Communication and self-separation in non-controlled airspace

SafetyWatch_icon_1.pngSafety concern

It is difficult for pilots to identify other aircraft through visual observation alone.

The ATSB often receives reports from pilots that another aircraft is flying too close to them in uncontrolled airspace. Not surprisingly, three quarters of these reports involve pilots flying within 10 nautical miles (18.5 kilometres) of a non-controlled aerodrome.

In nearly three quarters of all near-collisions reported to the ATSB, at least one pilot had no prior warning of the other aircraft in their vicinity.

Insufficient communication between pilots operating in the same area is the most common cause of safety incidents near non-controlled aerodromes.

What can you do?

  • Get a radio, and always make sufficient broadcasts so that other pilots know your intentions – even when you think there is no nearby traffic.This will increase your chance of detecting other aircraft before it's too late. Making at least the minimum radio broadcasts and using good radio practice alerts other pilots to nearby aircraft and help to reduce the risk of a mid-air collision or a near miss.
  • Maintain a lookout for other aircraft at all times.There may be a variety of aircraft of different sizes and performance levels all operating at the same time in the same airspace, and some aircraft may not have a radio that is working or is tuned to the correct frequency. Do not rely solely on monitoring your radio to achieve traffic awareness. 
  • Achieve radio alerted see-and-avoid by making all the recommended broadcasts within 10 nautical miles of a non-towered aerodrome.A search for other traffic is eight times more effective when a radio is used in combination with a visual lookout than when no radio is used.
  • Use the same procedures at all non-towered aerodromes, unless otherwise stated in the En Route Supplement Australia.Following known, standard traffic procedures helps pilots to anticipate the likely position of other aircraft.
  • Be aware that any radio-equipped aircraft could be conducting base leg entry or straight-in approaches at non-towered aerodromes.Large commercial jet aircraft landing at non-towered aerodromes often make straight-in approaches, but any VHF radio-equipped aircraft are allowed to make these types of approaches.
  • Avoid overflying aerodromes where possible, and take note of instrument flight rules inbound and outbound routes.Aircraft traffic is relatively dense near aerodromes, particularly on the final approach path to an active runway and on the runway itself.

More information

The ATSB Short Investigations Bulletin Near collision special edition, released in September 2016, contains ten investigation reports highlighting the issue of near collisions occurring in the vicinity of non-controlled aerodromes. The bulletin contains helpful guidance to assist pilots in avoiding a near collision when operating in non-controlled airspace.

The ATSB booklet A pilot’s guide to staying safe in the vicinity of non-controlled aerodromes outlines many of the common problems that occur at non-controlled aerodromes, and offers useful strategies to keep yourself and other pilots safe.

External references

Related: SafetyWatch
Last update 23 October 2017