the white light on a marker beacon indicator, but with a different audio rhythm from an inner marker or en-route marker. Fan marker The term fan marker refers to the older type of beacons used mostly for en-route navigation. Fan-type marker beacons were sometimes part of a non-precision approach and are identified by a flashing white light and a repeating dot-dash-dot signal. Recent editions of the FAA's AIM publication no longer mention fan markers. In August 2017 seven fan markers remain in service in the USA. See also AN/MRN-3 Transponder Landing System (TLS) References External links 2008 Federal Radionavigation Plan This FRS publication has detailed description of ILS and other navigational systems. Operational Notes on Visual-Aural Radio Range & Associated Marker Beacons a 1953 publication. International Telecommunication Union (ITU) Radio stations and systems ITU Radio navigation Aeronautical navigation systems Aircraft landing systems Beacons