An AirAsiaX flight from Sydney to Malaysia ended up in Melbourne instead, after a crew navigational error made the plane’s computer think it was somewhere over southern Africa, about 11,000 kilometres from where it actually was.
The error, according to Australia’s Air Transport Safety Bureau (ATSB), happened when the plane’s captain accidentally omitted a zero while entering the plane’s longitude, causing an error of about 11,000 kilometres.
The incident occurred on 10 March 205 and the ATSB report has just been released. The plane, an A330, took off from Sydney but ran into problems with the onboard navigation systems.
As the ATSB put it: “Attempts to troubleshoot and rectify the problem resulted in further degradation of the navigation system, as well as to the aircraft’s flight guidance and flight control systems. The crew 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 aircraft was instead radar vectored to Melbourne, Victoria and the flight completed in visual conditions.”
The ATSB found that when setting up the aircraft’s flight management and guidance system, the captain inadvertently entered the wrong longitudinal position of the aircraft.
“This adversely affected the onboard navigation systems however, 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 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.
“The flight crew attempted to troubleshoot and rectify the situation while under heavy workload. 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 ATSB said.
“Finally, the ATSB identified that effective monitoring and assistance by air traffic control reduced the risk to the occurrence aircraft and other aircraft in the area.”
AirAsia X subsequently acted to fix the problem, including:
- Developing of a training bulletin and package for its flight crews that emphasised the correct operation and alignment of the air data and inertial reference system.
- Sharing the lessons learnt from the operator’s internal investigation with all pilots and reviewing the recovery procedures to be undertaken in the form of a flight safety notice.
The airline issued a statement yesterday, carried by AirlineRatings.com, in which it stressed that all AirAsia X aircraft had been equipped with upgraded flight management systems since the incident.
“AirAsia X would like to stress that we have in place robust management systems to monitor and prevent similar incidents from reoccurring,” the statement said.
Written by Peter Needham