Air France Flight 447Monday June 1, 2009
The Airbus went missing over the Atlantic Ocean on a flight from Rio de Janeiro to Paris, France. The plane departed from Rio de Janeiro-Galeao International Airport at 19:03 LT bound for Charles de Gaulle Airport in Paris. The last radio contact with the flight was at 01:33 UTC. The aircraft left CINDACTA III radar coverage at 01:48 UTC, flying normally at FL350. The aircraft reportedly went through a thunderstorm with strong turbulence at 02:00 UTC. At 02:14 UTC an automated message was received indicating a failure of the electrical system. The plane carried 12 crew members and 216 passengers. The wreckage was finally discovered on April 3, 2011 using unmanned submarines. Flight447 passed into clouds associated with a large system of thunderstorms, its speed sensors became iced over, and the autopilot disengaged. In the ensuing confusion, the pilots lost control of the airplane because they reacted incorrectly to the loss of instrumentation and then seemed unable to comprehend the nature of the problems they had caused. Neither weather nor malfunction doomed flight, nor a complex chain of error, but a simple but persistent mistake on the part of one of the pilots.
The crew did not realize the plane was in a stall, were insufficiently trained in flying manually, and never informed the passengers that anything was wrong before they plunged into the sea. The captain was on a rest break when the warnings began. The two co-pilots were facing faulty speed readings from unreliable sensors and repeated alarm signals, but fail to explain why the pilots responded the way they did. It's unclear why the co-pilot at the controls maintained a nose-up input - contrary to the normal procedure to come out of an aerodynamic stall. Normally, the nose should be pointed slightly downward to regain lift in such a stall, often caused because the plane is traveling too slowly. A basic maneuver for stall recovery, which pilots are taught at the outset of their flight training, is to push the yoke forward and apply full throttle to lower the nose of the plane and build up speed. The report confirms that external speed sensors obstructed by ice crystals produced irregular speed readings on the plane. Since the accident, Air France has replaced the speed monitors on all its Airbus A330 and A340 aircraft. The BEA said neither of the co-pilots at the controls had received recent training for manual aircraft handling, or had any high-altitude schooling in case of unreliable air speed readings. A stall warning sounded numerous times, and once for a full 54 seconds, but the crew made no reference to it in cockpit exchanges before the jet crashed.