The Australian Transport Safety Bureau has sent extra staff to Perth to investigate a light plane crash which claimed the lives of two men.
Frank Davey, 60, and Daniel Mark Berinson, 41, had taken a joy flight to Northam but failed to return on Sunday night.
Their bodies were found ten kilometres east of Mundaring yesterday along with the wreckage of the twin-engine plane.
Bureau spokesman Richard Batt says investigators will work with police to prepare a report for the coroner.
“That will include aspects to do with the aircraft itself, mechanical, what flight was intended, aspects to do with the pilot and the maintenance of the aircraft, so this is just routine that we look at this wide range of aspects in our investigations.”
Mr Batt says parts of the aircraft will be taken for further testing and the investigation will take some time.
“The first phase of the investigation is gathering information and what we will typically do is in about 30 days put out a preliminary report which just basically outlines that factual information, but then analysing the data we have and preparing a final report could well take a number of months.”
Police are yet to determine who was flying the plane at the time of the crash.
Both men were qualified pilots.