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10 Unsolved Airplane Mysteries

        Science | Modern

1
Was a Sleepy Pilot to Blame?
Brazilian Navy divers recover a huge part of the rudder of the Air France Airbus A330 out of the Atlantic Ocean, some 745 miles (1,200 km) northeast of Recife in 2009. © Brazilian Air Force/Handout/Xinhua Press/Corbis
Brazilian Navy divers recover a huge part of the rudder of the Air France Airbus A330 out of the Atlantic Ocean, some 745 miles (1,200 km) northeast of Recife in 2009. © Brazilian Air Force/Handout/Xinhua Press/Corbis

In an accident reminiscent of Malaysia Airlines Flight 370, Air France Flight 447 disappeared over a stretch of the ocean where there was no radar coverage. In June 2009, this Airbus A330-200 airliner carrying 216 passengers and 12 crew members disappeared over the Atlantic en route from Rio de Janeiro to Paris.

For several days, no one knew what had happened. But even after wreckage was spotted and recovered, the circumstances remained murky. The state-of-the-art jet was equipped with the latest tracking and communication equipment, yet it hadn't emitted a distress signal at any point. Two years later, the plane's black boxes were finally recovered from the ocean [source: Smith].

French air safety investigators concluded in a 2012 report that the tragedy likely had been caused by an odd cascade of errors. Ice crystals accumulated on a probe, causing it to give incorrect speed readings and the autopilot system to disengage. The aircraft's two co-pilots, who were in charge at the time because the captain was taking a break, apparently became confused by the malfunction. By the time the captain rejoined them 90 seconds later, the airplane already was in a stall that he could not avert. The plane crashed two minutes and thirty seconds later [source: BEA].

Why it took the captain so long to respond to the co-pilots' frantic calls for help has never been explained. News media reported that the captain was accompanied on the flight by a female companion, and that he'd only slept one hour the night before [sources: Battiste, Smith].