Pinetree Line

1955 Air Defence Command National Archives of Canada



Air Defence Command was formed initially in late 1948, as a planning group at Air Force Headquarters, Ottawa. In July 1949, the responsibility for the overall air defence of Canada was assigned to this group. The organization was set up as an autonomous headquarters and in November of the same year was relocated at RCAF Station St. Hubert.

On June 1, 1951, the group attained Command status and was renamed Air Defence Command. Functionally, the Command is responsible for the Air defence of all Canada, and exercises operational and administrative control of air and ground units from Newfoundland to the west coast and northward from the 49th parallel to the Arctic seas.


From a headquarters in eastern Canada, and a subordinate headquarters on the west coast, Air Defence Command is organized to undertake a variety of tasks. These tasks include:

[a] - The planning and establishing of air defence systems.

[b] - Maintaining and operating warning and fighter control systems.

[c] - The directing of fighter aircraft against air attack.

[d] - The operational training of aircrew in fighter operations.

[e] - The continued exercise and training of staffs in their operational role.

[f] - The direction, supervision and control of anti-aircraft defence.


In order to fulfill its assigned role, Air Defence Command headquarters, located at St. Hubert, PQ, operates fighter bases and ground environment units such as the Pinetree Radar network from coast to coast. A subordinate headquarters, 12 Air Defence Group at Vancouver, is responsible for the air defence of the west coast. In addition, the command directs the training of a number of Auxiliary air and ground units which supplement the regular formations. A vast Ground Observer Corps reaching into the far north backs up the radar warning systems.


Operational control of air defence units is exercised through the Combat Operations Centre located at the Command headquarters. This control is further decentralized through Group and Sector headquarters.

A fighter Operational Training Unit is located at Chatham, NB and an all-weather Operational Training Unit is located at Cold Lake in northern Alberta.

The command functions on a 24 hour "Alert" basis, and large scale joint training schemes, viz "Exercise Signpost", "Tailwind" and "Check Point", with the United States Air Force, Air Defence Command, as well as daily lesser practices exercise the aircrews and staffs in an operational role.

An important factor influencing the air and other operations in Air Defence Command is the weather, which varies from temperate to arctic. The extremes of the arctic must be taken into account when considering personnel requirements the maintenance of aircraft, mechanical equipment, hangars, runways and living quarters.


Vital to air defence operations is communications including an adequate back-up system. A vast network of telephone, teletype, landline, microwave and radio-telegraphy links together all elements of Air Defence Command. So complete is the system that within seconds a telephone call can be made or other communication established between the RCAF ADC HQ and the USAF ADC HQ or to any unit from Gander, Newfoundland, to Holberg on the west coast.

Throughout the Command lines of supply are lengthy and every medium of transport, i.e., road, rail, air, tractor train and inland waterway, must be utilized. The short navigation season on inland waterways requires the stockpiling of freight at the railheads well in advance of the Spring breakup. Consequently, all projects in the remote northern regions call for logistic planning many months in advance.

The isolated radar bases involve the building of self-contained communities in remote areas, and in addition to the operational element, housing, power, sewage, road construction and general municipal maintenance must be maintained.

Attendant problems are:

[a] - The very short construction season.

[b] - The absence of local labor.

[c] - The absence of local building equipment and material.

[d] - The necessity for logistic planning and programme implementation at least a year ahead of any heavy construction.

[e] - The provision of year-round water supplies and sewage disposal facilities.

The provision of medical care for service personnel and their dependents is a vexing problem in remote areas but one that must be met. Moreover, suitable cold weather clothing, insect control, adequate emergency kits and rations for survival after forced landing, and the psychological hazards of isolation during the long Canadian winters are subjects of continuing research and experiment.

Morale of personnel in isolated units is a vital consideration. To this end a policy of large-scale construction of married accommodation and recreation facilities at isolated bases, the payment of supplemental allowances in certain areas and a rotation policy have been implemented.


In essence, the continued development of procedures and techniques to keep pace with the emergence of new weapons, aeronautical and electronic, as well as to overcome the obstacles of terrain, distance and climate is considered the key to the continued provision of an effective air defence of Canada, and indeed, North America.


NOTE: This article was obtained from the National Archives of Canada for use on the Pinetree Line web site. There is no indication as to when the article was written but I would guess it to have originated in early 1955 as there is mention of 12 Air Defence Group at Vancouver. The 12 Air Defence Group was re-designated to 5 Air Division effective 1 September 1955 as per Organization Order 3.1