Pilots did not clarify control after SriLankan A330 inadvertently pushed into descent

Investigators believe a SriLankan Airlines Airbus A330-300 lost considerable altitude during an in-flight upset after one of the pilots nudged the sidestick during cruise, disconnecting the autopilot and pushing the jet into a descent. While the inquiry does not specify the reason for the “sharp nose-down input” by the first officer, who was flying, it refers to his being served a meal, but not handing control of the aircraft to the other pilot – a cruise pilot in the left-hand seat who was standing in for the resting captain. The aircraft had been cruising at 39,000ft over the Indian Ocean, west of Jakarta, during a service from Colombo to Sydney on 21 March last year. Some 3h into the flight the captain went to rest in the cabin, and the cruise pilot moved from the right-hand seat to the captain’s left-hand seat. He acted as the monitoring pilot, while a relief first officer took over as flying pilot in the right-hand seat. The incident occurred a few minutes after the changeover. Analysis shows the first officer’s sidestick deflected nose-down for several seconds, sufficient to trigger involuntary disconnection of the autopilot and generate a master warning. The twinjet transitioned from 2.8° nose-up pitch to 1.1° nose-down and began to descend. Story has full details.<br/>