Investigators are examining how two Qantas flights at Sydney Airport were given clearance to take routes that could have caused a collision on Tuesday.

The Australian Transport Safety Bureau said a Qantas 737 coming in from the Gold Coast was heading west on the ground and had clearance to turn right.

At the same time, a Qantas Airbus A321 preparing to depart for Melbourne also had clearance to turn, which would have put it in the other plane’s path.

“As the Airbus approached... the crew observed the Boeing approaching from the left and stopped the aircraft,” the bureau said.

Scrutiny over the operations of air traffic controllers has increased in the past month, following a series of incidents primarily at Sydney Airport.

The safety bureau is also investigating a runway incursion and rejected take-off of Virgin Australia flight VA555 from Sydney to Perth and Qantas flight QF728 from Sydney to Ayers Rock Airport that occurred on August 9. On the same day, a Jetstar A320 almost collided with a Qatar Airways Boeing 777. That incident was initially described as a near collision. But the bureau later called it a “proximity event”.

On the August 18 investigation, the bureau said: “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.”

Qantas has been approached for comment.

More to come.

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