The Australian Transport Safety Bureau (ATSB) today released a report on its investigation into AirAsia X flight 223 on March 10 last year that departed from Sydney and headed for Melbourne – instead of its intended destination, Kuala Lumpur.
The ATSB found that the captain inadvertently entered the wrong data into the flight computer.
“The captain got the longitudinal position of the aircraft incorrect by 11,000 kilometres, sending the A330’s on-board navigation system into a spin.
“Despite a number of opportunities to identify and correct the error, it was not noticed until after the aircraft became airborne and started tracking in the wrong direction,” the ATSB report said.
“The ATSB also found that the aircraft was not fitted with an upgraded flight management system that would have prevented the data entry error via either automated initialisation or automatic correction of manual errors.”
According to the ATSB report, Air Traffic Control (ATC) in Sydney was forced to hold up an aircraft on another runway when the AirAsia X plane turned towards its take off path.
The flight crew had attempted to “troubleshoot and rectify the situation while under heavy workload” but that only made the problem worse, the ATSB said.
“Combined with limited guidance from the available checklists, this resulted in further errors by the flight crew in the diagnosis and actioning of flight deck switches.”
The report also noted that the crew then elected to discontinue the flight but were unable to return to Sydney as the weather had deteriorated in the Sydney area and the available systems limited the flight to approaches in visual conditions.
The Sydney ATC came in for special praise from the ATSB for “reducing the risk to the aircraft and other aircraft in the area”.
“This occurrence highlights that even experienced flight crew are not immune from data entry errors,” the ATSB report said.
“However, carrying out procedures and incorporating equipment upgrades recommended by aircraft manufacturers will assist in preventing or detecting such errors.”
The investigation also followed up with measures taken by the airline since the incident occurred.
According to the ATSB, AirAsia X has since made a number of changes, including the development of a new training bulletin and package for flight crews.
As per international convention, AirAsia X also shared the lessons from its internal investigation with all pilots, and reviewed the recovery procedures required in the event of a similar occurrence.
AirAsia X currently flies from Kuala Lumpur to four Australian cities, namely Sydney, Melbourne, Perth and the Gold Coast. The airline started servicing the Australia route in 2007.