Military Wiki
HMCS Corner Brook (SSK 878)
HMCS Corner Brook (SSK 878)
HMCS Corner Brook entering St John's Harbour on the east end of Newfoundland
Career (United Kingdom)
Name: HMS Ursula
Builder: Cammell Laird, Birkenhead
Laid down: 10 January 1989
Launched: 22 February 1991
Commissioned: 8 May 1992
Decommissioned: 1994
Fate: Transferred to Canada
Career (Canada)
Name: HMCS Corner Brook
Acquired: 1998
Commissioned: March 2003
Status: in active service, as of 2022 (in dock for repairs/awaiting damage assessment)
General characteristics
Class & type: Upholder/Victoria-class submarine
Type: Fleet submarines / long range hunter-killer submarines
Displacement: 2,185 long tons (2,220 t) surfaced
2,400 long tons (2,439 t) submerged
Length: 70.26 m (230 ft 6 in)
Beam: 7.6 m (24 ft 11 in)
Draught: 5.5 m (18 ft 1 in)
Propulsion: Diesel-electric (37 MW)
2 Paxman Valenta 16 RPA diesel generators, 4,070 hp (3,035 kW)
2 GEC 5,000 kW motor-generators
Speed: 12 knots (22 km/h; 14 mph) surfaced
20 kn (23 mph; 37 km/h)+ submerged
Range: 10,000 nautical miles (18,500 km) at 12 knots (22 km/h)
Test depth: 200 m (660 ft)
Complement: 53 officers and crew
Armament: • 6 × 21 in (530 mm) torpedo tubes
• 18 × Mark 48 torpedoes

HMCS Corner Brook (SSK 878) is a long-range hunter-killer submarine (SSK) of the Royal Canadian Navy. She is the former Royal Navy Upholder class submarine HMS Ursula (S42), purchased from the British at the end of the Cold War. She is the third boat of the Victoria class and is named after the city of Corner Brook, Newfoundland.


Corner Brook's displacement is approximately 2,200 tons surfaced and 2,400 tons submerged. Covered in anechoic tiles to reduce her detection by active sonar, the submarine is 70.3 meters long, 7.6 meters across the beam and has a deep diving depth in excess of 200 meters. The main hull is constructed of high tensile steel sections stiffened by circular internal frames. Equipment located outside the main hull is covered by the casing, which also gives the crew a safe walkway when the submarine is surfaced. The fin, which helps support the masts, serves as a kind of keel and provides a raised conning position.

Corner Brook has six torpedo tubes and can carry up to eighteen Mark 48 Mod 4 heavyweight torpedoes for use against surface and sub-surface targets.

Corner Brook's sonar sets allow her to locate and track ships and other submarines passively: that is, without transmitting on active sonar and thus giving away her location. She is fitted with radar for general navigation, attack and search periscopes (incorporating video recording and thermal imaging), and an electronic support measures suite.

The boat has two diesel generators, each capable of producing up to 1,410 kilowatts, and one main motor. The generators are used to charge two main batteries, each consisting of 240 cells. These batteries are used to power the submarine, which can reach a submerged speed of up to 20 knots (37 km/h).


The submarine was laid down as HMS Ursula at Cammell Laird's Birkenhead yard on 10 January 1989.[1] She was launched on 28 February 1991 and commissioned into the Royal Navy on 8 May 1992.[1]

Operational history

Royal Navy

Ursula was decommissioned on 16 October 1994.[1]


Looking to discontinue the operation of diesel-electric boats, the British government offered to sell Ursula and her sister submarines to Canada in 1993.[2] The offer was accepted in 1998.[2] The four boats were leased to the Canadians for US$427 million (plus US$98 million for upgrades and alteration to Canadian standards), with the lease to run for eight years; the submarines would then be sold for £1.[1]

Problems were discovered with the piping welds on all four submarines, which delayed the reactivation of Ursula and her three sisters.[1] Ursula was handed over to the Canadian Forces on 21 February 2003, and commissioned as HMCS Corner Brook on 26 June 2003.[1]

Royal Canadian Navy

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The factual accuracy of this article may be compromised due to out-of-date information

During a refit in 2006, elevated levels of lead were detected aboard the submarine; they were believed to come from the lead-brick ballast blocks used aboard Corner Brook.[3]

The submarine participated in NATO exercise 'Noble Mariner' during May 2007.[4] During the exercise, which occurred in the Baltic region, Corner Brook successfully closed with the aircraft carrier HMS Illustrious without being detected.[4] The submarine returned to Canada, and in August, she participated in Operation Nanook, a sovereignty exercise held in and around Iqaluit and the Baffin Island coastal and the Hudson Strait areas.[4]

Between October 2006 and January 2008, Corner Brook was active for only 81 days.[5]

In February 2008, Corner Brook departed from Halifax during a snowstorm for a three-month deployment to the Caribbean Sea.[6] As part of the deployment, the submarine operated with the United States Joint Interagency Task Force South, which attempts to counter drug trafficking, people smuggling and piracy in the region.[6] Corner Brook returned to Halifax in May.[6]

In January 2009, Corner Brook was the 'target' for submarine detection exercises performed by HMCS Halifax and HMCS Montreal[7] This was followed by a four-week, multi-ship training exercise in the North Atlantic during February and March,[8] then participation in the UNITAS multinational exercise off Florida during late April and early May.[9] During August, the submarine was involved in Operation Nanook 2009.[10][11]

In June 2011 the submarine ran aground during manoeuvres off Vancouver Island. Two submariners were slightly injured.[12]

After the grounding incident civilian and military submariners began pre-maintenance work on the submarine, in the expectation of an extended maintenance program. To quote a reference: "How long that process will take and how much it will cost isn't {yet] known since the amount of work varies vessel to vessel. Work on each sub must be individually negotiated within a larger 15-year contract of up to $1.5 billion that the Department of National Defence awarded to the Canadian Submarine Management Group in 2008. Victoria Shipyards is a subcontractor on the project." [13]

In February 2012, post-collision photos of the dry-docked submarine were published, showing extensive damage to the bow; the media also cited unofficial sources, saying the pressure hull may be damaged beyond repair.[14]


External links

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