The BEA has released a precis of the data contained on AF447’s flight data recorder and with the data so provided we can now look into the cockpit of AF447 in those last minutes of flight as the pilots battled to save their aircraft.
The BEA’s report in general supports my tentative theory that the pilots, presented with confusing and inconsistent information misinterpreted the situation and as a result inadvertently placed the aircraft into a deep stall.
This post is part of the Airbus aircraft family and system safety thread.
More specifically we now know that:
- the aircraft did not break up in a storm,
- the aircraft was responsive to control inputs up until it hit the sea,
- the accident commenced with an unreliable airspeed event,
- there was an initial high speed climb as the TCAS ACARS implied,
- the pilots did not carry out the unreliable air speed QRH,
- pilot inputs after the initial climb placed and maintained the aircraft in a high alpha (stall) state,
- As the cabin vertical speed ACARS implied the aircraft hit the sea at greater than 10,000 fpm.
While there are still open issues from the BEA report, such as the THS trimming to 13 degrees, it appears the danger that the pilots faced was not a tropical storm or failing aircraft but their own perceptions of the situation.