HMS Trenchant (S91)

HMS Trenchant is a Trafalgar-class nuclear-powered fleet submarine of the Royal Navy built by Vickers Shipbuilding, Barrow-in-Furness. Trenchant is in service and is based at HMNB Devonport. She is the third vessel and the second submarine of the Royal Navy to be named for the characteristic of vigour and incisiveness.

HMS Trenchant (2017)
United Kingdom
Name: HMS Trenchant
Ordered: 22 March 1983
Builder: Vickers Shipbuilding, Barrow-in-Furness
Laid down: 28 October 1985
Launched: 3 November 1986
Commissioned: 14 January 1989
Homeport: HMNB Devonport, Plymouth
Fate: in active service
General characteristics
Class and type: Trafalgar-class submarine
  • Surfaced: 4,500 to 4,800 t (4,700 long tons; 5,300 short tons)[1]
  • Submerged: 5,200 to 5,300 t (5,200 long tons; 5,800 short tons)[1]
Length: 85.4 m (280 ft)[1]
Beam: 9.8 m (32 ft)[1]
Draught: 9.5 m (31 ft)[1]
  • 1 × Rolls Royce PWR1 nuclear reactor
  • 2 × GEC steam turbines
  • 2 × WH Allen turbo generators; 3.2 MW
  • 2 × Paxman diesel alternators 2,800 shp (2.1 MW)
  • 1 × pump jet propulsor
  • 1 × motor for emergency drive
  • 1 × auxiliary retractable prop
Speed: Over 30 knots (56 km/h), submerged[1]
Range: Unlimited[1]
Complement: 130[1]
Electronic warfare
& decoys:
  • 2 × SSE Mk8 launchers for Type 2066 and Type 2071 torpedo decoys
  • RESM Racal UAP passive intercept
  • CESM Outfit CXA
  • SAWCS decoys carried from 2002
  • 5 × 21-inch (533 mm) torpedo tubes with stowage for up to 30 weapons:

The submarine was ordered on 22 March 1983. She was laid down by Vickers Shipbuilding on 28 October 1985, and was launched on 3 November 1986 in the presence of Vice Admiral Sir Arthur Hezlet, who had commanded the World War II T-class submarine Trenchant.[2] She was commissioned into the Royal Navy on 14 January 1989.[3]

Trenchant was scheduled to be decommissioned in 2019 but has yet to be.[4]

Operational history


On 22 November 1990, the nets of the fishing vessel Antares were snagged by Trenchant in the Bute Sound in Scotland. At the time the submarine was conducting a 'Perisher' Submarine Command Course exercise in company with the frigate HMS Charybdis. Antares was pulled under with the loss of all four members of the crew.[5][6][7]

In July 1997, the submarine ran aground off the western coast of Australia.[8] While approaching Fremantle, Western Australia, the submarine remained at a depth of 200 metres (660 ft) and grounded when she made contact with the continental shelf, coming to rest on a sloping patch of seafloor.[8] Trenchant was able to free herself, and an inspection by divers reported no significant damage.[8]

Trenchant tested the non-hull-penetrating optronic mast in 1998. She also trialled a camouflage paint scheme comprising jagged shapes of various colours, including pale blue.

2000-present day

On 21 June 2007, the submarine became the first Royal Navy vessel to fire the new Block IV Tomahawk cruise missile in a live-firing trial in the Gulf of Mexico off the United States coast.[9]

In late 2009, Trenchant entered the Devonport submarine refit complex to undertake a 2-year refit and upgrade programme. Upon completion of the programme, the submarine underwent a rededication service on 6 June 2011 to welcome the boat back to active service.[10]

On 22 May 2013, Trenchant completed the longest patrol ever carried out by a Royal Navy SSN. The patrol lasted 335 days (11 months) during which the submarine sailed 38,800nm.[11] During this time the vessel has visited six different ports: Fujairah, UAE; the British Indian Ocean Territory – Diego Garcia; the Kingdom of Bahrain; Aqaba, Jordan; Souda Bay, Crete; and Gibraltar.[12][13]

Following a maintenance period involving a weapon and sensors upgrade, Trenchant returned to service in August 2016.[14]

In March 2018, Trenchant, along with American submarines USS Connecticut and USS Hartford, participated in ICEX 2018, surfacing through the Arctic ice. This was the first time a Royal Navy submarine participated in ICEX since 2007.[15][16][17]


Trenchant is affiliated with the following military and civilian organisations, bodies & individuals:[10]


  1. Bush, Steve (2014). British Warships and Auxiliaries. Maritime Books. p. 12. ISBN 1904459552.
  2. "HMS Trenchant (S91) - Royal Navy". Retrieved 7 August 2016.
  3. Jane's Fighting Ships, 2004-2005. Jane's Information Group Limited. p. 796. ISBN 0-7106-2623-1.
  4. Hansard HL Deb 14 March 2005 vol 670 c116WA quoted in House of Commons Defence Committee - Fourth Report, 12 Dec 2006
  5. "Collision between pelagic trawler Antares and trafalgar-class submarine HMS Trenchant with loss of 4 lives Marine Accident Investigation Branch report - GOV.UK". Retrieved 7 August 2016.
  6. "Kintyre". Archived from the original on 29 January 2008. Retrieved 12 December 2007.
  7. Cusick, James (10 July 1992). "Submarine crew blamed for sinking of Antares". The Independent. London.
  8. Stewart, Cameron (8 April 2009). "Brits' nuclear sub accident surfaces". The Australian. p. 6. Retrieved 10 April 2009.
  10. "Navy News - Reporting from the Fleet". Retrieved 7 August 2016.
  11. "UK: HMS Trenchant Comes Home from the Longest Patrol Ever". Retrieved 7 August 2016.
  12. "Trenchant completes record-breaking mission- Royal Navy". Retrieved 7 August 2016.
  13. "Royal Navy submarine returns from longest patrol". Ministry of Defence. 24 May 2013. Retrieved 3 October 2017.
  14. George Allison (22 August 2016). "Nuclear submarine HMS Trenchant rejoins the fleet". UK Defence Journal. Retrieved 16 February 2017.
  15. Royal Navy (15 March 2018). "Royal Navy submarine breaks through Arctic ice for major exercise". Royal Navy. Retrieved 29 March 2018.
  16. US Navy (29 January 2018). "ICEX 2018 Welcome Letter" (PDF). US Navy. Retrieved 29 March 2018.
  17. "Nuclear sub breaks ice at North Pole". BBC News. Retrieved 24 April 2018.


  • Submarines, War Beneath The Waves, From 1776 To The Present Day, by Robert Hutchinson

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.