Created Wednesday, Apr 7th 2021 07:07Z, last updated Wednesday, Apr 7th 2021 07:07Z
A Singapore Airlines Airbus A380-800, registration 9V-SKQ performing flight
SQ-231 from Singapore (Singapore) to Sydney,NS (Australia), was on final approach to Sydney's runway 16R when the aircraft encountered windshear. In response the crew commenced the windshear escape procedure and went around while descending through about 1300 feet MSL. Air Traffic Control instructed the crew to turn right onto a heading of 270 degrees, the crew read back to heading but omitted the direction of turn, ATC did not correct the incomplete read back. The crew turned left instead of right. A potential loss of separation occured with a Dash 8 on final approach to runway 16L, ATC instructed the A380 to immediately turn left and climb and instructed the Dash 8 to immediately turn right and thus maintained separation between the two aircraft, however, another conflict arose between the Dash8 and a Boeing 737 on final approach to runway 16R. The conflict was also resolved. The A388 positioned for another approach to runway 16R and landed without further incident about 23 minutes after the go around.
Australia's Transport Safety Board (ATSB) released their final report concluding the probable causes of the incident were:
Contributing factors
- The flight crew misheard an air traffic control turn instruction, likely due to a combination of the high cockpit workload associated with the missed approach and their expected turn direction.
- The flight crew omitted the direction of the turn during the readback, which was not corrected by air traffic control. The absence of the readback correction by air traffic control, combined with the misheard turn instruction, resulted in the aircraft being turned in the wrong direction.
The ATSB analysed:
What happened
On 9 February 2020, an Airbus A380 aircraft, registered 9V-SKQ was being operated by Singapore Airlines on a scheduled passenger service from Singapore to Sydney, New South Wales.
During the approach to runway 16 right at Sydney, the aircraft encountered windshear and in response, the flight crew commenced the windshear recovery procedure and missed approach. During this time, air traffic control (ATC) instructed the flight crew to turn right onto a heading of 270°. The flight crew read back the heading, however, did not include the direction of the turn. Air traffic control did not correct the incomplete readback and the flight crew commenced turning the aircraft left instead of right.
Air traffic control issued a safety alert to the flight crew, advised them of a Bombardier DHC-8 aircraft about 6 NM (11 km) on final for runway 16 left, and instructed them to turn right and climb immediately. Air traffic control then instructed the flight crew of the DHC-8 to make a right turn in order to maintain separation with the A380. This resulted in a loss of separation between the DHC-8 and a Boeing 737 aircraft on approach to runway 16 right.
What the ATSB found
The ATSB found that the flight crew were likely experiencing high workload as a result of conducting the windshear recovery and published missed approach procedure. This, in combination with an expectation that they would be turning left, contributed to them mishearing the ATC instruction to turn right. As a result, the aircraft was turned left. In addition, the flight crew omitted information from their readback and ATC did not correct the flight crew’s incomplete readback, which was a missed opportunity to correct the misheard instruction.
What has been done as a result
Singapore Airlines issued a notice to flight crew, highlighting strategies to manage high workload situations, as well as reiterating the importance of correct readbacks and acknowledgement from ATC.
Safety message
Compliance with ATC published procedures, such as readback procedures, provides assurance that instructions are correctly understood, which is especially important during high workload periods and/or in times of high traffic density. This incident highlights the importance of flight crew completing full readbacks, as well as controllers correcting any readback discrepancies immediately.
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