Sec.  87.421   Frequencies.

   The Commission will assign VHF frequencies after coordination with the FAA.
   Frequencies in the following bands are available to control towers and RCOs.
   Channel spacing is 25 kHz.

   118.000–121.400 MHz

   121.600–121.925 MHz

   123.600–128.800 MHz

   132.025–135.975 MHz

   (a) The frequency 123.100 MHz is available for use by control towers and
   RCOs  at  special aeronautical events on the condition that no harmful
   interference  is  caused to search and rescue operations in the locale
   involved.

   (b) Frequencies in the bands 200.0–285.0 and 325.0–405.0 kHz will normally
   be assigned only to control towers and RCOs authorized to operate on at
   least one VHF frequency. The Commission may assign frequencies in these
   bands to entities that do not provide VHF service in cases where granting
   such an application will not adversely affect life and property in the air.

   (c) Frequencies listed in the introductory paragraph of this section are
   available to control towers and RCOs for communications with ground vehicles
   and aircraft on the ground. The antenna heights shall be restricted to the
   minimum necessary to achieve the required coverage. Channel spacing is 25
   kHz.

   (d) 121.500 MHz: emergency and distress only.

   [ 53 FR 28940 , Aug. 1, 1988, as amended at  55 FR 30464 , July 26, 1990;  63 FR 68958 , Dec. 14, 1998;  69 FR 32886 , June 14, 2004;  71 FR 70680 , Dec. 6, 2006]