RIO DE JANEIRO - Investigators trying to determine why Air France Flight 447 broke apart in a violent storm over the Atlantic are looking at the possibility speed sensors - or an external instrument key to collecting speed data - failed in unusual weather, two aviation industry officials said Thursday.
Brazil's Navy issued a statement saying wreckage recovered by a helicopter crew earlier in the day was not from the doomed Airbus A330 that went down off the country's northeastern coast, killing all 228 people aboard - the world's worst aviation disaster since 2001.
With the crucial "black box" voice and data recorders still missing, investigators are relying heavily on the plane's automated messages to help reconstruct what happened. France's accident investigation agency said only two findings have been established so far: One is that the series of automatic messages sent from Flight 447 gave conflicting signals about the plane's speed; the other is that the flight path went through dangerously stormy weather.
Two officials with knowledge of the investigation told The Associated Press they are looking at the possibility an external probe that measures air pressure may have iced over. The probe feeds data used to calculate air speed and altitude to onboard computers. Other experts outside the investigation said it is more likely that sensors inside the aircraft that read the data malfunctioned.
If the instruments were not accurately reporting information, it is possible the jet would have been traveling too fast or too slow as it entered turbulence from towering bands of thunderstorms, according to the officials. Jetliners need to fly at just the right speed when encountering violent weather, experts say - too fast and they run the risk of breaking apart. Too slow, and they could lose control.
The French daily Le Monde, citing people close to the investigation, said the plane had been flying at "insufficient speed" before the crash and that Airbus was set to issue advice to companies using the A330 aircraft of optimal speeds during poor weather conditions.
Meteorologists said the Air France jet entered an unusual storm with 100 mph updrafts that acted as a vacuum, sucking water up from the ocean. The incredibly moist air rushed up to the plane's high altitude, where it quickly froze in minus-40 degree temperatures. The updrafts also would have created dangerous turbulence.