flight service station

flight service station (FSS)

Air traffic facilities that provide pilot briefings, en route communications, and VFR (visual flight rules) search and rescue services; assist lost aircraft and aircraft in emergencies; relay ATC (air traffic control) clearances; originate NOTAMs (notices to airmen); broadcast aviation weather; receive and process IFR (instrument flight rules) flight plans; and monitor en route NAVAIDS (navigational aids). In addition, at selected locations, FSSs provide en route flight advisory services (flight watch), take weather observations, issue airport advisories, and advise customs and immigration of transborder flights. On aeronautical charts, heavy line boxes indicate FSSs. Frequencies 121.5, 122.2, 243.0, and 225.4 are normally available at all FSSs and are not shown above the boxes. All other frequencies available at FSSs are shown. Frequencies transmit and receive those except those followed by R or T. A hairline box without frequencies and a controlling FSS name indicates that no FSS frequency is available.