Loss of separation involving a Piper PA-28-181, VH-TXN and Fokker B.V. F28 MK 4000, VH-EWA, 2 km south-south-west of Melbourne, Victoria, on 23 June 1994

The crew on VH-EWA were conducting circuit training at Melbourne Airport. On the base leg turn for runway 34 the crew reported sighting another aircraft which had passed above them.

The other aircraft was VH-TXN, which had entered the Melbourne control zone without a clearance. The pilot of VH-TXN was proceeding from Tyabb to Shepparton and the pilot was intending to track around the southern and western boundaries of the zone. No contact was made with the aircraft until the pilot later called on the Radar Advisory Service (RAS) frequency at Rockbank.

Subsequently the aircraft again entered the zone without a clearance near Sunbury. The aircraft was not on the RAS frequency at the time. Subsequently RAS made radio contact, and the pilot was given radar headings to clear the zone near Beveridge.

Later checking of the plan for VH-TXN showed the pilot had made calculation errors in estimating the appropriate headings to fly and also errors in the time intervals. Enroute navigation errors also occurred.

Significant Factors

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

1. Poor flight planning by the pilot of VH-TXN.

2. Poor inflight navigation procedures by the pilot of VH-TXN.