Mackenzie-class destroyer

HMCS Mackenzie off San Diego, in 1992
Class overview
Name:	Mackenzie class
Builders:	Canadian Vickers Ltd., Montreal Victoria Machinery Depot Ltd., Victoria Burrard Dry Dock Ltd., North Vancouver Davie Shipbuilding Ltd., Lauzon
Operators:	Royal Canadian Navy  Canadian Forces
Preceded by:	Restigouche class
Succeeded by:	Annapolis class
Planned:	6
Completed:	4
Retired:	4
General characteristics
Type:	Destroyer escort
Displacement:	2,380 t (2,380.0 t) full load
Length:	371 ft (113.1 m) wide load 366 ft (111.6 m) oa
Beam:	42 ft (12.8 m)
Draught:	13 ft 6 in (4.1 m)
Installed power:	2 × Babcock & Wilcox boilers 30,000 shp (22,000 kW)
Propulsion:	2 shafts 2 × English-Electric geared steam turbines
Speed:	28 kn (51.9 km/h; 32.2 mph)
Complement:	228 regular, 170–210 training
Sensors and processing systems:	1 × SPS-12 air search radar 1 × SPS-10B surface search radar 1 × Sperry Mk.2 navigation radar 1 × SQS-501 high frequency bottom profiler sonar 1 × SQS-502 high frequency mortar control sonar 1 × SQS-503 hull mounted active search sonar 1 × SQS-11 hull mounted active search sonar
Electronic warfare & decoys:	1 × DAU (replaced by SRD 501) high frequency direction finder 1 × WLR 1C radar analyzer 1 × UPD 501 radar detector
Armament:	1 × 3-inch/70 Mk.6 Vickers twin mount forward (Qu'Appelle had 3-inch/50 twin) 1 × 3-inch/50 Mk.33 FMC twin mount aft 2 × Mk NC 10 Limbo ASW mortars 2 × single Mk.2 "K-gun" launchers with homing torpedoes 1 × 103 mm Bofors illumination rocket launcher

The Mackenzie-class destroyer was a class of warship used by the Royal Canadian Navy and Canadian Forces from the 1960s–1990s. Six such ships were envisioned, of which four were completed to this specification. The last two hulls were completed to the post DDH conversion St. Laurent-class design (which included helicopter hangars); they were designated as the Annapolis class instead. The four Mackenzie-class destroyers spent most of their service in the Pacific Ocean, used primarily in a training role. Their only significant update was the DELEX (destroyer life extension) program, which were completed between 1982 and 1985 and updated their navigational radar and their sonar.

The initial design for what became known as the Mackenzie class was for an enlarged version of the St. Laurent class. Designed in 1957, they were to be 1,000 tonnes (980 long tons) heavier, 50 feet (15 m) longer and have engines that were 20,000 horsepower (15,000 kW) stronger than those installed in the St. Laurents. They would also have improved radar and sonar installed. Instead, budget issues forced a repeat of the previous Restigouche class, with changes intentionally minimized. Four ships were ordered in 1957, two more in 1958. However, costs for each of the ships rose to $28 million.

In 1959, the design of the final two ships of the class was altered to incorporate the changes made to the St. Laurent class. These two ships then became a separate class, known as the Annapolis class. The remaining four Mackenzies were essentially improved Restigouches, with improved habitability and better pre-wetting, bridge and weatherdeck fittings to better deal with extreme cold.

The ships measured 366 feet (112 m) in length, with a beam of 42 feet (13 m) and a draught of 13 feet 6 inches (4.11 m). The destroyer escorts displaced 2,380 tonnes (2,380 t) fully loaded and had a complement of 290.