The Air France jet which crashed into the Atlantic en route from Rio in 2009 stalled and fell in three and a half minutes, French investigators report.
The air accident investigations bureau found the crew were faced with contradictory speed readings just before the plane crashed.
At the time, the captain was taking a routine rest, with the two co-pilots in control in the cockpit.
The BEA statement did not look at the causes of the crash. All 228 people on board were killed in the disaster.
The BEA findings were released in an online statement in response to speculation in the media over the findings from the flight recorders, only recovered from the sea this month.
A full report into the disaster is not expected until next year.
Air France said on Friday that it appeared “the initial problem was the failure of the speed probes”.
Since the crash, the air line has replaced the speed, or Pitot, probes on its Airbus fleet with a newer model.