Flight Details
The flight was planned to check onboard survey equipment. After departing Jandakot, the aircraft operated south of the airfield for about 80 minutes. The pilot then advised extending operations east over the Darling Ranges.
Witness Observations
Several witnesses sighted the aircraft over the foothills heading easterly. They reported that the engines were not operating normally. Shortly afterward, the aircraft was observed passing over a dam wall at an altitude of about 25 feet, heading down a valley in a northerly direction before disappearing from sight.
Wreckage Examination
Inspection of the wreckage indicated that the aircraft collided with two 30-meter-high trees in a nose-high attitude at low forward airspeed, then fell to the ground below. At impact, neither engine was delivering power.
Fuel System Findings
The fuel system was relatively intact and contained only nine litres of fuel.
Probable Cause
It was determined that the engines failed due to fuel starvation following the exhaustion of the useable fuel onboard the aircraft. The pilot was then faced with attempting a landing in unsuitable terrain. Evidence indicates that the aircraft departed Jandakot with both the fuel quantity indicating systems unserviceable. Although the maintenance documentation for the aircraft did not indicate that these systems were unserviceable, it is believed that the pilot was aware of the maintenance state of the aircraft before departure.