Pinetree Line Miscellaneous

Reserve/Auxiliary Aircraft Control and Warning Units


The Reserve Auxiliary Aircraft Control & Warning Units began to form in 1949 with the last of these units fully available by late 1951. The reason behind the Reserve units was "to provide a pool of trained personnel that would be able to augment, in an emergency, the operation of Regular Aircraft and Control Units (ACWUs) on a 24 hour basis."

These Reserve units were spread across Canada in the major population centres for two reasons. The first was the larger locales would have a large pool of young men, and later women, to recruit from. The second, and by no means less important reason, was the fact that each of the centres had some sort of Regular or Reserve military establishment from which they could expect support. In the majority of the cases, these units were RCAF stations and squadrons. Others such as Quebec City and Halifax could somewhat reluctantly count, on the Army and Navy, to assist the fledgling AC&W Units.

The Reserve AC&W Units, all re-designated as Auxiliary on 1 November 1951, were issued with a four number designator that began with the number 2. The next three numbers were always a 4 and the remaining numbers ran the gamut from 01 to 55. These designations usually followed a sequence that appeared to form a set of numbers based on Auxiliary or even Regular Air Force flying units such as 2401, 2402, 2416 and 2420. It must be noted here that the Auxiliary AC&W Units and Squadrons had nothing to do with their flying counterparts. While some of the units were, in fact, formed around personnel and equipment that had been in the flying unit with the same number such as No. 403 (FB) Squadron, the numbering was coincidental and for convenience sake, as those flying units with the same numbers were located in the same geographical area as the AC&W Squadrons.

The Auxiliary units were equipped with the AMES-11C mobile radar and associated equipment, that was mounted in a variety of trucks. These trucks formed into convoys and were able to deploy anywhere as directed by either squadron, Group, or Command Headquarters. These vehicles and their operators deployed far and wide to not only Regular AC&W Stations in their areas but to other locations in the field to exercise with both Auxiliary and Regular flying squadrons. Additionally, personnel regularly deployed to Regular Squadrons during weekends, summer camps, and for extended periods of time to augment their Regular counterparts as this was their original reason for formation. These Regular Squadrons included not only those manned by the RCAF, but also those sites operated by the USAF.

When first formed, the Auxiliary units usually reported to the local RCAF Reserve/Auxiliary Headquarters, or if there was not a local headquarters, then to the closest headquarters such as Montreal. The Auxiliary converted to an emergency and rescue role in the late fifties. When the role of the Auxiliary flying squadrons changed to the aforementioned role, their directing Headquarters, to which the ACWUs also reported, switched from their former Groups and Commands to Air Transport Command.

As the ACWUs were created for, and occupied with air defence, it was decided that these squadrons would report directly to Air Defence Headquarters. This change came into effect in October 1958.

All of the Auxiliary ACWUs achieved Squadron status on 1 December 1953. They were also all to share the same fate with the coming of SAGE. As SAGE was an automated system and all auxiliaries were only trained with the manual system, it was decided that they could no longer augment the Regular Force and would not be trained to operate SAGE as a cost-cutting measure. All of the Auxiliary Aircraft Warning & Control Squadrons were disbanded by the end of 1961 after performing more than a decade’s worth of valuable and much appreciated service.


Summary of Auxiliary AC&W Units

AC&W Unit Location Formation Closure
2400 Toronto, ON 14 December 1949 31 January 1961
2401 Montreal, QC 15 December 1948 31 August 1961
2402 Winnipeg, MB 1 October 1950 31 March 1961
2403 Calgary, AB 1 June 1952 1 June 1961
2405 Halifax, NS 1 May 1950 31 August 1961
2416 Ottawa, ON 15 July 1950 31 December 1961
2420 London, ON 15 June 1951 31 May 1961
2424 Hamilton, ON 1 October 1950 31 January 1961
2442 Vancouver, BC 1 April 1950 31 March 1961
2450 Sherbrooke, QC September 1949 31 December 1961
2451 Ste. Anne de Bellevue, QC 15 April 1951 1 August 1951
2451 Windsor, ON 4 January 1954 31 May 1961
2452 Quebec City, QC 15 April 1951 31 December 1961
2453 Three Rivers, QC 1 September 1951 31 August 1961
2455 Victoria, BC 15 January 1951 31 March 1961


Updated: October 30, 2004