HMS Vengeance (S31)
HMS Vengeance returning to HMNB Clyde in 2007
|Laid down:||1 February 1993|
|Launched:||19 September 1998|
|Commissioned:||27 November 1999|
|In service:||12 February 2001|
|Motto:||Safe by my strength|
|Class and type:||Vanguard-class submarine|
|Displacement:||15,900 tonnes, submerged|
|Length:||149.9 m (491 ft 10 in)|
|Beam:||12.8 m (42 ft 0 in)|
|Draught:||12 m (39 ft 4 in)|
|Speed:||In excess of 25 knots (46 km/h; 29 mph), submerged|
|Range:||Only limited by food and maintenance requirements.|
|Sensors and |
|Electronic warfare |
Before she was commissioned, the British Government stated that once the Vanguard submarines became fully operational, they would only carry 200 warheads.
Vengeance carries unopened "last instructions" (letters of last resort) of the current British Prime Minister that are to be used in the event of a national catastrophe or a nuclear strike; this letter is identical to the letters carried on board the other three submarines of the Vanguard class. 
On 31 March 2011, while on a training exercise Vengeance suffered a blockage in her propulsor causing a reduction in propulsion. The boat returned to Faslane naval base on the surface under her own power. According to the MOD the problems were not nuclear related.
In 2012, Vengeance started a 40 month refit at HMNB Devonport near Plymouth which refueled her reactor and renewed her machinery and electronics. During that period her sister ship Vigilant took her place in the patrol rotations. She sailed from Devonport on 4 December 2015, her place in refit being taken by Vanguard. Vengeance then went through trials from January 2016 to June 2016 and fired an unarmed D5 missile during her Demonstration and Shakedown Operation (DASO) which allowed her to return to the fleet. Whilst the firing of the missile was a success, the missile itself suffered a failure during flight and the test was terminated. 
- The Royal Scots Dragoon Guards (Carabiniers and Greys)
- Worshipful Company of Salters
- Bury St Edmunds
- Displacement: 16,000 tons submerged
- Propulsion: Rolls-Royce PWR2 reactor, two GEC turbines, single shaft, pump jet propulsor
- Electrical Power: two Paxman diesel generators, two WH Allen turbogenerators
- Speed: 25 knots (46 km/h; 29 mph) submerged
- Complement: 14 officers, 121 men
- Strategic Armament: 16 Lockheed Trident II D5 ballistic missiles
- Defensive Armament: four 533 mm (21-inch) torpedo tubes, Spearfish torpedoes
- List of submarines of the Royal Navy
- List of submarine classes of the Royal Navy
- Nuclear weapons and the United Kingdom
- Royal Navy Submarine Service
- Submarine-launched ballistic missile
- Trident nuclear programme
- Jane's Fighting Ships, 2004–2005. Jane's Information Group Limited. p. 794. ISBN 0-7106-2623-1.
- "Vanguard class submarine". Royal Navy.
- "HMS Vengeance nuclear sub returns home after power loss". BBC News. 3 April 2011.
- "The Current British Arsenal". The Nuclear Weapon Archive - A Guide to Nuclear Weapons. 30 April 2001. Retrieved 23 February 2007.
- Hennessy, Peter (2007). Cabinets and the Bomb. Oxford: Oxford University Press. ISBN 978-0-19-726422-5. Reviewed on "Start the Week". BBC Radio 4. 5 November 2007.
- Edwards, Rob (3 April 2011). "Trident sub crippled in accident". The Herald. Glasgow. Archived from the original on 12 August 2011.
- "HMS Vengeance: 350m sub refit 'to secure 2,000 jobs'". BBC News. 26 March 2012. Retrieved 24 September 2015.
- "Farewell Vengeance, hello Vigilant, as submarines trade places in £600m revamp". Royal Navy. 1 March 2012. Archived from the original on 11 March 2013.
- Crowther, Daryl (4 December 2015). "Nuke sub HMS Vengeance leaves Devonport". Combat & Survival. Retrieved 13 March 2016.
- "No 10 covered up Trident missile fiasco". The Sunday Times. London. 22 January 2017. Retrieved 7 January 2019.
- Rosamund, Jon (25 January 2017). "Royal Navy Trident Missile 'Malfunction' Prompts Claims of U.K. Government Cover-Up". USNI News. Retrieved 7 January 2019.