Instrument departure procedure design

Following the construction of a new hangar adjacent to runway 28 right (28R) at Archerfield Airport, Queensland, the Australian Transport Safety Bureau (ATSB) received a number of submissions asserting that the building infringed safety standards or reduced flight safety.

Drawing on an independent third-party review, the ATSB determined that the building does not breach obstacle limitation surfaces. The ATSB also conducted an initial examination of the instrument departure procedure from runway 28R. The ATSB found that the procedure complied with the extant instrument departure design requirements, but identified an ambiguity in the guidance for designing instrument departure procedures.

The ATSB assessed that this ambiguity could lead to inconsistent expectations about the extent of clearance from obstacles provided to aircraft when pilots were following an instrument departure procedure. This had the potential to increase the risk of a collision with an obstacle. In response, on 30 May 2008, the (then) Executive Director of the ATSB commenced a safety issue investigation in accordance with sections 21 and 23 of the Transport Safety Investigation Act 2003.

As a result of that investigation, the Civil Aviation Safety Authority and Airservices Australia have, in consultation, reviewed their understanding of how the design standards for instrument departure procedures should apply in Australia. They have also re-examined the runway 28 instrument departure procedure at Archerfield in the light of that review and have advised that they intend to amend the requirements for instrument departures from runway 28R.

The potential for inconsistent interpretation of the instrument departure procedure design requirements has also been notified to the International Civil Aviation Organization instrument flight procedures panel, which monitors the international standards for the design of instrument procedures.