[Peetwo]

Another ATSB report for PAIN peer review -

Investigation number: AO-2014-044


Investigation status: Completed
 

• Final Report
  
  

Final Report

Download Final Report
[PDF: 988KB]
 

 
Alternate: [DOCX: 1.82MB]
 

What happened


At 1253 Central Standard Time on 27 February 2014, a Boeing Company 737-8FE, registered VH-VOM (VOM), was radar vectored when outside controlled airspace, near Darwin, Northern Territory. Radar vectoring outside controlled airspace was not permitted, and may have brought VOM into conflict with aircraft that were unknown to air traffic control.

What the ATSB found


The ATSB found that weather in the Darwin area resulted in the majority of inbound aircraft diverting around storm cells. These diversions increased workload for the Approach East controller. The increased workload resulted in the controller using non-standard phraseology and not cancelling radar vectors prior to VOM leaving controlled airspace. Additionally, the flight crew of VOM had not reported ‘clear of weather’ as expected by the controller. This resulted in a lack of shared understanding between the flight crew and the controller.

What's been done as a result


Following this occurrence the Department of Defence introduced theoretical and simulator-based training to assist air traffic controllers to resolve unusual situations using clear communication and direction. The training reinforces positive and assertive control measures, skills that are especially necessary in high workload situations.

Safety message


This occurrence highlights that effective communication is essential for a shared understanding between flight crew and air traffic controllers. On this occasion, the use of non-standard phraseology by both parties resulted in different expectations and delay. Additionally, coordination between controllers is an essential component of their duties; however, this is not transmitted via radio. As a result, silence on an air traffic control frequency should not be interpreted by flight crew as an indicator of low workload for the controller.

For what seems to be a significant breakdown of ATC (Military) procedure, this report seems to lack emphasis on the significant safety issues identified in the investigation. Also note that the only 'safety action' record is in the summary above i.e. What's been done as a result.

MTF...P2