Annapolis-class Destroyer Escort

The Annapolis-class destroyer escort was a class of ships that saw service with the Royal Canadian Navy and Canadian Forces from the 1960s-1990s.

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.

The two Annapolis-class destroyers were built late enough to incorporate the helicopter hangar retrofitted to the St. Laurent-class. HMCS Nipigon underwent a DELEX (DEstroyer Life EXtension) refit in 1982 to upgrade combat, radar and weapons systems and HMCS Annapolis followed in 1984. Nipigon remained in the fleet until 1998 as a trials ship for the ETASS Mod 5 towed sonar system which was a precursor to the CANTASS (Canadian Towed Array Sonar System) that is currently fitted on the Halifax-class of frigates. Except for the replenishment ships HMCS Protecteur and Preserver, Nipigon was the last steam-powered warship to serve in the Canadian Forces.

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. The disadvantage of this approach is the fact that a considerable amount of surface area on the mothership has to be sacrificed to accommodate the helicopter. On the other hand, the helicopter itself is far more capable and can operate even in poor weather conditions: a considerable advantage in the polar region.

As Built

 * Type: Destroyer Escort
 * Service Period: 1964-1998
 * Characteristics:
 * Length: 366 feet (111.56 meters)
 * Beam: 42 feet (12.8 meters)
 * Draught: 23 feet 6 inches (7.16 meters)
 * Displacement: 3,420 long tons (3,475 tons) Full Load
 * Crew: 228
 * Propulsion: 2-shaft English-Electric geared steam turbines, 2 Babcock and Wilcox boilers, 30,000 shp (22,000 kW)
 * Range:
 * Speed: 28 knots (51.86 km/h)
 * Sensor Suite:
 * AN/SPS-10B surface search radar
 * AN/SPS-12 air search radar
 * AN/SQS-501 high frequency bottom profiler sonar
 * AN/SQS-502 high frequency mortar control sonar
 * AN/SQS-503 hull mounted active search sonar
 * AN/SQS-504 VDS medium frequency active search sonar
 * AN/UQC-1B "Gertrude" underwater telephone
 * AN/URN-20 TACAN radar
 * Mk.64 GFCS fire control with SPG-48 tracker (GUNAR)
 * Sperry Mk.2 navigation radar
 * Countermeasures:
 * AN/ULQ-6 jammer
 * AN/WLR-1C radar analyzer
 * AN/UPD-501 radar detector
 * AN/SRD-501 HF/DF
 * Armament:
 * 1 x FMC 3"/50 Mk.33 twin
 * 1 x Mk. NC 10 Limbo ASW mortar
 * 1 x Mk.4 thrower with homing torpedoes
 * Aircraft Carried: 1 x CH-124 Sea King ASW Helicopter
 * Midships helicopter deck and hangar with Beartrap.

DELEX Refit

 * Type: Destroyer Escort
 * Service Period: 1964-1998
 * Characteristics:
 * Length: 366 feet (111.56 meters)
 * Beam: 42 feet (12.8 meters)
 * Draught: 23 feet 6 inches (7.16 meters)
 * Displacement: 3,420 long tons (3,475 tons) Full Load
 * Crew: 228
 * Propulsion: 2-shaft English-Electric geared steam turbines, 2 Babcock and Wilcox boilers, 30,000 shp (22,000 kW)
 * Speed: 28 knots (51.86 km/h)
 * Sensor Suite:
 * AN/UQC-1B "Gertrude" underwater telephone
 * AN/SQR-19(V) CANTASS towed array sonar
 * Raytheon/Sylvania AN/SPS-502 surface search radar
 * Marconi AN/SPS-503 air search radar
 * AN/SQS-504 VDS medium frequency active search sonar
 * AN/SQS-505(V) hull mounted active search sonar
 * Mk.64 GFCS fire control with AN/SPG-515 tracker
 * Countermeasures:
 * AN/ULQ-6 jammer
 * AN/SLQ-501 intercept (CANEWS)
 * AN/SRD-501 HF/DF
 * Armament:
 * 1 x FMC 3"/50 Mk.33 twin
 * 2 x triple Mk.32 12.75 inch torpedo tubes firing Mk.44 or Mk.46 Mod 5 torpedoes
 * Aircraft Carried: 1 x CH-124 Sea King ASW Helicopter
 * Aviation Facilities: Midships helicopter deck and hangar with Beartrap.