§  87.107   Station identification.

   (a) Aircraft station. Identify by one of the following means:

   (1) Aircraft radio station call sign.

   (2) The type of aircraft followed by the characters of the registration
   marking ("N" number) of the aircraft, omitting the prefix letter "N."
   When communication is initiated by a ground station, an aircraft
   station may use the type of aircraft followed by the last three
   characters of the registration marking. Notwithstanding any other
   provision of this section, an aircraft being moved by maintenance
   personnel from one location in an airport to another location in that
   airport may be identified by a station identification consisting of the
   name of the company owning or operating the aircraft, followed by the
   word "Maintenance" and additional alphanumeric characters of the
   licensee's choosing.

   (3) The FAA assigned radiotelephony designator of the aircraft
   operating organization followed by the flight identification number.

   (4) An aircraft identification approved by the FAA for use by aircraft
   stations participating in an organized flying activity of short
   duration.

   (b) Land and fixed stations. Identify by means of radio station call
   sign, its location, its assigned FAA identifier, the name of the city
   area or airport which it serves, or any additional identification
   required. An aeronautical enroute station which is part of a
   multistation network may also be identified by the location of its
   control point.

   (c) Survival craft station. Identify by transmitting a reference to its
   parent aircraft. No identification is required when distress signals
   are transmitted automatically. Transmissions other than distress or
   emergency signals, such as equipment testing or adjustment, must be
   identified by the call sign or by the registration marking of the
   parent aircraft followed by a single digit other than 0 or 1.

   (d) Exempted station. The following types of stations are exempted from
   the use of a call sign: Airborne weather radar, radio altimeter, air
   traffic control transponder, distance measuring equipment, collision
   avoidance equipment, racon, radio relay, radionavigation land test
   station (MTF), and automatically controlled aeronautical enroute
   stations.

   [ 53 FR 28940 , Aug. 1, 1988, as amended at  71 FR 70676 , Dec. 6, 2006]