Pilots on an Albany-bound flight that had to turn around and return to Perth were overloaded with tasks after caution lights lit up, causing them to not notice a big reduction in air speed that could have made the plane stall.
The Australian Transport Safety Bureau deemed the incident on a Regional Express flight on July 6 “serious”, but fortunately, the aircraft carrying 16 passengers landed safely.
During the climb, flight crew were alerted to a fault in the turboprop’s wing de-ice system, which they couldn’t clear after levelling off.
They began descending to get below conditions where icing may form and decided to return to Perth.
But during a turn, warning of a potential stall was activated.
Recorded data showed engine power had been reduced from 60 per cent torque to about 15 per cent during descent — remaining there when the plane was levelling off and turning.
“The pilot flying became task saturated due to high workload and did not notice the aircraft’s reducing airspeed, which was also missed by the pilot monitoring due to a focus on other tasks,” the ATSB’s Stuart Macleod said.
The heavy workload included multiple communications with air traffic control, the ATSB said.
Regional Express amended crew training to include flight at minimum manoeuvring speeds instructions.