Canadian Forces Air Defence Command

Air Defence Command was a command of the Royal Canadian Air Force and later the Canadian Armed Forces, active from 1951 to 1975.

Originally, post-war plans called for air defence to be the responsibility of reserve, auxiliary squadrons only. Vampire jet fighters and older P-51 Mustangs were earmarked for these squadrons. With the rise of the "Iron Curtain" and the increasing tension in Europe, a change was seen as necessary and regular, full-time squadrons became the force's frontline.

In December 1948, No. 1 Air Defence Group was created in Ottawa, Ontario. In November 1949 Group Headquarters moved to RCAF Station St. Hubert, Quebec. No. 1 Air Defence Group became Air Defence Command in June 1951. The command reached its highest strength in 1955, by which time nine Regular Force squadrons (flying Avro Canada CF-100 Canucks) and ten Auxiliary squadrons (flying Vampires and Mustangs) fell under its control. Among the reserve/Auxiliary squadrons was No. 401 Squadron RCAF, flying from St. Hubert and Montreal. De Havilland Vampires served in both operational and air reserve units (Nos 400, 401, 402, 411, 438 and 442 Squadrons RCAF) until retirement in the late 1950s when they was replaced by the Canadair Sabre.

Among the CF-100 units were:

As equipment capability increased, and the perceived Soviet bomber threat diminished, the requirement for numbers decreased, and the nine CF-100 squadrons were replaced by five CF-101 squadrons, which later fell to three. The auxiliary squadrons also lost their air defence role. At the same time, the Pinetree Line, the Mid-Canada Line and the DEW Line radar stations, largely operated by the RCAF, were built across Canada because of the growing Soviet nuclear threat.

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