OVERVIEW: The Iroquois- class aka Tribal-class DDG is a 2 shaft, COGOG-powered, helo-capable destroyer intended primarily for ASW.  
 
DETAILS: The Iroquois were designed for long-range ASW warfare, using two CH-124 Sea King helicopters.  To support these large helicopters, the class had a large flight deck and a two-helicopter hangar.  It also had a haul down device, allowing for helicopters landing operations in heavy seas.  A passive-tank anti-rolling system was fitted to improve stability at low speeds.  A distinctive feature of the design was the two paired stacks (termed "Playboy Bunny" stacks) angled outboard to avoid corrosion of antennas by stack gases. 

In addition to the CH-124, the class used a hull-mounted SQS-501 and SQS-505 VDS for ASW search.

The class ships was armed with a quick-firing OTO Melara 5"/54, providing good anti-surface/naval gunfire support capability, as well as close-ranged anti-aircraft defence. Point anti-aircraft defence was provided by NATO Sea Sparrow missiles. ASW attack capability was provided by two Mk.32 triple torpedo launchers, and helicopter launched torpedoes. 

During the Gulf War of 1990/91, HMCS ATHABASKAN was upgraded with a  mine-avoidance sonar, Phalanx 20mm CIWS and Blowpipe and Javelin MANPADs.

Specifications:

Displacement: 4,700t
Length: 128.92m
Beam: 15.24m
Draught: 4.42m
Propulsion: 2 shafts; 2x Pratt & Whitney FT12AH3 cruise gas turbines, 7400 shp; 2x Pratt & Whitney FT4A2 boost gas turbines, 50,000 shp;
Complement: 285
Speed: 29kn
Range: 4,500 nm (8,300km) @ 12kn

NOTES: IOC 1970.  Units in class: IROQUOIS (DD 280), HURON (DD 281), ATHABASCAN (DD 282), ALGONQUIN (DD 283).  When USS PRINCETON was disabled after hitting a mine in the northern Gulf, ATHABASKAN escorted a tug to her rescue and escorted both ships back out through the minefield.


SOURCES:  Prezelin, Bernard. The Naval Institute Guide to Combat Fleets of the World, 1990-1991. US Naval Institute Press, 1990., pg. 55-6; "Iroquois-class Destroyer." Wikipedia, the Free Encyclopedia. Last modified April 16, 2022. https://en.wikipedia.org/wiki/Iroquois-class_destroyer. ;"Mackenzie Class Destroyer Escort DDE Royal Canadian Navy." Seaforces Online - Naval Information. Accessed April 30, 2022. https://www.seaforces.org/marint/Canadian-Navy/Destroyer/Iroquois-class.htm. ; 
McClearn, Sandy. "IROQUOIS Class." Haze Gray & Underway - Naval History and Photography. Accessed April 30, 2022. https://www.hazegray.org/navhist/canada/postwar/tribal/.
