French navy zeroes in on Rio-Paris air crash black boxes
The French navy has closed in on the black boxes of an Air France jet that crashed in the Atlantic nearly a year ago, officials said Thursday, raising hopes that light will be shed on the disaster that left 228 dead.
French officials cautioned however that this breakthrough did not mean that the black box flight recorders will be successfully retrieved from the ocean floor.
"It's like trying to find a shoe box in an area the size of Paris, at a depth of 3,000 metres (9,800 feet) and in a terrain as rugged as the Alps," said navy spokesman Hugues du Plessis d'Argentre.
The flight recorders have been localised within three nautical miles (five kilometres) in an area 200 nautical miles northwest of the Brazilian archipelago of Sao Pedro and Sao Paulo, the navy said.
Flight 447 was en route to Paris from Rio de Janeiro when it went down on June 1 in stormy weather, killing all 228 people on board.
The crash was the worst in Air France's 75-year-history.
Intensive but unsuccessful sweeps of the Atlantic Ocean using submarines equipped with deep-sea sonar had turned up some debris but no sign of the flight data and cockpit recorders.
The black boxes are key to understanding what caused the disaster, which remains largely unexplained.
The breakthrough in pinpointing the zone came after new computer software was used to decode data collected by deep-sea submarines during their search in June and July last year, said the defence ministry.
At that time, the black boxes were still emitting a signal.
Experts from the French electronics firm Thales made the discovery when they were called in to help decypher data from the sonar of the Emeraude submarine.
"We found three sounds that are compatible with the signals emitted by the black boxes, given their frequency, their duration and the various technical parameters," said a Thales spokesman.
"These are the type of signals that come from black boxes," he said.
The French Navy started a new operation on Monday to find the black boxes.
Welcoming the news, the families of the crash victims said it raised hopes but they quickly added that they would hold off on any celebration until the flight recorders were raised to the surface.
"This is a sign of hope, it's very good news for the families after 11 months of waiting," said Jean-Baptiste Audousset, president of an association grouping the families of some 60 victims.
Government spokesman Luc Chatel added: "We must remain extremely cautious because at this time we are talking about an area where they have been located."
"We then have to see if it is possible to recover the black boxes, depending on the depth, the surface area to cover... So I remain extremely cautious," Chatel told France Info radio.
The latest search effort was set to wrap up on May 25, but officials said it may be extended again following the new findings.
The French air accident agency BEA has said that the jet's speed probes, made by French firm Thales, gave false readings and were "one of the factors" in the crash but "not the sole cause".
Pilots' unions and some of the relatives of victims of June's crash have accused Air France and Airbus of ignoring longstanding problems with air speed monitors on its jets in the run up to the disaster.
The companies insist that their jets met all safety standards, but they have nevertheless now replaced the speed monitors made by Thales with a different model produced by US firm Goodrich.
© 2010 AFP