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

comparison with data collected by the Avdata service. Generally, aerodromes where
Avdata movement data was not available were not included in the movement group.
However, in some cases where Avdata was not available, but a large number of
occurrences warranted inclusion of the aerodrome in the comparison group, the
aerodrome operators were approached directly by the ATSB to provide either
collected or estimated movement data for the January 2003 to December 2008 period
(Karratha 11 , Broome, Geraldton, and Hervey Bay 12 aerodromes).
Using a combination of these movements data sources (from Airservices, further
movements data provided from the OAR, datasets purchased from Avdata Australia,
data provided by aerodrome operators, and movements data from individual CASA
aeronautical studies of non-towered aerodromes), a final set of 20 non-towered
aerodromes was established for further analysis of the relationship between traffic
mix and occurrence types.
In the interests of data reliability, transparency and impartiality, these 20 aerodromes
were selected for the movement group if they satisfied one or more of the following
criteria:
• were among the top 25 busiest non-towered aerodromes 13 in terms of total
movements (and complete movement information was available)
• were permanently non-towered for the period of the study (GAAP/Class D
aerodromes, and aerodromes such as Newcastle and Avalon where a partial ATC
presence exists were excluded)
• had a diverse mix of aircraft and operation types, including passenger transport
services utilising large aeroplanes
• had more than the expected number of occurrences reported to the ATSB between
1 January 2003 and 31 December 2008 that related to airspace use and procedures,
based on their estimated number of annual movements.
11 Karratha Aerodrome (YPKA) currently uses Avdata Australia to collect movement information;
however this arrangement began late in the reporting period. As a result, more complete movement
data was sourced directly from the Shire of Roebourne (WA).
12 Fraser Coast Regional Council (the operators of Hervey Bay Aerodrome) were unable to provide
detailed movements data from 2003 to 2008, and hence were excluded from a detailed traffic
analysis.
13 Excluding Class D/GAAP aerodromes, military, and other partially towered aerodromes (such as
Avalon, Pearce and Newcastle) which operate under non-towered aerodrome procedures outside of
ATC operating hours.
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