Operations resources


Class G communications


Certified Air/Ground Radio Service AIP GEN 3.4

A certified air/ground radio service (CA/GRS) is an aerodrome-based radio information service, which may operate at non-controlled aerodromes. The service provides pilots with operational information relevant to the particular aerodrome. The service is operated by or for the aerodrome operator within the published hours, on the CTAF assigned to the particular aerodrome. It is not an Airservices Australia or RAAF-provided air traffic service.

The CA/GRS does not provide any separation advice.

The callsign of the service is the aerodrome location followed by ‘radio’; for example: ‘Ayers Rock radio’. The radio operators of the service have been certified to meet a CASA standard of communication technique and aviation knowledge appropriate to the service being provided.

The CA/GRS is provided to all aircraft operating within the designated broadcast area for the specific location. Refer to ERSA for the location-specific designated broadcast areas.

When a CA/GRS is operating, pilot procedures are unchanged from the standard non-controlled operating and communication procedures. ERSA includes location-specific information related to procedures.

The CA/GRS information helps pilots to make informed operational decisions. Pilots retain authority and responsibility for the acceptance and use of the information provided.

Aircraft making the normal inbound or taxiing broadcast receive a responding broadcast from the CA/GRS operator, conveying the following information:

  • confirmation of correct CTAF
  • current known, relevant traffic in the vicinity of the aerodrome and on its manoeuvring area. Traffic information may include some or all of the following information
    • the aircraft type, callsign, position and intention
    • where circuit flying is in operation, general advice on the number of aircraft  in the circuit, and position in the circuit if relevant.

  • weather conditions and operational information for the aerodrome.
    This may include:

    • runway favoured by wind or noise abatement
    • runway surface conditions
    • wind direction and speed
    • visibility and present weather
    • estimated cloud base
    • aerodrome surface temperature
    • aerodrome QNH.

This information will be provided by means of an automatic aerodrome information service (AAIS) broadcast on a discrete published frequency (similar to ATIS) during CA/GRS operating hours, or on request to the CA/GRS operator. Pilots should monitor the published AAIS frequency before making a taxiing or inbound broadcast

Other local operational information, relevant to the safety of operations at the aerodrome, will also be broadcast.

The CA/GRS will provide emergency services call-out if requested by the pilot in an emergency or, if in the opinion of the operator, a call-out is warranted.

The weather information provided by the service is derived from approved measuring equipment, which meets BoM aeronautical precision standards. QNH provided by a CA/GRS, or AAIS may be used to reduce landing, circling and alternate minima in accordance with AIP ENR 1.5 (QNH Sources).

The CA/GRS operator may act as a representative of an air operator (where formal agreement with the operator has been established) for the purposes of holding SARWATCH.

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