The role of 3FS was to co-ordinate all of the intelligence information from the various D/F stations and VAOC posts, decide on the most appropriate response and then advise the appropriate fighter or bomber squadrons to respond. 3FS was in telephone and radio contact with all of the anti-aircraft, searchlight, RDF and HF/DF stations in the Townsville area. All air raid warnings were initiated from this bunker by red, yellow and white flares. 103 FCU was disbanded in Townsville on 21 January 1945. There was also HQ located in North Ward, Townsville.