French accident investigators will publish a second interim report in December on the crash of Air France Flight 447 from Brazil to France, a spokeswoman for the investigators said Monday.
The report will contain investigators' findings on weather conditions, the flight's automatic maintenance messages and an analysis of "incoherent speed readings" from other flights, said Martine Del Bono, a spokeswoman for France's accident investigation agency BEA.
Investigators still do not know what caused the crash in June, which killed all 228 people aboard.
The Airbus A330 jet was flying from Rio de Janeiro to Paris when it went down in the Atlantic Ocean, 930 miles (1,500 kilometers) off Brazil's mainland and out of radar coverage.
The BEA released its first set of preliminary findings in July, saying the accident represents one of history's most challenging plane crash investigations. The probe, which has operated without access to the plane's flight data and voice recorders, appears so far to have unveiled little about what really caused the accident.
The agency hopes to be prepared to launch a third search phase for the plane's black boxes by the middle of January, Del Bono said, reiterating comments by BEA director Jean-Paul Troadec.
The BEA's first report into the crash said faulty readings by speed sensors, called Pitot tubes, were an element but not the cause of the crash.
