Searchers find part of Air France black box off Brazil

Deep-sea searchers picking through wreckage of an Air France plane that crashed off Brazil in 2009 have found a part that held one of the flight's data recorders, but without the memory unit that could provide crucial clues to the crash.

France's BEA air accident inquiry office said in a statement that the chassis of the "black box" flight data recorder had been found surrounded by debris during the first dive by an underwater remote vehicle.

The Airbus 330-203 plane plunged into the Atlantic off the northeast coast of Brazil en route to Paris from Río de Janeiro in June 2009, killing all 228 passengers and crew on board after the flight hit stormy weather.

The recent discovery of chunks of the plane's wreckage, in a vast search radius of some 10,000 square kilometres (3,860 square miles), had raised hopes that the aircraft's two black boxes might be within reach.

A BEA spokeswoman told reporters that the flight data recorder could still be in a condition to be read, despite its separation from the chassis.

"The memory module is like a sarcophagus -- the information is very well protected," she said.

Speculation about what caused the accident has focused on the possible icing up of the aircraft's speed sensors, which seemed to give inconsistent readings before communication was lost.