The This was when the pilot used the

The flight 447 departed from Rio de Janeiro at 22:29 UTC scheduled to
arrive in Paris at 09:03 UTC. The last contact of the aircraft with land was at
01:35 UTC. At around 02:06 UTC, the aircraft entered the area of the thunderstorm
and was having a constant turbulence. After passing through the storm for 2 to
3 minutes, the aircraft experienced the icing conditions and anti-icing system
of the craft came on. This was also when the ice crystals also started to block
the pitot tubes. At 02:10 UTC, the auto-pilot system of the aircraft turned off
because the correct readings of the air speed were not being received anymore
as by this time the pitot tubes had been completely covered and blocked by ice
crystals. Due to the shut down of auto-pilot system of the aircraft, the auto-thrust
system disengaged as well and the aircraft started to move left because of the turbulence.
This was when the pilot used the side stick to control the aircraft and keep it
steady. For the next 30 seconds, the aircraft moved from left to right and the
pilot also brought the aircraft in the nose-uplift position which was unnecessary
in that situation. At the same moment, the aircraft stall warning started sounding
due to the angle of attack exceeding the limit of tolerance. The pilot kept the
nose up position of the craft for the next 30 seconds and with the speed that
he was at, the aircraft was climbing with 7000 feet a minute. The left-side
instrument had also malfunctioned and was giving incorrect readings of the
aircrafts speed showing a sharp increase in the speed. At 02:11 UTC, the
aircraft had reached the maximum allowed altitude for an Airbus A330. At that
moment the angle of attack was 16 degrees but as the aircraft started
descending the angle of attack reached to 30 degrees. At this moment, the stall
protection system was not working either. Hence, the lift was lost by the wings
and the aircraft stalled. 

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