User:Llammakey/Canadian ship articles II

Canadian ship articles I References Canadian ship articles III

Tribal class

The Tribal class were ordered by the Canadian Naval Staff's intent to build a stronger, permanent force. The Tribals were designed to fight heavily armed destroyers of other navies, such as the Japanese Fubuki class. Canada chose the design based on its armament, with the size and power of the Tribal class allowing them to act more like small cruisers than as fleet destroyers. The Naval Staff intended to order the construction of a flotilla of Tribals, with two under construction every year. However, due to war demands, British yards could not accommodate such a request. Therefore, it was decided that Canadian shipyards would construct the second batch of Tribals. They were ordered with modified ventilation and heating systems for North Atlantic winter service. Design modifications were made after deficiencies were noted in Iroquois, the lead ship of the Canadian Tribals. Canadian Tribals were a foot longer than their British counterparts and carried an auxiliary boiler for heating and additional power requirements.

During construction delays soon began due to a shortage of skilled labour and engineering personnel. Furthermore, on the first batch, Micmac and Nootka, there was a shortage of high-quality steel in Canada required in the construction of destroyers. The steel was imported from the United States. By the time the second batch of Canadian-built Tribals, Cayuga and the second Athabaskan, began construction, Canada was capable of providing the steel.

The ship was 335 feet 6 inches (102.3 m) long between perpendiculars and 377 feet (114.9 m) long overall with a beam of 36 feet 6 inches (11.1 m) and a draught of 13 feet (4.0 m). As built, the destroyer had a standard displacement of 1,927 long tons (1,958 t) and 2,745 long tons (2,789 t) at deep load. Nootka had a complement of 14 officers and 245 ratings. The destroyer was propelled by two shafts driven by two Parsons single-reduction geared turbines powered by steam created by three Admiralty-type three-drum boilers. Each boiler was housed in a separate compartment and were rated at 300 lbf/in² (2,100 kPa; 21 kgf/cm²). This created 44,000 shaft horsepower (33,000 kW) and gave the ship a maximum speed of 36.5 knots (67.6 km/h; 42.0 mph). The destroyers could carry 505–516 long tons (513–524 t) of fuel oil. Tribals had poor freeboard and were considered "wet" ships. They had a range of 5,700 nautical miles (10,600 km; 6,600 mi) at 15 knots (28 km/h; 17 mph).

As built, Nootka was fitted with six quick firing 4.7-inch (119 mm) Mk XII guns placed in three twin turrets, designated 'A', 'B' and 'Y' from bow to stern. The turrets were placed on 40° mountings with open-backed shields. The ship also had one twin turret of QF 4-inch (102 mm) Mk XVI guns in the 'X' position. The mounts were powered by turbo generators and turbo-hydraulic units. For secondary anti-aircraft armament, the destroyer was equipped with four single-mounted 2-pounder "pom-pom" guns and six Oerlikon 20 mm cannon. The vessel was also fitted with four 21-inch (533 mm) torpedo tubes in one quad mounting, situated behind the second funnel for Mk IX torpedoes. Along the stern of the ships were racks for depth charges positioned along the centreline, holding three depth charges at a time and space for nine reloads. A depth charge thrower was set high on each side of the superstructure ahead of the tripod main mast.

The ship was equipped Type 291 radar for air search, Type 293 radar for target indication and Type 285 for 4.7-inch gun control and a DCT controller, utilizing a Fuze Keeping Clock, for the 4-inch guns (working with the Type 285 radar). The radar was carried on a lattice mast and the HF/DF was situated on a pole aft.

