Black boxes from the fatal Air France crash in 2009 revealed no new technical issues with the Airbus SAS A330 jet on first examination, investigators said Tuesday, but added that it was too soon to blame human error.
Analysis of voice and data recorders is "just beginning," France's BEA accident-investigation bureau said after Airbus told the airlines that preliminary findings did not yet warrant changes to equipment or operating guidance systems. After the crash, carriers had been told to switch speed sensors on the model.
Investigators said they had a complete set of data from the black boxes, recovered from the Atlantic Ocean and shipped to Paris this month after two years' immersion at 12,800 feet. The findings on Flight 447 come just weeks before the second anniversary of the June 1, 2009, crash, which killed 228 people en route from Brazil to Paris.
"The gathering of the entire cockpit audio and flight-perimeter data makes it almost certain that this accident will be fully explained," the BEA said. Airbus officials said separately that they had "no immediate recommendation" for A330 operators and promised updates when authorized to share more information.
Flight 447's last automated transmissions, minutes before the crash, suggested that faulty speed readings from devices known as pitot tubes could have caused the autopilot to shut down in bad weather, a situation pilots are trained to handle.
Investigators have said that faulty sensors could not by themselves have caused the crash and that an improper response to the readings or other unrelated elements would be required.
The absence of information on the flight's final minutes has so far hindered the investigation.