.<ref>{{cite web|url=http://www.direct.gov.uk/prod_consum_dg/groups/dg_digitalassets/@dg/@en/documents/digitalasset/dg_191634.pdf|title=Securing Britain in an Age of Uncertainty: The Strategic Defence and Security Review|date=19 October 2010|publisher=HM Government|access-date=19 October 2010|archive-url=https://web.archive.org/web/20101222022127/http://www.direct.gov.uk/prod_consum_dg/groups/dg_digitalassets/%40dg/%40en/documents/digitalasset/dg_191634.pdf|archive-date=22 December 2010|url-status=dead}}</ref> The warheads, named  Holbrook, use the Mark 4A aeroshell, and have a yield of 100kt. It is thought to be technically similar to the American [[W76]] warhead, with which it shares its aeroshell and some non-nuclear components.<ref name=":2">{{Cite web |last=Mills |first=Claire |date=1 August 2024 |title=Replacing the UK's nuclear deterrent: The warhead programme |url=https://researchbriefings.files.parliament.uk/documents/CBP-9777/CBP-9777.pdf |website=House of Commons Library}}</ref>

On 16 March 2021 Prime Minister Boris Johnson unveiled his government's 10-year plan to boost international trade and deploy soft power around the world with an aspiration of creating a “Global Britain”. In a document called ''[[Integrated Review|Global Britain in a competitive age]]'', this plan raised the cap on the number of nuclear warheads aboard the Royal Navy's Trident submarines from 180 to 260. The document also vowed to maintain a fleet of four nuclear-armed submarines so Britain would always have one at sea.<ref>{{cite news |url=https://www.msn.com/en-us/news/world/boris-johnsons-vision-for-post-brexit-global-britain-starts-with-more-nuclear-weapons/ar-BB1eEtOo?li=BBnbfcL |title=Boris Johnson's vision for post-Brexit 'Global Britain' includes more nuclear weapons |newspaper=The Washington Post |last=Booth |first=William |date=16 March 2021 |access-date=21 June 2021 |via=msn.com}}</ref> Information of number of deployed warheads and missiles would also no longer be provided following the 2021 Integrated Review, under a policy of "deliberate ambiguity".<ref name=":1">{{Cite web |last=Mills |first=Claire |date=2023-05-03 |title=Nuclear weapons at a glance: United Kingdom |url=https://researchbriefings.files.parliament.uk/documents/CBP-9077/CBP-9077.pdf |url-status=live |archive-url=https://web.archive.org/web/20231227005341/https://researchbriefings.files.parliament.uk/documents/CBP-9077/CBP-9077.pdf |archive-date=2023-12-27 |access-date=2024-01-06 |website=House of Commons Library}}</ref>

==Boats of the class==
[[File:HMS Victorious. 08-12-2003 MOD 45143491.jpg|thumb|HMS ''Victorious'' in the Clyde estuary, 2003]]
{| class="wikitable" align="center"
! Name
! Pennant No.
! Builder
! Laid down<ref name="Janes"/>
! Launched<ref name="Janes"/>
! Commissioned<ref name="Janes"/>
! Status
|-
| {{HMS|Vanguard|S28|2}}
| S28
|rowspan=4| [[Vickers Shipbuilding and Engineering]], [[Barrow-in-Furness]]
| 3 September 1986
| 4 March 1992
| 14 August 1993
| In Active Service
|-
| {{HMS|Victorious|S29|2}}
| S29
|3 December 1987
|29 September 1993
|7 January 1995
| In Refit
|-
| {{HMS|Vigilant|S30|2}}
| S30
|16 February 1991
|14 October 1995
|2 November 1996
| In Active Service
|-
| {{HMS|Vengeance|S31|2}}
| S31
|1 February 1993
|19 September 1998
|27 November 1999
| In Active Service
|}

==In fiction==
The 2021 [[BBC]] TV series ''[[Vigil (TV Series)|Vigil]]'' is set on board a fictional ''Vanguard''-class submarine named HMS ''Vigil''. Further boats of the class named HMS ''Virtue'', HMS ''Vanquish'' along with the real HMS ''Vanguard'' are mentioned.<ref>{{cite news |title=BBC One announces brand new thriller Vigil (w/t) |url=https://www.bbc.co.uk/mediacentre/latestnews/2020/vigil |agency=BBC |date=17 January 2020}}</ref>

==See also==
{{Portal|United Kingdom}}
* [[List of submarines of the Royal Navy]]
* [[List of submarine classes of the Royal Navy]]
* [[List of submarine classes in service]]
* [[Royal Navy Submarine Service]]
* [[Future of the Royal Navy]]
* [[Submarine-launched ballistic missile]]
* [[Letters of last resort]]

==References==
{{reflist|30em}}

==Further reading==
*{{Citation |last= Waters |first= Conrad |title= Vanguard Class Submarines – Enter the Twilight Zone |journal= Ships Monthly |pages= 53–57 |date= April 2021}}

==External links==
{{Commons category|Vanguard class submarines}}
* {{cite web |url= https://fas.org/nuke/guide/uk/slbm/vanguard.htm |title= ''Vanguard'' Class Ballistic Missile Submarine |author= Federation of American Scientists |access-date= 18 June 2007}}
* {{cite web |url= http://www.naval-technology.com/projects/vanguard/ |title= Vanguard class |author= Naval technology |access-date= 18 June 2007}}
* Archived at [https://ghostarchive.org/varchive/youtube/20211211/dfpmhAF6_YE Ghostarchive]{{cbignore}} and the [https://web.archive.org/web/20061222131949/http://www.youtube.com/watch?v=dfpmhAF6_YE Wayback Machine]{{cbignore}}: {{cite AV media| title= HMS Vanguard Trident II test-launch |url= https://www.youtube.com/watch?v=dfpmhAF6_YE |publisher= YouTube video |access-date= 18 June 2007}}{{cbignore}}
* {{cite web |url= http://www.military-today.com/navy/vanguard_class.htm|archive-url= https://web.archive.org/web/20070304081328/http://military-today.com/navy/vanguard_class.htm|url-status= usurped|archive-date= 4 March 2007| title=Vanguard class ballistic missile submarine| publisher=Military Today |access-date= 18 June 2007}}
* {{cite news |url= http://news.bbc.co.uk/1/shared/spl/hi/pop_ups/07/uk_on_board_hms_trident_/html/1.stm|work=BBC News |title= In pictures: On board HMS Trident |access-date= 18 June 2007}}
{{Clear}}
{{Vanguard class submarine}}
{{UK submarine classes after 1945}}
{{SSBN classes in service}}
{{Strategic nuclear weapon systems of the United Kingdom}}

{{DEFAULTSORT:Vanguard Class Submarine}}
[[Category:Vanguard-class submarines| ]]
[[Category:Submarine classes of the British Royal Navy]]
[[Category:Nuclear-powered submarines]]
[[Category:Ballistic missile submarines]]
[[Category:Trident (UK nuclear programme)]]