Flower class

Design and description

1939–1940 and 1940–1941 Programmes

Main article: Flower-class corvette

Flower-class corvettes like ---- serving with the Royal Canadian Navy during the Second World War were different from earlier and more traditional sail-driven corvettes. The Flower-class corvettes originated from a need that arose in 1938 to expand the Royal Navy following the Munich Crisis. A design request went out for a small escort for coastal convoys. Based on a traditional whaler-type design, the initial Canadian ships of the Flower class had a standard displacement of 950 long tons (970 t). They were 205 feet 1 inch (62.51 m) long overall with a beam of 33 feet 1 inch (10.08 m) and a maximum draught of 13 feet 5 inches (4.09 m). The initial 1939–1940 corvettes were powered by a four-cylinder vertical triple expansion engine powered by steam from two Scotch boilers turning one three-bladed propeller rated at 2,800 indicated horsepower (2,100 kW). The Scotch boilers were replaced with water-tube boilers in later 1939–1940 and 1940–1941 Programme ships. The corvettes had a maximum speed of 16 knots (30 km/h; 18 mph). This gave them a range of 3,450 nautical miles (6,390 km; 3,970 mi) at 12 knots (22 km/h; 14 mph). The vessels were extremely wet.

The Canadian Flower-class vessels were initially armed with a Mk IX BL 4-inch (102 mm) gun forward on a CP 1 mounting and carried 100 rounds per gun. The corvettes were also armed with a QF Vickers 2-pounder (40 mm, 1.6 in) gun on a bandstand aft, two single-mounted .303 Vickers machine guns or Browning 0.5-calibre machine guns for anti-aircraft defence and two twin-mounted .303 Lewis machine guns, usually sited on bridge wings. For anti-submarine warfare, they mounted two depth charge throwers and initially carried 25 depth charges. The corvettes were designed with a Type 123 ASDIC sonar set installed. The Flower-class ships had a complement of 47 officers and ratings. The Royal Canadian Navy initially ordered 54 corvettes in 1940 and these were fitted with Mark II Oropesa minesweeping gear used for destroying contact mines. Part of the depth charge rails were made portable so the minesweeping gear could be utilised.

Modifications

In Canadian service the vessels were altered due to experience with the design's deficiencies. The galley was moved further back in the ship and the mess and sleeping quarters combined. A direction-finding set was installed and enlarged bilge keels were installed to reduce rolling. After the first 35–40 corvettes had been constructed, the foremast was shifted aft of the bridge and the mainmast was eliminated. The compass house was moved further aft and the open-type bridge was situated in front of it. The ASDIC hut was moved in front and to a lower position on the bridge. The Type 271 radar was placed aft. The minesweeping gear, a feature of the first 54 corvettes, was removed. Most Canadian Flower-class corvettes had their forecastles extended which improved crew accommodation and seakeeping. Furthermore, the sheer and flare of the bow was increased, which led to an enlarged bridge. This allowed for the installation of Oerlikon 20 mm (0.8 in) cannon, replacing the Browning and Vickers machine guns. Some of the corvettes were rearmed with Hedgehog anti-submarine mortars. The complements of the ships grew throughout the war rising from the initial 47 to as many as 104.

Construction and career

The vessel was ordered as part of the 1939–1940 Progamme in January 1940, and laid down on 29 April 1940 by Burrard Dry Dock Co. Ltd. in North Vancouver, British Columbia. Corvettes commissioned by the Royal Canadian Navy during the Second World War were not named after flowers, as the class name might suggest, but after communities for the most part, to better represent the people who took part in building them. This idea was put forth by Admiral Percy W. Nelles. Sponsors were commonly associated with the community for which the ship was named. Agassiz, named for the town in British Columbia, was launched on 15 August 1940 and commissioned on 23 January 1941 in Vancouver, British Columbia.

