If you wish to contribute or participate in the discussions about articles you are invited to join SKYbrary as a registered user


A332 / A333, en-route, North West Australia, 2012

From SKYbrary Wiki

Revision as of 21:25, 21 March 2015 by Integrator1 (talk | contribs)


On 31 March 2012 an Airbus A330-300 (PK-GPA) being operated by Garuda on a scheduled passenger flight from Bali (Denpasar) to Melbourne and an Airbus A330-200 (PK-GPO) being operated by Garuda on a scheduled passenger flight from Bali (Denpasar) to Sydney were both independently involved in losses of separation assurance because of issues arising from the short notice temporary implementation of TIBA procedures in an area of upper airspace following due to a shortage of controllers.


An Investigation was carried out by the Australian Transport Safety Bureau (ATSB).

It was noted that the basis for the determination that a Serious Incident had occurred was that two aircraft had operated in controlled airspace without ATC awareness because of issues related to the temporary implementation of TIBA procedures in a TRA when the provision of normally mainly procedural ATC service in an area of upper airspace controlled from Brisbane ACC could not be maintained. An overview of the airspace involved is shown below:

The Kimberley (KIY) and Cable (CBL) sectors where the Temporary Reserved Area was implemented and TIBA procedures notified showing the adjacent FIRs (reproduced from the Official Report)

It was established that on the evening of 30 March 2012, the two controllers who had been rostered to man the combined Kimberley (KIY) and Cable (CBL) sectors from 2300 that day until 0615 on 31 March had both called in at short notice to advise that they "were unable to attend for their shift". In both cases this notification was described as for "a legitimate personal reason". No replacements could be found, although it was possible to cover the beginning and end of this shift period by obtaining agreements from controllers on the shifts prior to and following the un-covered period to respectively slightly extend / begin earlier their duty periods. Contingency plans to designate a TRA which would temporarily withdraw ATS and substitute TIBA procedures between 0015 and 1615 local time (EST) on 31 March were activated and a NOTAM was issued to advise of these arrangements. The necessary regulatory approval was also obtained.

Whilst the TRA was in place, the console for the affected sectors was monitored by an upper airspace line manager at the Brisbane ACC who was designated as the Contingency Response Manager (CRM).

Further Reading