Incident Overview
On 26 December 2014, an Airbus A330 operated by XL Airways departed from La Réunion (Indian Ocean) en route to Marseille, France. During the flight, the information provided by the three inertial reference systems became successively unavailable. This caused the autopilot and auto-thrust to disconnect, and the aircraft lost attitude and navigation information.
Crew Response
The flight crew responded by diverting the aircraft to Athens, Greece. They used backup instruments and flight controls in direct law to navigate and control the aircraft. The landing was uneventful, and weather conditions at the time were reported as good.
Investigation
The incident is being investigated by the Bureau d'Enquêtes et d'Analyses pour la sécurité de l'aviation civile (BEA). The National Transportation Safety Board (NTSB) has been appointed an Accredited Representative to assist the BEA in the investigation, as the United States is the state of design of the Air Data Inertial Reference Unit (ADIRU). All inquiries concerning this incident should be directed to the BEA.