The Airbus A320 jet plunged into the Java Sea while en
route from Surabaya, Indonesia, to Singapore on Dec. 28, killing all 162
people on board.
It had been suffering maintenance faults with a key flight control
computer for over a week, and one person familiar with the matter said
the captain had flown on the same plane with the intermittently faulty
device just days before the crash.AirAsia said it
would not comment while the matter was under investigation by the
National Transportation Safety Committee (NTSC) of Indonesia.
The maintenance problems on the Flight Augmentation Computer (FAC), and the way the pilots reacted to them, were at the heart of the investigation.
After trying to reset this device, pilots pulled a circuit-breaker to cut its power. People familiar with the matter said it was the Indonesian captain Iriyanto who took this step, rather than his less experienced French co-pilot Remy Plesel, who was flying the plane.
The outage would not directly upset the aircraft but would remove flight envelope protection, which prevents a pilot from taking a plane beyond its safety limits, leaving the junior pilot to fly the jet manually in delicate high altitude conditions.
The decision to cut off the FAC has surprised people following the investigation because the usual procedure for resetting it is to press a button on the overhead panel.
Lawyers for the family of the French co-pilot say they have filed a lawsuit against AirAsia in Paris for “endangering the lives of others” by flying the route without official authorisation on that day. Investigators have said the accident was not related to the permit issue.
AirAsia did not immediately respond to requests for comment on the lawsuit.
Although more is becoming known about the chain of events, people familiar with the investigation warned against making assumptions on the accident's cause, which needed more analysis.
The maintenance problems on the Flight Augmentation Computer (FAC), and the way the pilots reacted to them, were at the heart of the investigation.
After trying to reset this device, pilots pulled a circuit-breaker to cut its power. People familiar with the matter said it was the Indonesian captain Iriyanto who took this step, rather than his less experienced French co-pilot Remy Plesel, who was flying the plane.
The outage would not directly upset the aircraft but would remove flight envelope protection, which prevents a pilot from taking a plane beyond its safety limits, leaving the junior pilot to fly the jet manually in delicate high altitude conditions.
The decision to cut off the FAC has surprised people following the investigation because the usual procedure for resetting it is to press a button on the overhead panel.
Lawyers for the family of the French co-pilot say they have filed a lawsuit against AirAsia in Paris for “endangering the lives of others” by flying the route without official authorisation on that day. Investigators have said the accident was not related to the permit issue.
AirAsia did not immediately respond to requests for comment on the lawsuit.
Although more is becoming known about the chain of events, people familiar with the investigation warned against making assumptions on the accident's cause, which needed more analysis.
Safety experts say air crashes are most often caused by a
chain of events, each of which is necessary but not sufficient to
explain the underlying causes of the accident.