HMCS Warrior

Description

Warrior was a Colossus-class light aircraft carrier that was 630 feet 0 inches (192.0 m) long at perpendiculars and 695 feet 0 inches (211.8 m) overall with a beam at the waterline of 80 feet 0 inches (24.4 m) and an overall width of 112 feet 6 inches (34.3 m). The ship had a mean draught of 23 feet 3 inches (7.1 m). Warrior had a standard displacement of 13,350 long tons (13,560 t) when built and a full load displacement of 18,300 long tons (18,600 t). The aircraft carrier had a flight deck 690 feet 0 inches (210.3 m) long that was 80 feet 0 inches (24.4 m) wide and was 39 feet 0 inches (11.9 m) above the water. The flight deck tapered to 45 feet (14 m) at the bow. For takeoffs, the flight deck was equipped with one BH 3 aircraft catapult capable of launching 16,000-pound (7,257 kg) aircraft at 66 knots (122 km/h). For landings, the ship was fitted with 10 arrestor wires capable of stopping a 15,000-pound (6,804 kg) aircraft, with two safety barriers rated at stopping a 15,000-pound aircraft at 40 knots (74 km/h) Warrior had two aircraft elevators located along the centreline of the ship that were 45 by 34 feet (13.7 by 10.4 m) and could handle aircraft up to 15,000 pounds on a 36-second cycle. The aircraft hangar was 275 by 52 feet (83.8 by 15.8 m) with a further 57 by 52 feet (17.4 by 15.8 m) section beyond the aft elevator, all with a clearance of 17 feet 6 inches (5.3 m). The hangar was divided into four sections by asbestos fire curtains. The hangar was fully enclosed and could only be entered by air locks and the lifts, due to the hazardous nature of aviation fuel and oil vapours. The vessel had stowage for 98,600 imperial gallons (448,244 L; 118,414 US gal) of aviation fuel.

The ship was powered by steam created by four Admiralty 3-drum type boilers driving two Parsons geared turbines, each turning one shaft. The machinery was separated into to two spaces, each containing two boilers and one turbine, separated by 24-foot (7.3 m) spaces containing aviation fuel. The spaces were situated en echelon within the ship to prevent a single disabling torpedo strike. The engines were rated at 42,000 shaft horsepower (31,319 kW) and the vessel had a capacity for 3,196 long tons (3,247 t) of fuel oil, with an endurance of 8,300 nautical miles (15,372 km) at 20 knots (37 km/h). The ship's maximum speed was 25 knots (46 km/h). There was no armour aboard the vessel save for mantlets around the torpedo storage area. There were no longitudinal bulkheads, but the transverse bulkheads were designed to allow the ship to survive two complete sections of the ship being flooded.

Warrior was designed to handle up to 42 aircraft. The aircraft carrier carried a wide range of ordnance for their aircraft from torpedoes, depth charges, bombs, 20 mm cannon ammunition and flares. For anti-aircraft defence, the aircraft carrier was initially armed with four twin-mounted and twenty single-mounted 40 mm Bofors guns. The original radar installation included the Type 79 and Type 281 long-range air search radars, the Type 293 and Type 277 fighter direction radar and the "YE" aircraft homing beacon. The ship had a maximum ship's company of 1,300, which was reduced in peace time.

FELEX

Planning for FELEX began in 2002. However it was not until November 2008 that a contract was awarded to Lockheed Martin Canada as prime contractor. The cost of the contract was $2 billion CAN.

The FELEX upgrade

While planning, preparation and co-ordination of the HCM/ FELEX project began back in 2002, it was not until November 2008 that Lockheed Martin Canada Mission Systems and Training was brought under contract as prime contractor and Combat System Integration (CSI) and in-service support agent. Under the C$2 billion CSI contract, Lockheed Martin Canada is taking responsibility for the development, integration and test of a new CMS, together with the procurement integration of new radars, ESM, Identification Friend or Foe (IFF) equipment, and a multi-link data processor. The company is additionally responsible for redesign of ship compartments and structures, modifications to the operations room, and the provision of a suite of simulation/ training systems, and is also integrating other sensors and weapons acquired under prior standalone programmes.

Upgraded combat system At the core of the upgraded combat system is the upgraded CMS330 command and control system, which introduces open architecture and functionality from Saab’s 9LV Mk 4 CMS line.

