The two men killed in a helicopter crash in Western Australia's Wheatbelt had been supporting an event in their own aircraft.
The men, one aged in his 50s and the other in his 70s, were members of the Royal Aero Club of WA.
In a statement, club chief executive Alan Wilson said: "It is with great sadness that we can confirm that the two fatalities in the helicopter crash in the vicinity of Cowcowing Lakes yesterday were club members participating in their private aircraft supporting the local Koorda Fly-In event.
"On behalf of the Royal Aero Club of Western Australia, we extend our deepest sympathies and condolences to the families, friends and club members involved."
It was not an official club event.
A search was prompted by the Australian Maritime Safety Authority's joint rescue coordination centre just before 4:00pm when the Robinson 22 helicopter failed to arrive at Jandakot airport.
The helicopter was located crashed in the vicinity of the Cowcowing Lakes in Booralaming, south-west of Koorda, about 220 kilometres north-east of Perth.
Police attended the scene and confirmed there were no survivors.
Investigators to map accident site
The Australian Transport Safety Bureau (ATSB) is investigating the incident.
"Over the coming days, ATSB investigators will survey and map the accident site and collect any relevant components for further examination and analysis at the ATSB's technical facilities in Canberra," Chief Commissioner Angus Mitchell said in a statement.
"They will also obtain and review any recorded data, weather information, witness reports and aircraft operator procedures and maintenance records," Commissioner Mitchell said.
"Should any critical safety issues be identified at any stage during the course of the investigation, the ATSB will immediately notify relevant parties so appropriate safety action can be taken."
'Mushy and muddy' crash site difficult to access
WA Police Acting Inspector Kareene Santoro said accessing the area had been a challenge.
"The only way in is via foot," she said.
"It's more of a salt lake so the ground isn't hard and it's quite mushy and muddy.
"It's definitely not a sight that you see every day but, quite a traumatic scene as you can imagine, quite horrific injuries."
Inspector Santoro said the men flew from Jandakot with other aircraft on Saturday.
"From there everything went smoothly," she said.
"They spent the night at Koorda and the following day they all left around the same time and the helicopter didn't arrive at the scheduled time it was due to arrive in Jandakot.
"That was reported through to the Jandakot air tower who then got in contact with the JRCC (AMSA Joint Rescue Coordination Centre) who then progressed their search for the aircraft."
She said the last time the men were spoken to was late on Sunday morning.
They were expected at Jandakot by about 2:35pm.
The ATSB will publish a report detailing the contributing factors to the crash when the investigation concludes.
WA police will prepare a report for the coroner.
Police are appealing for anyone with information, or who saw the helicopter leading up to the crash, to call Crime Stoppers on 1800 333 000.
