An Air France plane that crashed in the Atlantic between Brazil and West Africa, killing all 228 people on board, hit the ocean intact, investigators say.
A month-long probe into the June 1 disaster also found that defective air speed monitors on the Airbus A330 were “a factor but not the cause” of the crash, the worst in Air France’s history.
“The plane was not destroyed while in flight,” said Alain Bouillard from the BEA accident investigation agency as it released its first report on the loss of Flight 447 from Rio de Janiero to Paris.
“The plane appears to have hit the surface of the water in flying position with a strong vertical acceleration,” he said, adding that the Airbus came down in the water belly-first.
“The plane was intact at the time of impact,” Bouillard told a news conference at BEA headquarters in Le Bourget outside Paris.
There had been speculation that problems with the Airbus’ airspeed sensors, or pitot tubes, may have caused the plane to stall or fly dangerously fast, causing a high-altitude breakup.
Cause of crash still unclear
But investigators said that they had ruled out a mid-air breakup after carefully examining the 640 pieces of debris that have been recovered from the crash zone hundreds of kilometres off Brazil’s coast.
The airliner’s fin was discovered still attached to part of its base structure, further strengthening the view that the plane was all in one piece when it hit the water.
No inflated life jackets were found among the debris, said Bouillard, adding that “the passengers were obviously not prepared for an emergency sea landing.”
The lead investigator said the air speed sensors were “one of the factors but it’s not the only one” that led to the crash as the plane flew through turbulence.
“It’s a factor but not the cause.
“We are still some distance away from establishing the causes of the accident,” he said.
Inconsistent speed data
French investigators have focused on the air speed sensors which fed inconsistent readings to the cockpit shortly before it plunged into the Atlantic.
No distress call was received from the pilots, but there was a series of 24 automated messages sent by the plane in the final minutes of the doomed flight, investigators say.
The BEA, along with Airbus and Air France, have repeatedly said there is as yet no firm evidence linking the speed monitors to the crash of the jetliner.
Air France nevertheless has upgraded all sensors on its long-haul fleet as a precautionary measure after protests from pilots.
The BEA was reporting on its first findings even though an intensive deep-sea search for the plane’s flight recorders has yet to yield results.
Brazil decided on June 27 to call off the recovery operation but France has maintained its nuclear submarine, research vessel and other boats in the area on a final hunt for the black boxes.
Flight recorders still missing
The BEA has decided to continue the search for the flight recorders until July 10.
The homing beacons on the flight recorders emit signals for about one month after the crash and the BEA hopes that they will have a longer-than-usual shelf life.
French investigators complained that they had yet to see the results of autopsies being performed on the 51 bodies pulled from the disaster area, despite formal requests to Brazilian authorities.
The pilots of Flight 447 also failed to connect to the flight control center in Dakar, Senegal after leaving Brazil’s zone, which meant that search and rescue operations could have been launched earlier, Bouillard said.
People from 32 different countries — including 72 French citizens and 59 Brazilians — were aboard the Airbus A330 when it came down.