This photo provided by France's air accident investigation agency, the BEA, shows the flight data recorder from the 2009 Air France flight that went down in the mid-Atlantic. All 228 people aboard died after the aircraft plunged into the ocean. BEA, Johann Peschel/Associated PressFrance's air accident investigation agency says an undersea search has located the flight data recorder from the 2009 Air France flight that went down in the mid-Atlantic.

In a statement, the BEA said the so-called black box was "localized and identified" on Sunday morning. The statement included photos of the recorder — a cylinder partially buried in sand on the sea floor.

Investigators hope the recorder will help determine what caused the June 1, 2009, crash of Flight 447 from Rio de Janeiro to Paris. The data and voice recorders, though coloured dark orange, are referred to as "black boxes."

All 228 people aboard were killed when the aircraft plunged into a remote area of the Atlantic during a thunderstorm.

BEA officials have warned that the recordings may yet prove unusable, considering the pressure they were subjected to for two years.

"We can't say in advance that we're going to be able to read it until it's been opened," a BEA spokeswoman.

The flight data recorder stores technical data from the flight. Another so-called black box records cockpit conversations. The second black box has not yet been found, but the submarine probes were continuing, the spokeswoman said.

Manslaughter ruling against Airbus

The latest search marks a fourth attempt at locating the flight and data recorders. While parts of the plane have been recovered, wreckage containing the flight data recorders had never been found til now. The Air France plane crashed into deep waters, beyond the reach of radar and sonar, off the northeast coast of Brazil on June 1, 2009. CBC

The plane crashed into deep waters, beyond the range of radar and sonar. To conduct the actual search, planes and ships rely on sonar signals from the black box. Depths reach as far down as 3,900 metres in the Atlantic.

Automatic messages sent by the Airbus 330's computers showed it was receiving false air speed readings from sensors known as pitot tubes. Investigators have said the crash was likely caused by a series of problems, and not just sensor error.

Discovery of the black box is crucial as a French judge recently handed down a decision allowing preliminary manslaughter charges against Airbus, which made the plane. Information from the black box could help or hurt Airbus, the world's largest airplane manufacturer.

The $12.5-million US search was jointly financed by the airline and Airbus.

The search covered a 10,000-square kilometre area, several hundred kilometres off Brazil's northeast coast.

More than $28 million has been spent on previous searches.