Piper PA-28R-201, VH-PRF

A British Aerospace 146 (BAe 146) was arriving at Alice Springs from the north-east and was instructed by air traffic control to make a visual approach to runway 12 via a left circuit.

A Piper Cherokee Arrow (Arrow) was also arriving at Alice Springs on a flight from Coober Pedy and was instructed to track via visual flight rule route "VFR Route 6". That route tracked via the Stuart Highway, south-west of the aerodrome. As the aircraft passed Mount Polhill (20 NM from the aerodrome) the pilot was cleared to track via the gaol and to then make a visual approach to runway 06.

When the BAe 146 was on final approach the crew sighted the Arrow approximately 1 NM ahead and descending through their level. They commenced a go-around and manoeuvred to the right to ensure that they passed behind that aircraft.

The pilot of the Arrow had misinterpreted some of the controller's instructions and had tracked for a circuit because he was not set up for a straight-in approach. However, in carrying out that action he had not informed the controller of his change of plan and his inability to carry out the instructions received.

Although the controller was looking for the Arrow in order to provide a visual service, he did not see the aircraft because the pilot had been tracking in a direction that the controller was not expecting.