Pinetree Line

2400 Squadron was formed on 14 December 1949 within Training Command to "maintain and operate radar facilities required by No. 400 (F) Squadron (Auxiliary) and No. 411 (F) Squadron (Auxiliary) for the practice of air interception". The unit was equipped with the AMES-11C mobile radars mounted on trucks.

The squadron was located at the Eastville Avenue building at Scarborough Bluffs. The high high cliffs in this area were considered ideal for radar

On 22 March 1950, the Unit was renamed as 2400 Aircraft Control and Warning Unit (Reserve). 1 August 1951 saw 2400 AC&WU transferred from Training Command to Air Defence Command. On 1 November 1951, 2400 AC&W Unit (Reserve) was re-designated as 2400 AC&W Unit (Auxiliary). The unit was active in participating and exercising with the Regular AC&W Squadrons. The two most commonly visited units were Edgar and Falconbridge.

In 1958, the units new role was to "train Auxiliary personnel including those in the trades of Fighter Controller and Fighter Control Operator in all aspects of air control and warning operations and to maintain and operate radar and communications facilities as directed by AOC, ADC". Narrative reports on the Pinetree Line web site confirm that 2400 AC&W Squadron was active at RCAF Station Edgar, ON during the years 1953 to 1959, RCAF Station St. Margarets in 1957, RCAF Station Falconbridge in 1955, as well as RCAF Station Mont Apica in 1952.

2400 AC&W Squadron was disbanded on 31 January 1961 as a result of the implementation of SAGE into the RCAF. With SAGE, there was no longer a requirement for the Auxiliaries to be trained in manual operations to backup the Regular RCAF AC&W Squadrons.