On 27 May 2011, the BEA released an update on its investigation, describing the history of the flight as recorded by the flight data recorder. At 3 hour 55 minutes absolute time, the captain gave his seat to the 2nd co-pilot and went out of the cockpit to rest. At 4 hours 6 minutes absolute time, the pilot warned the cabin crew that they were about to enter an area of turbulence. 4 minutes later, the pilots turned the plane slightly to the left and decreased its speed to 0.8 Mach due to increased turbulence.
At 4 hours 10 minutes and 5 seconds absolute time, the autopilot and the auto-thrust systems disengaged. The pilot made a left nose-up input, as the plane began rolling to the right. The plane's stall warning sounded twice. 10 seconds later, the plane's recorded airspeed dropped sharply from 275 knots to 60 knots. The plane's angle of attack increased, and the plane started to climb. The left-side instruments then recorded a sharp rise in airspeed to 215 knots. This change was not displayed by the Integrated Standby Instrument System until a minute later (the right-side instruments were not recorded). The pilot continued making nose-up inputs, and at around 4 hours 11 minutes into the flight, the plane had climbed to its maximum altitude of around 38,000 feet. There, its angle of attack was 16 degrees. At 4 hours 11 minutes 40 seconds, the captain re-entered the cockpit. The angle of attack had then reached 40 degrees, and the plane had descended to 35,000 feet.
The stall warnings stopped, as all airspeed indications were now considered invalid due to the high angle of attack. Roughly 20 seconds later, the pilot decreased the plane's pitch slightly, air speed indications became valid and the stall warning sounded again. From there until the end of the flight, the angle of attack never dropped below 35 degrees.
The recordings stopped at 4 hours 14 minutes and 28 seconds absolute time. At that point, the plane's ground speed was 107 knots, and it was descending at 10,912 feet per minute. During its descent the plane had turned more than 180 degrees to the right to a compass heading of 170 degrees. The plane was stalled during its entire 3 minute 30 second descent from 38,000 feet.
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