The so-called black boxes could hold the mystery as to why the plane plunged into the Atlantic Ocean [Reuters]

French investigators are preparing to open the flight recorders found from the wreckage of an Air France flight that plunged into the Atlantic Ocean two years ago, in an attempt to shed light on what caused the crash.

Jean-Paul Troadec, France's chief air accident investigator, said he was confident about recovering data from the devices, known as black boxes, adding that they appeared to be in good shape.

Investigators on Thursday displayed the two voice and data recorders in public for the first time since they were retrieved one week ago, after a search operation that cost $50m.

Families of the 228 people killed in the Rio-Paris plane crash in June 2009 are hoping that their wait for an explanation may soon be over.

Christophe Menez, head of the BEA crash investigation authority's engineering department, said it would take at least three days to learn whether information contained on the recorders could be retrieved.

Bodies found at site

"We have been waiting for 23 months, which is a long time," Robert Soulas, who lost his daughter and son-in-law in the crash, told the Reuters news agency.

"We were frustrated during these long months and we hope this is a new departure and things will move more rapidly."

Investigators will extract, clean and dry the seven memory cards in each data recorder, then test them to see if they work. If so, the data will be copied onto a computer.


The flight recorders could solve the mystery behind the crash, Al Jazeera's Paul Brennan reports

"If the card is in good shape it can be read in a couple hours,'' Menez said. If damaged, it is impossible to say how long it might take to try to cull information from it, he added.

Forensic experts from the French police force will also be examining tissue samples from two bodies found from the crash site earlier this month.

Some 50 bodies were found among the wreckage, but will only be brought up if investigators can extract DNA information to identify the first pair.

"If identification is impossible, we believe the respect accorded to the victims and yourselves demands the bodies remain in their last resting place," Jean Quintard, the French public prosecutor, told relatives.

Francois Daoust, the head of the French Forensic Institute, said the bodies had spent two years at 4,000 metres under the sea, under 400 bars of pressure, which may have rendered the DNA unusable.

The wreckage was discovered April 3 after nearly two years of searching a remote swathe of the mid-Atlantic between Brazil and West Africa.

Finding the cause took on new importance in March when a French judge filed preliminary manslaughter charges against Air France and the plane's manufacturer, Airbus.

Experts say the flight data and voice recorders are indispensable for determining what was at fault.

The accident was the worst disaster in Air France's history. The flight from Rio de Janeiro to Paris slammed into the Atlantic northeast of Brazil after running into an intense high-altitude thunderstorm.

Automatic messages sent by the Airbus 330's computers showed the aircraft was receiving false airspeed readings from sensors known as pitot tubes. 

Source: Agencies