A runway excursion involving a Mandarin Airlines ATR 72-600 in Taiwan on 22 August 2018 was due largely to the flight crew’s non-compliance with operating procedures.
The aircraft, registered B-16852, was operating flight AE788 from Magong Airport (now known as Penghu Airport) to Taichung Airport, when it veered off the runway during a rainy landing.
The excursion, which took place at about 19:28 local time, damaged the underside of the fuselage and three runway lights. No injuries were recorded among the 70 passengers and four crew.
Investigations by the Taiwan Transportation Safety Board indicate that the flight crew had failed to follow Mandarin Airlines’ flight operations manual for landing.
In its final investigation report, it found that during approach, the 42-year-old first officer took control of the turboprop, even though the visibility at that time did not meet the prescribed minimum for first officers.
The first officer disengaged autopilot at about 19:27 at an altitude of 240ft. At this moment they observed that the rain intensify, and had sighted the runway.
The 60-year-old captain then told his first officer that the aircraft’s approach was deviating to the left. The first officer tried to use the rudder to guide the aircraft back to the centre line, but investigations indicate that he was unable to do so, with visibility affected by the heavier downpour.
When the aircraft landed it was still angled to the left. Only then did the captain take control. It was, however, too late, and the ATR 72 veered off the runway.
The board said that the crew also did not undertake a proper risk assessment, even though they were aware of thunderstorms in the area before they took off from Penghu Airport. The board notes there was no examination of “possible risk increasing to approach landing due to threats of heavy rain, thunderstorms and low visibility.”
It has recommended that Mandarin Airlines ensure its flight crew perform operations according to the relevant manuals and standards, with these to be enforced by the Civil Aeronautics Administration (CAA).
Cirium’s Fleets Analyzer indicates that the aircraft has operated with Mandarin since December 2017. After the incident, it was taken out of service for two months for repair, and resumed flying in October 2018.
The board also found that the edges of Taichung Airport’s runway contain potholes and vertical concrete structures. This increases the chance of damage in the event of a runway excursion.
It suggested the installation of runway centre lights that would help pilots align to the centerline. This is especially so since runway edge lights were more than 50m apart, it notes.