Breakdown of separation - SAAB 340, VH-SBA and Beechcraft B58, VH-VFG, near Taree Airport, New South Wales, on 1 December 2010

On 1 December 2010, at 1412 Eastern Daylight-saving Time, a breakdown of separation occurred between a Beech Aircraft Corporation Barron BE58 (BE58), registered VH-VFG, and a SAAB Aircraft Company S340B (S340), registered VH-SBA, near Taree Airport, New South Wales (NSW).

The BE58 was a private flight from Bankstown to Port Macquarie, NSW and the S340 was a scheduled passenger service from Taree to Sydney, NSW. On departure, the S340 was issued a clearance by air traffic control (ATC), with an altitude requirement intended to establish the S340 above the BE58 on a crossing track. When ATC reassessed the proximity of the aircraft and determined that the altitude requirement would not ensure separation, they issued the BE58 with a vectoring instruction.

The separation between the two aircraft reduced to below the required standards. Separation was re-established when the S340 reached 10,000 ft on climb.

This incident highlights the importance for air traffic controllers to continually monitor and reassess their separation plans and implement changes to assure that the required separation standards will be established and maintained. Furthermore, the provision of timely and appropriate traffic information to flight crew, by air traffic control, can significantly enhance pilots' situational awareness.

Airservices Australia (Airservices) has advised that they are conducting a systemic review of a number of Breakdown of Separation occurrences, with outcomes from that review to be considered in terms of further safety improvement. As a short-term safety intervention, Airservices will be conducting an awareness program for Air Traffic Controllers following the publication of this report.