Accident Overview
At 0906 Eastern Standard Time on 28 July 2004, a Piper Aircraft Corporation PA31T Cheyenne, registered VH-TNP, departed Bankstown, New South Wales on a private instrument flight rules (IFR) flight to Benalla, Victoria. The aircraft carried one pilot and five passengers.
Flight and Approach
Instrument meteorological conditions at Benalla required an instrument approach. The pilot reported initiating a Global Positioning System (GPS) non-precision approach (NPA) to Benalla.
Search and Wreckage
When the pilot did not report landing as expected, a search began. Later that afternoon, a search helicopter crew located the burning wreckage on the eastern slope of a tree-covered ridge, approximately 34 km southeast of Benalla. All six occupants sustained fatal injuries. The aircraft was destroyed by impact forces and a post-impact fire.
Probable Cause Findings
The official investigation identified the following significant factors:
- The pilot was unaware that the aircraft had deviated from the intended track.
- The route flown lacked overflight of any ground-based navigation aids.
- The sector controller did not inform the pilot of the deviation from the cleared track.
- The sector controller cancelled route adherence monitoring alerts twice without confirming the pilot's tracking intentions.
- Cloud cover prevented the pilot from using external visual cues to detect the deviation.
- The pilot began the approach at an incorrect location.
- The aircraft's radio altimeter did not provide adequate protection against terrain collision.
- The aircraft was not fitted with a terrain awareness warning system (TAWS).