27/08/2025
Successful wind shear escape, SAAB 340 turboprop.
An ATSB occurrence brief details a windshear escape involving a Saab 340, near Sydney Airport.
--What happened--
On the evening of 6 July 2025, a Saab 340 was being used to conduct a scheduled air transport flight to Sydney Airport, New South Wales. On board were 2 flight crew, 1 cabin crew and 27 passengers. The captain reported that the weather around Sydney at the time included developed thunderstorms and that holding and diversions had been in effect. They further reported that arrivals had recently been resumed as storms had passed and that, on final approach, weather radar indicated that the nearest storm cell was no closer than 19 km to the north.
When the aircraft was about 19 km west of Sydney, the automatic terminal information system (ATIS)[1] was revised to advise that the wind had increased from 20 kt from the west to include gusts of up to 40 kt. Consequently, air traffic control (ATC) changed the active runway to runway 25.[2] The aircraft was the second to be sequenced for an approach to the revised runway, following an Airbus A320. Passing about 14 km from the airport on final approach, the Saab crew heard a broadcast from the A320 crew that they were conducting a windshear escape[3].
At the time, the A320 was approximately 9 km ahead. Hearing that the preceding aircraft had encountered windshear, the Saab crew discussed their windshear escape procedure and decided to continue the approach, waiting to hear more details about the nature of the windshear.
Approximately 2 minutes later, ATC advised the Saab crew that the A320 had encountered severe undershoot windshear.[4] The crew assessed that they were passing the position the A320 had first detected the windshear at this time. Shortly afterwards, when at approximately 700–800 ft, the captain reported that they observed a decrease in airspeed and an abnormal power indication consistent with windshear. The captain called for a windshear escape which the crew initiated. Throughout the subsequent climbing manoeuvre, they conducted a series of power, airspeed and configuration changes until confident they were no longer affected by windshear.
Two subsequent aircraft landed on runway 25 without any further reported windshear encounters, after which arriving aircraft were again sequenced for runways 34L/34R. Following the windshear escape, the aircraft was re-sequenced for runway 34L and landed without further incident.
--Safety message--
Low-level windshear is a serious threat to the safety of departing and landing aircraft. If windshear is encountered, rapid and large control inputs may be required and in severe cases, the effect of windshear may exceed the performance capabilities of the aircraft. Flight crew should use all available indicators to avoid areas of known windshear on the intended flight path. These include the presence of thunderstorm cells, and reports from pilots of other aircraft and air traffic control.
[1] Automatic terminal information service: the provision of current, routine information to arriving and departing aircraft by means of continuous and repetitive broadcasts. ATIS information is updated either routinely or when there is a significant change to weather and/or operations.
[2] Runway number: the number represents the magnetic heading of the runway. The runway identification may include L or R as required for left or right when there are parallel runways.
[3] Windshear: a change in wind speed and/or direction over a short distance. A windshear escape is a pilot recovery technique used when an inadvertent windshear encounter is experienced.
[4] Undershoot windshear: a rapid decrease in the headwind component of the wind.
--About this report--
Decisions regarding whether to conduct an investigation, and the scope of an investigation, are based on many factors, including the level of safety benefit likely to be obtained from an investigation. For this occurrence, no investigation has been conducted and the ATSB did not verify the accuracy of the information. A brief description has been written using information supplied in the notification and any follow-up information in order to produce a short summary report, and allow for greater industry awareness of potential safety issues and possible safety actions.
