Air France crash: What is known so far
Two weeks after the flight disappeared, investigators have pieced together many clues but still need the black boxes.
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- The rudder limiter reported problems. The rudder limiter prevents pilots from turning the tail rudder too wildly at high speeds – an act that could shear the entire rear stabilizer off the plane.Skip to next paragraph
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This, in particular, is a curious clue, because the rear stabilizer has been found torn from the plane – the very thing the computer was trying to prevent.
- The primary, secondary, and flight-management computers failed.
The Times of London reports that a similar "incoherent cocktail of alarms" occurred six times on Air France flights since February 2008. Though pilots eventually regained control in those instances, one situation became so dire that the pilot issued a mayday call. In each case, the emergency appeared to be linked to Pitot tubes that malfunctioned in stormy weather, The Times concludes.
The French Bureau of Investigations and Analyses, however, has refused to blame the Pitot sensors. Experts, too, caution against inferring a certain line of cause and effect while so much crucial information is still unknown.
What appears clear, though, is that the trouble mounted quickly. Flight 447's pilots made no mayday or emergency transmission, and photos of the crew's seats show them folded, meaning the crew had not yet returned to them in response to an emergency.
Also increasingly apparent is that the flight was not downed by a bomb. The bodies recovered so far have had no burns or shrapnel.
The recovery. As of Sunday, 49 bodies had been recovered. The search for the black boxes was mounting. But the challenge is enormous. After a 2004 plane crash off the coast of Egypt, authorities needed two weeks to recover the black boxes, even though the crash was relatively close to shore.
"This time, the sea floor is more than 4,000 meters [13,000 feet] deep in some areas, and the ocean bed is described as extremely varied in depth," notes Aviation Week.