Safety in the vicinity of non-towered aerodromes - Australian ...

In particular, pilots’ broadcasting their intentions when turning onto final is especially
important. Seeing objects on the runway is difficult from the air, and these may
include stationary or backtracking aircraft, aircraft lining up for takeoff, ground
vehicles or maintenance personnel. Seeing other aircraft in the air, such as aircraft on
straight-in approaches, is equally difficult. A 2004 review by the ATSB of the 37
mid-air collisions involving general aviation (GA) aircraft in Australia between 1961
and 2003 found that almost 80 per cent (n = 29) occurred in or near the circuit area,
with a third of these involving aircraft on final approach or the base-to-final turn.
Most of these collisions occurred where a faster aircraft descended upon the aircraft in
front. Ground collisions (which contributed to several accidents at non-towered
aerodromes between 2003 and 2008) can also occur on runways after landing. The
risk of both ground collisions and mid-air collisions can be reduced by making a
turning final broadcast as a warning to other pilots on approach or on the runway.
The necessity for the other circuit broadcasts depends upon the amount and type of
traffic in the circuit or approaching the circuit, as well as their separation and flow.
They are a matter of judgement for the pilot. If the traffic flow is established,
frequency congestion might be a consideration when deciding on which circuit
broadcasts to make. In comparison, if no other aircraft are heard or seen in the circuit,
the pilot should consider making every possible broadcast in the off chance that there
is another aircraft operating in their vicinity that they are unaware of.
In situations where one or more pilots do not broadcast appropriately, or are
experiencing radio difficulties, there is the potential for a breakdown in situational
awareness. This may result in an airprox or some form of conflict or reduced safety
margin between an aircraft and other aircraft, ground vehicles, or parachutists.
For this reason, it is essential to maintain a vigilant lookout, even when appropriate
broadcasts have been made on the CTAF.
While broadcasts should be made where a pilot deems they will improve situational
awareness and reduce the risk of a collision, making unnecessary broadcasts that have
no safety value (radio chatter) contributes to frequency congestion on the CTAF, and
can be a source of distraction for other pilots. The following occurrence is a good
example of the risks of unnecessary radio chatter.
Occurrence number 200506849
As the aircraft was taxiing for departure, the pilot of an arriving aircraft persisted in asking the
female pilot of a departing aircraft questions of a personal nature over the radio. The female
pilot reported that the chatter distracted her from the task of taxiing, resulting in the left wing
striking the `Welcome' archway of the aerodrome as she was manoeuvring to avoid the arriving
aircraft. The impact resulted in a hole in the leading edge of the aircraft wing approximately
60 cm inboard from the wingtip.
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