The SPS-49 2D long range air search radar is replaced by the Thales Nederland SMART-S Mk 2 E/F-band 3D surveillance radar, while the two legacy STIR 1.8 firecontrol radars are replaced by a pair of Saab Ceros 200 re-control radars. The existing Sea Giraffe 150HC is also being enhanced by Saab to improve performance in high clutter environments.

Other key equipments being introduced under the scope of the HCM/FELEX programme comprise a Telephonics IFF Mode 5/S interrogator, the Elisra NS9003A-V2HC ESM system (replacing the SLQ-501 CANEWS suite), an IBM multi-link (Link 11, Link 16 and Link 22 enabled) datalink processing system, and two Raytheon Anschütz Pathfinder Mk II navigation radars.

Lockheed Martin Canada is also responsible for integrating other equipments (acquired separately by the Canadian government and supplied to the programme as government-furnished materiel) into the upgraded combat system.

For example, a tailored variant of Rheinmetall’s Multi-Ammunition So kill System (MASS), known as MASS_DUERAS, has been procured to replace the obsolete Plessey Shield decoy system.

BAE Systems Bofors is upgrading existing 57mm Mk 2 guns to Mk 3 standard.

New 3P ‘smart’ pre-fragmented programmable ammunition is being introduced commensurate with the Mk 3 upgrade. Other weapons integrated as part of the HCM/FELEX upgrade include the Harpoon Block II surface-to- surface guided weapon, the Phalanx Block 1B close-in weapon system, and the Evolved SeaSparrow Missile point defence missile system.

HMCS Ville de Quebec completed her modernisation in late 2015, but has yet to return to operations.

In April 2016, HMCS Regina, the fifth and final frigate on the west coast to complete its modernisation by Seaspan’s Victoria Shipyard, was returned to the RCN to complete sea trials.

HMCS Toronto, the seventh and final east coast frigate, and the last of the 12 ships to go through the HCM/FELEX modernisation, is due to complete its refit at Irving Shipbuilding’s Halifax Shipyard in the third quarter of this year.

Following acceptance of Toronto, corresponding sea trials and project close-out activities are expected to be completed by January 2018.

Bluethroat

Bluethroat, constructed as a mine and loop layer, had a standard displacement of 785 long tons (798 t) and 870 long tons (880 t) at full load. The vessel measured 157 feet (47.9 m) long overall and 150.7 feet (45.9 m) between perpendiculars, a beam of 33 feet (10.1 m) with a draught of 10 feet (3.0 m). The ship was powered by a diesel engine driving two shafts rated at 1,200 brake horsepower (890 kW). The ship had a maximum speed of 13 knots (24 km/h; 15 mph).

The ship was authorised as part of the 1951 Programme during the Korean War. The ship was laid down by George T. Davie & Sons Ltd. at their yard in Lauzon, Quebec on 31 October 1952. Bluethroat was launched on 15 September 1955 and completed on 28 November. The ship was designated a harbour mineplanter upon commissioning and in 1957, re-designated a controlled minelayer. In 1959, the ship was re-designated a cable layer. Bluethroat took part in the NATO naval exercise Sweep Clear V off the coast of Shelburne, Nova Scotia in October 1960. In 1964, the ship was re-designated a research vessel.

Norton-class tug

The four Norton-class tugboats constructed for the Royal Canadian Navy were of a modified design. They had a displacement of 462 long tons (469 t), were 104 feet (31.7 m) long between perpendiculars and 111+3⁄4 feet (34.1 m) overall with a beam of 28 feet (8.5 m) and a draught of 11 feet (3.4 m). They were powered by Dominion Sulzer diesel engines rated at 1,000 brake horsepower (750 kW) with a maximum speed of 11 knots (20 km/h; 13 mph). They had a complement of 17. They were rated as large harbour tugs.

