Search teams trying to locate the flight recorders from Air France flight AF447 have located the flight-data recorder, but not the critical memory unit.
The chassis of the recorder was located during the first dive operation by a remote underwater vehicle, the Remora 6000, after a recovery vessel arrived in the crash zone yesterday.
France's Bureau d'Enquetes et d'Analyses states that the chassis of the flight-data recorder has been found on the sea bed "surrounded by debris from other parts of the airplane".
But the BEA adds that the crucial crash-survivable memory unit - in which the data from the aircraft's instruments is stored - was not attached.
There is no indication of the whereabouts of the cockpit-voice recorder.
Flight AF447 from Rio de Janeiro to Paris crashed in the South Atlantic on 1 June 2009, sparking a two-year hunt for the Airbus A330-200's wreckage.