Addis Ababa, Ethiopia - French aviation experts began work Friday on the heavily damaged data and voice recorders from Ethiopian Airlines flight 302, the airline said, while new revelations have suggested new links with an earlier crash in Indonesia involving the same type of aircraft.
The two so-called "black boxes" arrived at France's Bureau d'Enquêtes et d'Analyses, which has extensive experience analysing crashes, on Thursday. Germany had earlier turned down the opportunity to examine the recorders.
The data extracted from the recorders will be used to reconstruct the six-minute flight before the Boeing 737 Max 8 crashed into a farm field about 40 miles from Addis Ababa, killing all 157 passengers and crew, including the voice communication of the pilots and the readings of the various sensors.
The crash of another Max 8 aircraft into the Java Sea last October has been attributed in a preliminary investigation to a faulty sensor causing an automated system to push the nose of the plane down. The possibility that the same scenario occurred in Ethiopia has prompted precautionary groundings of the plane all over the world.
Bloomberg and several other media outlets cited investigators in the United States saying a device that sets the aircraft's trim was found in the wreckage and it was in position to force the airplane down - another similarity with the Indonesian crash.
Preliminary flight data showed an aircraft in trouble almost immediately and struggling to gain altitude in the high thin air above the Addis Ababa airport. The plane descended and then sharply ascended, while moving at speeds far in excess of normal.
Within minutes the pilot radioed the control tower and reported "flight control" problems and was given clearance to return.
A description of the exchange reported by the New York Times describes Capt. Yared Getachew speaking in a panicky voice as he requested to return shortly before losing contact.
In the case of the Lion Air flight in Indonesia, faulty information from the angle of attack sensor convinced the automated system that the plane was going to stall and pushed its nose down while the pilots wrestled to pull the aircraft up. The result was an erratic flight path that descended and ascended repeatedly before plunging into the ocean.
The data from the recorders would help determine if the potential links between the two crashes are real and related to this automated feature on the craft - hundreds of which were flown around the world until China started the trend to ground them on Monday.
The recorders are required on all flights in the world and are built to withstand fire, heavy impact and intense water pressure. It usually takes a month for investigators to come up with a comprehensive analysis of the data.
Because the country of origin of the aircraft is the United States, the National Transportation Safety Board will be involved in the investigation and has sent a team to Paris, in addition to its three investigators already in Ethiopia.
The Washington Post