Aviation safety issues and actions

Convergent air routes and airspace sectorisation

Issue number: AO-2013-161-SI-01
Who it affects: All Augusta and Tailem Bend en route controllers, and associated airspace users
Issue owner: Airservices Australia
Transport function: Aviation: Airspace management
Background: Investigation Report AO-2013-161
Issue release date: 05 March 2015
Current issue status: Adequately addressed
Issue status justification:

The ATSB is satisfied that the safety action undertaken, and action in progress, will satisfactorily address the safety issue.

Safety issue description

The convergence of many published air routes overhead Adelaide, combined with the convergence point being positioned on the sector boundary of the Augusta and Tailem Bend sectors, reduced the separation assurance provided by strategically separated one-way air routes and increased the potential requirement for controller intervention to assure separation.

Proactive Action

Action number: AO-2013-161-NSA-019
Action organisation: Airservices Australia
Date: 05 March 2015
Action status: Closed

Airservices Australia (Airservices) reported on 1 September 2014 that:

The Airservices SkySafe Taskforce – Airspace Stream is reviewing air routes in respect to the following criteria:

  • Identify elements of route structure and airspace usage which generate the highest risk;
  • Mitigate risks by reducing conflicting traffic streams, increasing systemisation and reducing the impact of human error;
  • Examine the effectiveness of existing protocols for the regular review of route structure and airspace usage, with specific attention to emerging risks presented by traffic growth

The Taskforce is undertaking a review of the Australian airspace design that contributes to risk. Due to a legacy design feature requiring air routes to be from Navigation Aid to Navigation Aid, the Taskforce is considering that with the advent of GPS [Global Positioning System] and improved aircraft navigation capability the need to track via Navigation Aids may no longer remain in many cases.

There is also consideration to providing more flexible route structures using modern navigation technology to create traffic directional flows and remove convergence points.

In addition, on 12 February 2015, Airservices reported that:

Furthermore Airservices confirms that the initiatives identified as part of the Operation SkySafe Taskforce are on-going. Airservices has commenced a holistic review of the air route network to address the safety issue identified in the report; to consider the impact and opportunities arising from the ADS-B [Automatic Dependant Surveillance Broadcast] and GNSS [Global Navigation Satellite System] mandates; and the capabilities that may be delivered with the new oneSKY air traffic management system.

Last update 05 March 2015