------- landing without a clearance is a scary occurrence.
RobShan,
At the time, the Avalon aerodrome was uncontrolled, the tower had closed about an hour earlier.
The whole incident was tracked by Melbourne radar, so ATSB (and, presumably, CASA) have complete details of the track and heights of the aircraft.
There is significant terrain in the immediate vicinity of the airfield.
Tootle pip!!