France's BEA air crash investigation agency said yesterday it had managed to transfer all the information stored in devices hauled from the seabed two weeks ago.
This is the most important breakthrough yet in efforts to find out what caused the crash.
The BEA brought forward its target date for publishing a new report on the crash by around six months and said it may be able to issue interim findings in the summer.
Paul Hayes, safety director UK-based aviation consultancy Ascend Aviation, said: "The most interesting thing will be to find out what the crew were seeing and understanding and how they were reacting and managing their responses."
Flight 447 from Rio de Janeiro to Paris went missing and crashed in a storm on 1 June, 2009. The black boxes were found earlier this month, and brought nearly 2.5 miles to the sea's surface after a search operation costing $50 million. They arrived in Paris on Thursday.
The successful data transfer includes all information from the flight data recorder, which monitors aircraft systems, and a loop containing the last two hours of cockpit voice recordings.
The BEA said in a statement: "This (analysis] work will take several weeks, after which a further interim report will be written and then published during the summer."
Investigators had earlier said any information gleaned from the black boxes would take months to process and that they did not expect to issue a report until early in 2012.