Loss of separation involving a Beech Aircraft Corp 58, VH-GJZ and Aerospatiale AS.350B, and Aerospatiale AS.350B, 7 km east of Canberra, Australian Capital Territory, on 29 September 1995

At 1139 the Canberra approach controller cleared Hawk 02 to track to Canberra from the east-south-east at an altitude of 3,500 feet. Just after this VH-GJZ departed from runway 12, tracking via Bindook. The pilot had been told to turn left onto a heading of 070 degrees and climb to 4,500 feet. A short time later the approach controller passed the responsibility for Hawk 02 to Canberra tower, saying this aircraft was to track for a left base on runway 17. The pilot of Hawk 02 was given a visual approach and commenced descent.

At 1142 the pilot of VH-GJZ advised approach control he was climbing to 4500 feet and turning left onto a heading of 070 degrees. The approach controller realised that separation would be lost between VH-GJZ and Hawk 02. The controller told the pilot of VH-GJZ to stop the turn on a heading of 110 degrees. Horizontal separation reduced to about one mile before vertical separation was established. The pilot of VH-GJZ reported sighting Hawk 02 and was told to pass behind this aircraft, then turn left onto a heading of 040 degrees.

A third aircraft, callsign Squirrel 005, had been cleared direct to Canberra from the north-east at an altitude of 4500 feet. As a result of the controller's instructions to VH-GJZ this aircraft and Squirrel 005 were now on conflicting tracks. The pilot of Squirrel 005 was told to turn 30 degrees to the right and the pilot of VH-GJZ was told to climb to 7,000 feet. Horizontal separation between VH-GJZ and Squirrel 005 reduced below the minimum standard before vertical separation was established.

Significant Factors

The following factors were considered relevant to the development of the incident:

1 The approach controller did not satisfactorily plan the handling of the sequence.

2 The approach controller did not take timely steps to avoid potential traffic conflicts.