The air traffic controller overseeing an apparent near miss between two Qantas passenger aircraft hasn't been stood down, it has emerged.
Air navigation services provider Airservices Australia, who employs the traffic controller, says the staff member has been moved to another role but has not been fired.
The spokesman explained that it was standard procedure for controllers to be relieved of their normal duties after such incidents.
"That's for the safety of the traffic controllers as well," the spokesman told AAP on Saturday.
"Any incident, no matter what it is, would worry them. You don't want them worried and having to try to also focus on their job."
Collision avoidance systems were set off as a Sydney-to-Perth plane came too close to a Perth-to-Sydney plane over the Great Australian Bight on Friday afternoon.
The plane travelling from Sydney had been granted permission by air traffic control to climb.
Qantas says the Airbus A330 aircraft had a "loss of separation".
"Our pilots followed standard operating procedures in re-establishing the required separation distance," the airline said in a statement.
The Australian Transport Safety Bureau (ATSB) has begun an investigation which will include examining radar and audio data and interviewing air traffic controllers and flight crew.
It says the incident occurred just after midday (AEST), 19 kilometres west of Adelaide, when the flight one plane had begun to climb from 38,000 feet to 40,000 feet after being cleared to do so.
"Soon after, the controller cancelled the clearance and the aircraft descended back to 38,000 feet," the ATSB said.
It said the flight crew of the second plane received a resolution advisory alert from the aircraft's traffic collision avoidance system, requiring immediate action.
The ATSB expects to complete its investigation later this month.
The Civil Aviation Safety Authority says it will wait until investigations are concluded before it decides whether any action is needed.