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French investigators say data from the two flight recorders retrieved from the wreckage of the Air New Zealand Airbus A320 that crashed into the Mediterranean has been recovered but it may be weeks before they can say what happened.
The Bureau d'Enquetes et d'Analyses pour la Securite de l'Aviation Civile, the French agency responsible for the probe, said data from the cockpit voice recorder and the digital flight data recorder had been retrieved at the manufacturers of the so-called black boxes, Honeywell in the United States.
"Work undertaken in the recorder manufacturer's laboratories, with the participation of specialised investigators from the BEA and the [American National Transportation Safety Board] made it possible to recover the data from the two recorders' memory cards," it said.
Investigators at the BEA - the Office of Inquiry and Analysis for Civil Aviation Safety - at Le Bourget on the northern outskirts of Paris are working alongside New Zealand and German investigators as well as officials from the NTSB and Airbus Industrie.
Information teased from the memory cards could give vital clues to the final moments of the A320, which crashed on November 27 while it was on acceptance trials.
The plane was due to be handed back to Air New Zealand after it had been leased by the German company XL Airways for two years. The cockpit voice recorder registers the conversations on the flight deck, while the digital flight data recorder contains technical records of the aircraft, including speed, altitude and trajectory.
In all, the flight recorder monitors 88 parameters such as flap position and autopilot mode. It also records such details as smoke alarms that can be a potent source of information.
An official at the BEA told the Weekend Herald that the agency was striving to produce a preliminary report but warned against unrealistic time pressures.
"Right now we are working hard to issue a preliminary report in the coming weeks, we cannot say exactly when because it takes time," the official said.
"It's a very complex issue examining and analysing everything, this takes time."
Investigators are likely to meet in Paris next week to take stock of the investigation.
In the days after the crash, French judicial investigators warned the black boxes had been so badly damaged they were unlikely to yield much insight.
Seven men including five New Zealanders were killed when the twin-engined airliner crashed off the coast of Perpignan, southwestern France. Only six bodies have been recovered from the wreckage, which is buried in mud some 40m under the sea. Experts at the Forensic Research Department in Montpellier are expected to meet judicial officials on January 13 to review the body identification process.
