On 6 April 2012 a Boeing Company 737-838 aircraft (B737), registered VH-VXI, on a scheduled passenger flight from Sydney, New South Wales to Darwin, Northern Territory was involved in a breakdown of separation with an Airbus Industries A330-243 aircraft (A330), registered B-6073, on a scheduled passenger flight from Melbourne, Victoria to Shanghai, China.

Both aircraft were operating under Instrument Flight Rules and were in airspace controlled by Brisbane Centre utilising radar.

The B737 and A330 were on converging tracks at Flight Level (FL) 360. As the aircraft approached Tindal, Northern Territory at 1342 Central Standard Time, a breakdown of separation occurred when the distance between them reduced to about 3.5 NM, before vertical separation was established. The incident occurred about 16 minutes after a handover between two Air Traffic Controllers.

As a result of a number of incidents involving handovers, Airservices Australia advised the ATSB that they had amended the handover procedure to require supervision and for the relinquishing controller to remain at the console to provide assistance until the accepting controller indicated that assistance was not required.

The incident highlighted the importance of separation assurance and thorough handovers.