The ATSB was advised that:
Airservices does not support the finding indicating that our processes do not ensure that newly endorsed controllers had sufficient skills and techniques to manage the high workload situations. Airservices training and checking processes, which are also subject to ongoing regulatory oversight, ensure that controllers are appropriately trained and assessed to be competent to perform roles in their licensed environment with varying traffic volume, complexity and workload levels.
To further enable equitable workload management, the Nullarbor (NUL) and Nullarbor Low (NLO) Sectors were re-sectorised into three (3) Sectors (WBRIFRT/ESP) in November 2012. In addition, Airservices has also established an ATC Workload and Complexity Reference Group to determine a suitable workload model to be used by ATC Shift Managers to monitor and forecast ATC workload on a sector by sector basis. This is aimed at further managing and mitigating workload-related risks.
In response to this safety issue also being identified in ATSB investigation report AO-2012-012, Airservices reported additional safety action related to the airspace sectors involved in that occurrence.
Although Airservices disagreed with the identified safety issue, the ATSB is satisfied that the actions taken by Airservices since the incident satisfactorily address the concerns that gave rise to the identification of this safety issue.