Clifton was launched on 31 July 1944. Beaverton was sunk in a collision in 1947 at Montreal, Quebec.

Saint-class tug

The Saint class were authorised in the 1951 Programme. Ocean-going tugboats, they had a full load displacement of 840 long tons (850 t). They had a length overall of 46.2 metres (151 ft 7 in), a beam of 10 metres (32 ft 10 in) and a draught of 5.2 metres (17 ft 1 in). They were powered by a diesel engine driving one shaft rated at 1,920 brake horsepower (1,430 kW). They had a maximum speed of 14 knots (26 km/h; 16 mph). The Saint class had a complement of 21. They were armed with two Bofors 40 mm (1.57 in) gun for anti-aircraft defence.

The three tugboats were constructed by St. John Dry Dock Company. Saint Anthony was commissioned on 22 February 1957. Saint Charles was commissioned on 7 June 1957.

Saint class
Name	Hull number	Builder	Laid down	Launched	Completed	Fate
Saint Anthony	ATA 531	St John Dry Dock Co.	15 July 1954	2 November 1955	22 February 1957
Saint Charles	ATA 533		28 April 1954	10 July 1956	7 June 1957
Saint John	ATA 535		1 December 1953	14 May 1956	23 November 1956

Wasaga

In January 1943, the Royal Navy destroyer HMS Caldwell was being towed to Boston to have her propellers installed by the tugboat Foundation Franklin. During transit, the ships passed into a storm, where under strain, Foundation Franklin's towing winch broke and was unable to resume towing. Caldwell was cast adrift on the Atlantic, while attempts to make makeshift towing lines were prepared. Wasaga, escorting the two vessels, aided in getting the destroyer back under tow, this time by the Canadian destroyer HMCS Columbia, which had come to aid the stricken Caldwell. The minesweeper then escorted the two destroyers to Halifax.

Composition of the Fleet in 1961

Compostion of fleet in 1961

-Atlantic Command-

• Bonaventure
• First Escort
  • Algonquin
  • Huron
  • Haida
  • Nootka
  • Iroquois
• Third Escort
  • Crescent
  • Micmac
  • Sioux
  • Cayuga
  • Athabaskan
• Fifth Escort
  • Gatineau
  • Restigouche
  • Kootenay
  • St. Croix
  • Terra Nova
  • Chaudière
  • Columbia
• Seventh Escort
  • Fort Erie
  • New Waterford
  • Lanark
  • Outremont
  • Victoriaville
  • Inch Arran
• Ninth Escort
  • Cap de la Madeleine
  • Lauzon
  • La Hulloise
  • Swansea
  • Buckingham
• First Minesweeping
  • Chaleur
  • Chignecto
  • Quinte
  • Thunder
  • Resolute
  • Fundy
• Auxiliary
  • Cape Scott
  • Crusader
  • Granby
  • Porte Saint Jean
  • Loon
  • Mallard
  • Cormorant
• Air Squadrons
  • VF-870
  • VS-880
  • VU-32
  • HS-50
  • HU-21
  • VX-10

-Pacific Command-

• Second Escort
  • Ottawa
  • Saguenay
  • St. Laurent
  • Margaree
  • Fraser
  • Skeena
  • Assiniboine
• Fourth Escort
  • Jonquiere
  • Sussexvale
  • Beacon Hill
  • Antigonish
  • Ste. Therese
  • New Glasgow
  • Stettler
• Second Minesweeping
  • Fortune
  • James Bay
  • Miramachi
  • Cowichan
• Auxiliary
  • Cape Breton
  • Grilse
  • Oriole
• Air Squadrons
  • VU-32

Escort Squadrons

1st MS Squadron

The First Canadian Minesweeping Squadron was constituted in December 1953. Gaspe and Chignecto were the initial members. They were joined by Cowichan and Thunder. The squadron was commanded by Lt. Cmdr. Bruce Carnall, commanding officer of Gaspe. Trinity and Ungava joined the squadron upon commissioning on 16 June and 4 June 1954 respectively. Resolute joined the squadron upon commissioning on 16 September 1954. The squadron, comprising, Gaspe, Trinity, Ungava and Quinte, sailed to the Caribbean Sea in April 1955 for a training cruise, making several port visits.

