SYDNEY, AUSTRALIA — Airservices Australia has announced the redesigning of a standard instrument departure (SID) out of Sydney Airport in response to an incident involving a loss of separation between two commercial airliners.

The event occurred on Sep. 28, 2022, between a British Airways-operated Boeing 787-9 and a Qantas Airways-operated Airbus A330-200. The updated departure procedure aims to enhance air traffic control measures to ensure safer and more efficient operations.

According to the Australia Transport Safety Bureau (ATSB), both aircraft were cleared to use the same standard instrument departure (SID) after take-off, called DEENA SEVEN. The 787 took off from runway 16R at 15:08 local time, and the A330 departed shortly after.

As part of the standard instrument departure (SID) procedure, both the Boeing 787 and the Airbus A330 were expected to ascend to an altitude of 28,000ft. The SID required the planes to take a right turn towards the ANKUB waypoint once they passed the DEENA waypoint and climbed above 6,000ft.

The A330 operating a domestic service to Cairns, climbed faster than the heavier 787 operating a long-haul service to Singapore, resulting in the A330 turning inside the other aircraft.

“During the departure, the following aircraft climbed faster than the controller anticipated and turned towards the next waypoint inside the preceding aircraft, resulting in a loss of separation,” said ATSB.

The investigation by the Australian Transport Safety Bureau (ATSB) has revealed that the DEENA SEVEN SID design does not provide the necessary guarantees of safe separation between aircraft with different performance characteristics. According to the ATSB, the design of the SID requires that two separate conditions must be met before an aircraft can turn, meaning there is no way to guarantee that aircraft will turn at the same distance from the airport, therefore compromising separation assurance.

During the incident, the flight level separation between to airplanes was 600ft, and they were only 2.4nm away from each other. The British Airways crew then indicated that they had received a warning from the TCAS (Traffic Alert and Collision Avoidance System).

Airservices Australia has redesigned DEENA SEVEN SID in response to the incident.