HMCS St. Laurent was a that served in the Royal Canadian Navy and later the Canadian Forces from 1955–1974. She was the lead ship of her class, the first modern warship designed and built in Canada. St. Laurent was laid down on 24 November 1950 by Canadian Vickers at Montreal. She was launched on 30 November the following year and was commissioned into the Royal Canadian Navy on 29 October 1955 and initially carried the pennant number DDE 205 as a destroyer escort. Prime Minister Louis St. Laurent was present at her commissioning. She was reported to have cost $15,000,000 to build. She underwent conversion to a destroyer helicopter escort (DDH) in the early 1960s and was officially re-classed with pennant DDH 205 on 4 October 1963. Design and description The need for the St. Laurent class came about in 1949 when Canada joined NATO and the Cold War was in its infancy. The Royal Canadian Navy (RCN) was assigned responsibility for anti-submarine warfare (ASW) and controlling sea space in the western North Atlantic. The St Laurent class were built to an operational requirement much like that which produced the British Type 12, and were powered by the same machinery plant. The rounded deck-edge forward was adopted to prevent ice forming. The vessels were designed to operate in harsh Canadian conditions. They were built to counter nuclear, biological and chemical attack conditions, which led to a design with a rounded hull, a continuous main deck, and the addition of a pre-wetting system to wash away contaminants. The living spaces on the ship were part of a "citadel" which could be sealed off from contamination for the crew safety. The ships were sometimes referred to as "Cadillacs" for their relatively luxurious crew compartments; these were also the first Canadian warships to have a bunk for every crew member since previous warship designs had used hammocks. As built, the ships were long overall with a beam of and a draught of . The destroyer escorts displaced standard and at deep load. The destroyer escorts had a crew of 12 officers and 237 enlisted. Armament The St. Laurent class was fitted with twin /L50 caliber guns in two mounts for engaging both surface and air targets. The ships were also fitted with two single-mounted guns. The class's anti-submarine armament consisted of a pair of triple-barreled Mk. NC 10 Limbo ASW mortars in a