In May 1956, the First Canadian Minesweeping Squadron deployed as part of the NATO minesweeping exercise Minex Sweep Clear One in the western Atlantic. Gaspe, Trinity and Resolute. Ungava did not partake in the exercise, having been detached for duties for naval commanders in Newfoundland.

2nd MS Squadron

Comox was flagship of the Second Canadian Minesweeping Squadron of Pacific Command. The Second Canadian Minesweeping Squadron was formed in May 1954 at Esquimalt with Comox and James Bay as the first two vessels of the unit. Fortune later joined the unit. In November 1955, the Second Canadian Minesweeping Squadron was among the Canadian units that took part in one of the largest naval exercises since the Second World War off the coast of California.

1st Escort Squadron

The First Canadian Escort Squadron came into being on 10 November 1953 as part of Atlantic Command. Algonquin was the flagship and the unit was initially commanded by Patrick F.X. Russell. The unit was initially composed of Algonquin, Lauzon, Prestonian and Toronto. Penetang joined the First Canadian Escort Squadron upon commissioning on 1 June 1954.

2nd Escort Squadron

The Second Canadian Escort Squadron was established on 1 January 1955 under Pacific Command. It initially comprised the destroyer escorts Cayuga, Crescent and Athabaskan and the frigates Jonquiere, Stettler, New Glasgow, Ste. Therese and Sussexvale. The initial commanding officer of the group was Commander Henry H. Davidson, captain of Cayuga. In November 1955, the Second Canadian Escort Squadron was among the Canadian units that took part in one of the largest naval exercises since the Second World War off the coast of California. In June 1956, the squadron was composed of the destroyers Cayuga, Athabaskan and Sioux and the frigates Ste. Therese, Stettler and Sussexvale. The squadron departed on a two-month training cruise off Hawaii and California, returning to Esquimalt on 10 August.

3rd Escort Squadron

The Third Canadian Escort Squadron comprised the frigates Lanark, Fort Erie and Lauzon. The Third Squadron performed a training cruise to Europe in July 1956, visiting the United Kingdom and Belgium.

2nd Reserve Squadron

The Second Canadian Reserve Squadron was established on 5 January 1955 under Pacific Command. It initially comprised the coastal escorts Brockville, Digby and Cordova. Employed for training purposes, the group was initially commanded by Lieutenant Commander E.S. Cassels of Brockville.

11th Escort Squadron

The 11th Canadian Escort Squadron formed on 15 April 1955 under Atlantic Command for training purposes. It was composed of Wallaceburg, Portage and Minas initially. After Minas transferred to the West Coast, Sault Ste. Marie transferred to Halifax to take her place in December 1955.

HMCS Llewellyn and Revelstoke

Llewellyn was the training ship associated with HMCS Scotian in 1949. That summer, the ship made a tour of Newfoundland, after it became the 10th province of Canada. Llewellyn was tender to HMCS Brunswicker in 1961.

Revelstoke was tender to HMCS Cabot in 1951-2.

Llewellyn-class minesweepers were wooden-hulled. They displaced 228 tons and had a maximum speed of 9 knots (17 km/h; 10 mph). They were 119 feet 4 inches (36.37 m) long overall with a beam of 22 feet 0 inches (6.71 m) and a draught of 8 feet 8 inches (2.64 m). They had a complement of 3 officers and 20 ratings. They were armed with 1 .5-inch machine gun placed amidships and twin .303-inch machine guns on the bridge wings.

No photos of Coquitlam, Kalamalka and Lavallée are known to exist.

