Incident Overview
On 4 October 2002 at approximately 0900Z, a PA24-400 aircraft registered ZS-DZZ was involved in an incident at Rustenburg Aerodrome. The aircraft was operating a private flight with one person on board. The weather at the time was fine with calm winds.
Sequence of Events
The pilot was accompanied by an Avionics technician for a flight in the General Flying Area near Britz to perform an operational test of the new Garmin 430 system fitted to the aircraft. Approximately 15 minutes after take-off, the pilot experienced a partial radio failure and the avionics system became inoperative. He elected to divert to Rustenburg but during extension of the undercarriage he experienced a total electrical failure. The pilot then utilized the undercarriage emergency extension system and the visual indicators showed that the undercarriage appeared to be down and locked. Upon landing, the aircraft rolled for approximately 150m when the right-hand main undercarriage collapsed followed by the nose and left-hand main undercarriage.
Injuries and Damage
There were no injuries reported. The aircraft damage was not specified in the fact-sheet.
Probable Cause
The probable cause of the incident is twofold: The electrical system 90 amp circuit protector to the alternator and voltage regulator contact point was completely worn and loose causing arcing and a short circuit inside the circuit protector. The most probable cause for the undercarriage to collapse is that the pilot failed to utilize the emergency extension system as prescribed.
Conclusion
This incident highlights the occurrence of electrical system failure and subsequent undercarriage collapse during an emergency diversion. No further analysis is provided beyond the stated probable cause.