Airservices is Australia's air navigation service provider - we provide air traffic control, aviation rescue and fire fighting and air navigation services.


We are investing approximately $1 billion over five years on upgrading and modernising our infrastructure and facilities. This includes air traffic control technology, new fire vehicles, stations and associated equipment.

Project updates

02 February 2018 | ILS Marker Beacons: Feedback Sought

The distance to touchdown information for the Instrument Landing System (ILS) distance has traditionally been provided by Marker Beacons installed at specific locations under the final approach path.

The purpose of the Middle Marker is to indicate that the pilot should make visual contact with the runway or abandon the approach, whilst the purpose of the Outer Marker is to provide height, distance, and equipment functional checks in the final stages of the approach.

Most Airservices Marker Beacons were installed prior to 2006 when ICAO standards specified a preference for Marker Beacons be provided with an ILS. Current ICAO standards permit the distance to touchdown information to be provided by either Distance Measuring Equipment (DME) or the Global Navigation Satellite System (GNSS) which provide a better method of performing an ILS approach when compared with Marker Beacons, because they provide a continuous measurement for the duration of the approach rather than at a single point.

Along with the United Kingdom and New Zealand, Airservices has been progressively fitting a low power frequency-paired DME to its ILS with a view to subsequently decommissioning Marker Beacons. The DME fitment is planned to be completed by the end of 2018, including:

  • Adelaide RWY 23

  • Alice Springs RWY 12

  • Brisbane RWY 01

  • Cairns RWY 15

  • Canberra RWY 35

  • Darwin RWY 29

  • Essendon RWY 26

  • Hobart RWY 12

  • Launceston RWY 32

  • Melbourne RWYs 16 and 27

  • Perth RWYs 21 and 24

  • Sydney RWYs 07, 16R and 34L

  • Townsville RWY 01

Whilst currently working with CASA’s National Operations and Standards division, Airservices is in parallel, seeking feedback on whether any Marker Beacons are still, or are expected to continue to be used for any specific reason. Please provide feedback by 31 March 2018. 

Feedback can be provided using the contact form, selecting “ILS Marker Beacons” as the subject.