• Coquitlam pennant number J364
• Cranbrook pennant number J372
• Daerwood pennant number J357
• Kalamalka pennant number J395
• Lavallée pennant number J371
• Llewellyn pennant number J278 (postwar 141)
• Lloyd George pennant number J279 (postwar 142)
• Revelstoke pennant number J373
• Rossland pennant number J358
• St. Joseph pennant number J359

Daerwood constructed at Vancouver Shipyards Ltd. Launched 14 August 1943. Commissioned 22 April 1944 at Vancouver. Patrolled coast from Esquimalt to Prince Rupert until paid off 28 November 1945. Sold for commercial use 30 December 1946. Caught fire and sank at Bridgetown, Barbados, 13 October 1973.

Cranbrook constructed by Star Shipyards at New Westminster. Launched 5 June 1943. Commissioned 12 May 1944 at New Westminster. Patrolled west coast from Esquimalt to Prince Rupert until paid off 3 November 1945. Purchased by Nanaimo towing firm in November 1947. In 1950 registry disappeared from Lloyd's Registry.

Llewellyn constructed Chantier Maritime, Ile d'Orleans, Quebec. Launched 12 August 1942. Commissioned 24 August 1942 at Quebec City. Arrived at HAX 5 September, assigned to Halifax Local Defence Force. Spent rest of war performing sweeps of the approaches to Halifax Harbour. Following end of war, the minesweeper served as guardship for the reserve fleet at Halifax. The ship was paid off on 14 June 1946, but recommissioned on 25 July 1949 as tender at Saint John. The ship was paid off again on 31 October 1951. Sold 1957 for commercial use. Renamed Llewellyn II, the fishing vessel foundered off Cape Breton on 28 October 1960.

Lloyd George constructed Chantier Maritime. Launched 12 August 1942. Commissioned 24 August 1942 at Quebec City. Arrived at HAX 5 September and assigned to Halifax Local Defence Force. Spent rest of war performing sweeps of the approaches to Halifax harbour. Following war, used as bathythermograph vessel until 16 July 1948 when paid off. Sold 14 May 1951 to become floating restaurant at Bridgewater, Nova Scotia. Abandoned 10 years later.

Coquitlam built by Newcastle Shipping Co. Ltd, Nanaimo. Launched 5 Jan 1944. Commissioned 25 July 1944 at Nanaimo. Patrol duty Esquimalt to Prince Rupert until p.o. 30 November 1945. Sold October 1946, renamed Wilcox. Went aground on 17 June 1954 on Anticosti Island and written off.

Kalamalka built A.C. Benson Shipyard, Vancouver. Launched 29 December 1943. Comm. 2 Oct 1944 at Vancouver. Patrol duty Esquimalt to Prince Rupert until p.o. 16 November 1945. Sold 1946, burned and sank while fishing in Wallis Bay, BC on 18 March 1968.

Lavallée built A.C. Benson Shipyard, Vancouver. Launched 27 May 1943. Comm. 21 June 1944 at Vancouver. Patrol and degaussing vessel at Esquimalt and Prince Rupert until p.o. 27 Dec 1945. Sold 13 November 1947 to become fishing vessel of same name. Burned and sank near Burgeo, NF on 1 Mar 1967.

Revelstoke constructed by Star Shipyards at New Westminster. Launched 3 Nov 1943. Commissioned 14 July 1944 at New Westminster. Patrol duty Esquimalt to Prince Rupert until p.o. 18 Feb 1946. Taken to HAX, served as tender to HMCS Stadacona and Cabot before being p.o. for the final time on 23 Oct 1953. Sold 1957, renamed Shirley Ann in 1959, caught fire and sank off NF 12 Oct 1979.

Rossland constructed at Vancouver Shipyards Ltd. Launched 14 August 1943. Commissioned 15 July 1944 at Vancouver. Patrolled coast from Esquimalt to Prince Rupert until paid off 1 November 1945. Sold to Vancouver towing company 1946 and renamed La Verne. Resold 1971 to US buyer. Still afloat as late as 1988.

