OVERVIEW: The Annapolis-class destroyer escort (DDH) DELEX is a 2-shaft steam powered escort vessel intended primarily for anti-submarine warfare.

DETAILS: The two Annapolis-class destroyers are a version of the St. Laurent-class.  Unlike other units of that class which retrofitted aviation facilities, the Annapolis class incorporated the helicopter hangar from the start. 

These ships were among the first to take a new approach to helicopter operations from small warships. Unlike the British, who fitted a small helicopter (Westland Wasp) on their frigates with only a minimum of redesign, the RCN decided to use the far more capable and sophisticated CH-124 Sea King.

As part of the Destroyer Life Extension (DELEX) update, the class received the same sensor and communications upgrades that the St Laurent family of ships received. This including the installation of a new tactical data system (ADLIPS), updated radars and sonars, fire control and satellite navigation. They also received the new Canadian Tactical Towed Array Sensor or CANTASS, a long-range towed sonar array that replaced the older VDS. The class also received a new lattice mast, the AN/SPS-503 radar, and the AN/SPS-10D replaced the older, AN/SPS-10 model. The AN/SQS-502, AN/SQS-503 and SQS-10/11 sonars were removed and replaced by AN/SQS-505(V) in a fixed dome below the waterline. The Limbo mortar was removed to install the CANTASS. Additionally, a Super RBOC chaff system was installed during the refit and they also received 12.75-inch (324 mm) torpedo tubes enabling them to fire Mark 46 torpedoes.

Specifications:

Displacement: 3,420t
Length: 111.56 m
Beam: 12.8m
Draught: 4.01m
Propulsion: 2 shafts; 2 Babcock & Wilcox water tube boilers@616 psi; 2 English Electric geared turbines, 30,000 shp
Speed: 28kn
Complement: 228

Range: 8,463.6km @ 12kn

NOTES: IOC: 1964. Units in class: ANNAPOLIS (DDE265), NIPIGON (DDE266). The RCN had intended to place a six ship order under the Mackenzie-class of destroyer escorts; however, the last two vessels were built to the St. Laurent-class DDH design and were classed under the new Annapolis-class designation. Both ships spent the majority of their career split between Canada's Pacific and Atlantic coasts with the Annapolis being at Esquimalt and Nipigon at Halifax.



SOURCES:
"Annapolis Class Destroyer Escort Helicopter DDH Royal Canadian Navy." Seaforces Online - Naval Information. Accessed February 16, 2022. https://www.seaforces.org/marint/Canadian-Navy/Destroyer/Annapolis-class.htm. ; "ANNAPOLIS Class." Haze Gray & Underway - Naval History and Photography. Accessed February 16,2022. https://www.hazegray.org/navhist/canada/postwar/annapoli/. ; "Annapolis-class Destroyer." Wikipedia, the Free Encyclopedia. Last modified October 6, 2021. https://en.wikipedia.org/wiki/Annapolis-class_destroyer. ; Couhat, Jean L., and A. D. Baker. Combat Fleets of the World 1990/91: Their Ships, Aircraft, and Armament. US Naval Institute Press, 1990, pg. 55.