TWO planes on the Gold Coast came within 150 metres of each other earlier this month, sparking an investigation by transport safety authorities.
Fairfax and Seven News reported an AirAsia plane was taking off from the airport about 11.42am on July 21 when the Jetstar plane was descending.
The AirAsia Airbus A330 was heading to Auckland while the Jetstar Airbus A320 was arriving from Victoria's Avalon Airport.
The two planes were 152 metres apart - about half the 300 metre distance required.
"The flightpaths of the inbound Airbus A320 and the outbound Airbus A330 resulted in a loss of separation,'' the Australian Transport Safety Bureau said in a report on its website.
"Both aircraft received a traffic collision avoidance system (TCAS) resolution advisory (RA), with the crew of the A320 conducting a climb to increase separation."
Traffic collision avoidance system (TCAS) is an aircraft collision avoidance system.
It monitors the airspace around an aircraft for other aircraft equipped with a corresponding active transponder and gives warning of possible collision risks.
When an RA is issued pilots are expected to respond immediately to the RA unless doing so would jeopardise the safe operation of the flight.
There was no damage to either aircraft, no one was injured and it is not known whether the passengers even noticed.
Jetstar declined to comment to Seven News while the investigation is underway.
An AirAsia spokesman said its pilots followed the directions of the air traffic controller and the airline was "co-operating fully" with the investigation which is being led by the Air Transport Safety Bureau.
"AirAsia X confirmed that the pilots received warning from traffic collision avoidance system upon take off and the crew responded to the resolution advisory by reducing the vertical speed according to flight safety procedures," the spokesman said.
"The aircraft took off safely and continued its journey without any subsequent events."
Update your news preferences and get the latest news delivered to your inbox.