St. Joseph built by Newcastle Shipping Co. Ltd, Nanaimo. Launched 14 Sep 1943. Commissioned 24 May 1944 at Nanaimo. Patrol duty Esquimalt to Prince Rupert until p.o. 8 November 1945. Sold for commerical use, Mexican-flagged cargo vessel until registry deleted 1988.

River-class frigate

The River-class frigate design was an upgraded version of the Flower-class corvette, remedying many of the Flower class' issues as an ocean escort. The initial vessels were constructed for the Royal Navy and were named for rivers, however, in Canada, they were named for cities. Canada was informed of the design development in December 1940, but the plans were not delivered until late April 1941. The design was too large to fit through the canals on the St. Lawrence River, restricting the construction of the River-class ships to three shipyards, all with direct access to the sea. The first fifteen Canadian ships followed the standard British design.

The frigates measured 301 feet 4 inches (91.85 m) long overall and 283 ft 0 in (86.26 m) between perpendiculars with a beam of 36 ft 7 in (11.15 m) and a draught of 9 ft 0 in (2.74 m). They had a standard displacement of 1,445 long tons (1,468 t) and had increased flare and sheer forward to improve the vessel's dryness at sea. They were square amidships with deep bilge keels to alleviate rolling in heavy seas. They had a complement of 10 officers and 135 ratings.

The River class were powered by a steam created by two Admiralty three-drum boilers pumped to a vertical triple expansion engine turning two propeller shafts. The system creating 5,500 indicated horsepower (4,100 kW) giving the ships a maximum speed of 20 knots (37 km/h; 23 mph). They had a range of 7,200 nautical miles (13,300 km; 8,300 mi) at 12 knots (22 km/h; 14 mph).

The first 15 Canadian ships that followed the British design mounted a single 4-inch (102 mm) gun forward and one aft. The remaining Canadian ships mounted twin 4-inch guns forward and a single 12-pounder naval gun aft. The Canadian ships had eight 20 mm (0.79 in) cannon in four twin powered mounts for anti-aircraft defence. They also mounted four heavy machine guns. For anti-submarine warfare (ASW) the ships carried a Hedgehog ASW mortar forward and the frigates initially carried 100 depth charges, later rising to 145, to be fired from four throwers and two stern tracks and rails. Two of the throwers were located on the port side of the ship, and the other two on the starboard side. 30 charges were kept for the rails and racks and 32 for the the throwers.

The River-class frigates were equipped with the Type 147B Sword sonar and ASDIC which were used in conjunction to find submarines below the surface. The combination of the two allowed for the frigates to maintain tracking targets even while firing. For tracking surfaced submarines, HFDF was installed. HFDF searched for the communication signals of opposing submarines, which had to surface to communicate.

Prestonian conversion

Due to the rapid expansion of the Royal Canadian Navy during and following the Korean War, twenty-one retired River-class frigates were reacquired and modified to what became known as the Prestonian conversion. The conversion removed the Hedgehog mortar and replaced it with two Squid anti-submarine mortars placed on the enclosed quarterdeck. The forecastle deck, which initially extended two-thirds the length of the ship, was extended fully aft and walled, creating additional interior space for habitability and anti-submarine equipment. Furthermore, the hull forward was strengthened against ice.

The bridge was made larger and fully enclosed. The taller bridge structure in turn required a taller funnel and the new ASW weaponry required a larger tripod mast. All of the new upper works were constructed of aluminium to save weight. The generating machinery was altered from three steam and one diesel generator to two steam and two diesel generators. The revised figures for the frigates became a 1,570-long-ton (1,600 t) standard displacement and 2,360 long tons (2,400 t) at full load with a draught of 16 feet (4.9 m) at full load. The frigates now had increased range, capable of 9,600 nautical miles (17,800 km; 11,000 mi) at 12 knots.