PARIS-- The flight recorders from an Air France plane that crashed nearly two years ago show that the captain only arrived in the cockpit after the plane had begun its fateful 3 1/2-minute descent, officials said Friday.
The initial findings of the French air accident investigation agency, the BEA, based on a reading of the black boxes recovered from the ocean depths, found that the captain had been resting when the emergency began.
All 228 aboard the Rio de Janeiro to Paris flight were killed on June 1, 2009.
"At the time of the event, the two co-pilots were seated in the cockpit and the captain was resting," a BEA statement says. The captain returned to the cockpit about 1 1/2 minutes after the autopilot disengaged at 2:10 a.m. and 5 seconds, Coordinated Universal Time, equivalent to GMT but more precise.
Reacting to wildly fluctuating airspeed indications and apparently confused by repeated stall warnings, pilots of an Air France jetliner in 2009 continued to pull the nose up sharply—contrary to standard procedure—even as the Airbus A330 plummeted toward the Atlantic Ocean, according to information released Friday by French accident investigators.
The long-awaited factual report, though it doesn't include any formal conclusions about the cause of the June 2009 crash that killed 228 people, provides details about a prolonged stall that lasted more than three and a half minutes. Throughout the descent, according to the report, "inputs made by the [pilot flying] were mainly nose-up" and the "angle of attack," or the position of the longitudinal axis of the plane in relation to the airflow "remained above 35 degrees."
If an airplane has entered an aerodynamic stall, which means its wings have lost necessary lift to remain airborne, from their earliest training pilots are taught to immediately push the nose down to regain speed, lift and maneuverability
The report also paints a somewhat unflattering picture of a seemingly confused cockpit, with the crew making extreme inputs to their flight controls and the engines spooling up to full power and later the thrust levers being pulled back to idle. At one point, according to the report, both pilots sitting in front of the controls tried to put in simultaneous commands.
The senior captain of the flight, who was on a routine rest break in the cabin when the trouble started, rushed back to the cockpit and was present during a large portion of the descent.
Air France praised the three pilots, who "demonstrated a totally professional attitude and were committed to carrying out their task to the very end," the airline said in a statement.
The carrier, a unit of Air France-KLM SA, noted that "the initial problem was the failure of the speed probes which led to the disconnection of the autopilot and the loss of the associated piloting protection systems."
Similar speed probes, known as pitot tubes, were known to face icing problems. Airbus and regulators had established procedures to handle such situations. The Air France pilots apparently didn't follow those procedures.
Airbus, a unit of European Aeronautics Defence & Space Co., said in a statement that it "is committed to continuing to provide support to the BEA investigation with the objective of identifying all potential lessons to be learnt."
About two minutes after the plane's autopilot and automated thrust controls kicked off due to the airspeed-indicator problems, the pilots were manually controlling the twin-engine jet as the wings rocked from side to side, the report reveals
"I don't have any more indications," one of the pilots said, referring to airspeed, "we have no valid indications." At that moment, according to the report, the thrust levers were pulled back to idle.
The report also said that both engines were operating and responding normally to pilot commands.
About a minute before impact, the report indicates "simultaneous inputs by both pilots on the sidesticks" that control the aircraft, with one of the pilots trying to clear up the confusion by telling the other "go ahead, you have the controls."
Pilots are trained to avoid such simultaneous commands.