Investigation number
AO-2010-050
Occurrence date
Location
74 km NW of Tamworth Airport
State
New South Wales
Report release date
Report status
Final
Investigation level
Short
Investigation type
Occurrence Investigation
Investigation status
Completed
Aviation occurrence category
Loss of separation
Occurrence class
Incident
Highest injury level
None

On 1 July 2010, at 1003 Eastern Standard Time, a breakdown of separation occurred between an Airbus Industrie A320-232 aircraft and Boeing Company 767-338 aircraft, about 40 NM (74 km) to the north-west of Tamworth, New South Wales. The aircraft were operating on crossing tracks, with an angular displacement between the tracks of about 50°. Both aircraft were operating at standard cruising levels. The enroute air traffic controller first identified the confliction about 2 minutes before the separation breakdown occurred, when both aircraft were maintaining FL360 and there was 26.2 NM (48.5 km) between their lateral positions. An instruction to climb to FL370 was issued to the flight crew of the 767. When there was 14.6 NM (27.04 km) between the aircraft, the controller subsequently instructed the flight crew of the 767 to expedite their aircraft's climb. Shortly before a 1,000 ft separation standard between the 767 and A320 was established, the radar data indicated that longitudinal separation had reduced, below the required standard of 5NM (9.26 km), to 3.8 (7.04 km) NM.

This incident highlighted the importance of the provision of timely and appropriate traffic information to flight crew by air traffic control, in that it can significantly enhance pilots' situational awareness.  It also supported the opportunity for flight crew to enhance the situational awareness of air traffic control, such as in providing direct information regarding individual aircraft performance.

Airservices Australia (Airservices) has advised that they are conducting a systemic review into the number of breakdown of separation occurrences. Outcomes from that review will be considered in terms of further safety improvement. In addition, Airservices has implemented a Compromised Separation Recovery training module for enroute air traffic control groups.

Aircraft Details
Manufacturer
The Boeing Company
Model
767
Registration
VH-OGG
Serial number
24929
Operation type
Air Transport High Capacity
Sector
Jet
Departure point
Sydney, NSW
Destination
Cairns, Qld
Damage
Nil
Aircraft Details
Manufacturer
Airbus
Model
A320
Registration
VH-VNC
Serial number
3275
Operation type
Air Transport High Capacity
Sector
Jet
Departure point
Brisbane, Qld
Destination
Melbourne, Vic.
Damage
Nil