Flight charter company Rossair says it doesn't know what went wrong in the moments before one of its planes plunged to the earth in South Australia, killing all three people on board.
The Cessna Conquest came down near Renmark on Tuesday afternoon during a training flight, killing the company's chief pilot Martin Scott, 48, fellow pilot Paul Daw, 65, and Civil Aviation Safety Authority inspector Stephen Guerin, 56,
Rossair has grounded its operations, and says it will cooperate fully with investigations by the Australian Transport Safety Bureau and CASA.
Chief executive Warren Puvanendran would not speculate on a possible cause of the crash while those investigations were underway.
"At this stage, we simply don't know what happened," Mr Puvanendran told reporters on Wednesday.
"As a precaution, we have voluntarily grounded our operations."
Mr Puvanendran said the company had an "impeccable safety record".
"We have the people, the processes, the resources to make sure our operations run safely," he said.
"We've never had a major issue or an incident. So this a surprise.This is an incident that no-one can prepare for."
He said it was unclear when the company would resume flying, with that decision to be based on advice and recommendations from CASA.
"We'll have to take stock of what happened," he said.
"My priority at the moment is not to delve too deeply into the incident but to look after the families of the deceased and also our current employees."
The ATSB said the plane crashed near the Renmark Airport shortly after take-off on a return leg back to Adelaide.
A team of five investigators had been sent to the site to examine the scene, the wreckage, interview witnesses and to gather relevant data, including radar and radio transmissions.
The bureau plans to issue a preliminary report within 30 days and a final report within 12 months.
Rossair said the training flight had been planned for some time and the 37-year-old plane involved had flown other routes earlier on Tuesday without incident.
There were no issues with maintenance as far as Rossair was concerned.
While he had more than 40 years experience as a pilot, Mr Daw was training as he prepared to rejoin the company after working for some time as chief pilot at Adelaide's Bruce Hartwig Flying School.
The school said it was deeply saddened by the death of the "well-known, highly experienced and respected senior pilot".
"We will all miss our dear friend and valued colleague," it posted on Facebook on Wednesday.
Rossair also paid tribute to Mr Daw and, as chief pilot, said Mr Scott, had helped the charter company expand.
"The role of any chief pilot in an aviation organisation is one that requires leadership, mentoring and robust flying skills - and Martin delivered on all those accounts," it said.
CASA said Mr Guerin would be remembered by his colleagues as "passionate about aviation, meticulous about safety and widely respected".
