Aviation safety issues and actions

Appreciation of the significance of transpositions

Issue number: AO-2008-078-SI-01
Who it affects: Electricity transmission line testers
Issue owner: Aeropower Pty. Ltd.
Transport function: Aviation: General aviation
Background: Investigation Report AO-2008-078
Issue release date: 09 December 2010
Current issue status: Adequately addressed
Issue status justification:

Since the accident, the powerline maintenance provider and the helicopter operator have put into place a range of measures that ensure that crews are given the information about transpositions.

Safety issue description

Neither the maintenance provider, nor the helicopter operator appreciated the potential significance of mid-span transposition information to the joint testing task.

Proactive Action

Action number: AO-2008-078-NSA-138
Action organisation: Powerline maintenance provider
Action status: Closed

The powerline maintenance provider advised that, immediately following the accident, it:

Suspended all operations of the helicopter operator until it was satisfied that all appropriate safety procedures were in place.

Commissioned an independent audit to report on certain aspects of [the helicopter operator’s] operations including safety management systems and training procedures.

In addition, the powerline maintenance provider advised of the following amendments to its operational procedures:

Operational changes

Prior to the incident a debrief was held with [the helicopter operator’s] crew prior to the commencement of each planned maintenance job. We now require that [the helicopter operator] is to provide a formal documented debrief to [us] and the [asset owner] after each planned maintenance job. The exceptions to this directive are that and incident occurring during flight must be reported immediately and that because of work load the maximum time within which to hold a debrief is one week.


As advised earlier [we] have retained an external auditor to report on the safety and operational practices of [the helicopter operator]. Audit recommendations have been adopted.

ATSB comment:

The ATSB is satisfied that the action taken by the powerline maintenance provider adequately addresses the safety issue.

Proactive Action

Action number: AO-2008-078-NSA-139
Action organisation: helicopter operator
Action status: Closed

In response to this accident, the operator has indicated that it will:

Communicate with individual power companies to obtain their known hazard locations for with respect to Airborne Operations.

Information on transposition locations is now included in the job package.

ATSB comment:

The ATSB is satisfied that the action taken by the helicopter operator adequately addresses the safety issue.

Last update 18 February 2014