Airspace related - Other involving a Dassault Falcon E, VH-HFJ, 37 km west-south-west of Alice Springs VOR, Northern Territory, on 22 August 1997

An aircraft was flight planned to track from Alice Springs direct to Ayers Rock. When the plan was being processed by flight data staff, the routing was checked with a supervisor. The staff were instructed to generate flight progress strips to indicate that the aircraft would track via ANGAS. (Preferred routes for the area are via ANGAS to Ayers Rock and direct to Alice Springs from Ayers Rock). Approaching Alice Springs, the crew became aware that an aircraft was tracking from Ayers Rock to Alice Springs and would present a confliction for their descent. After passing Alice Springs, in order to give the controller adequate time to make arrangements, they informed the controller that their descent point would be 75 NM from Ayers Rock, whereupon the controller issued a descent clearance. The crew questioned whether the other aircraft would be a confliction. They indicated that their flight plan had been to track direct from Alice Springs to Ayers Rock. The aircraft was then issued with a clearance to track via ANGAS.

No operating limitation for the route from Alice Springs was evident on the enroute chart, so the pilot had planned via the direct track. After the incident he found that the preferred route was via ANGAS.