Australia's transport safety regulator said on Friday it had launched an investigation into a fourth incident involving air traffic control at Sydney airport in less than a month after two planes were directed towards the same intersection on the ground.
The Boeing had been cleared to continue along a taxiway that the Airbus had been cleared to turn onto, it said.
The ATSB said there was no immediate risk of collision, but had launched an investigation to understand if there were any contributing factors in common with three other incidents at the airport over the last month.
"The evidence collection phase of the investigation will involve interviewing involved air traffic controllers and flight crew, retrieving and reviewing available recorded data, and the collection of other relevant information," the ATSB said.
A preliminary report is expected in six to eight weeks.
On July 27, two Qantas aircraft narrowly avoided a collision after a QantasLink Dash 8 completing a landing and a Qantas 737 whose pilots reported they had been cleared to cross the same runway came into conflict. The 737 was able to stop, though only after crossing the safety hold point.
On August 9, a Jetstar A320 had to brake suddenly on the tarmac to avoid colliding with a Qatar Airways Boeing 777, injuring a cabin crew member.
The same day, a Virgin Australia (VGN.AX) 737 cleared for takeoff spotted a Qantas aircraft crossing the runway ahead and stopped about 1 km (0.62 miles) short of the other plane, which had also been cleared to cross.
Separately, the ATSB said on Thursday it had received a report from an air traffic controller that staff at the airport had been unprepared for complex airspace and procedure changes resulting from the opening of a new international airport in the city's west.
The report, made in early June, said more than 50 controllers at the airport had responded to a union survey, with most expressing concern at the lack of time given to learn "an enormous amount of highly detailed and complex material" before the airspace changes came into effect on July 9.
The controller raised concerns of similarities to the air traffic control situation in Washington, D.C., ahead of a deadly midair collision in January 2025 where staff had pleaded with local management for changes in the months leading up to the accident.
In response, Australia's Civil Aviation Safety Authority, which investigated the report, found that Airservices Australia, the government entity employing air traffic controllers, had implemented appropriate training, procedures, and operational support arrangements relating to the changes.
