Ethiopia has begun examining cockpit voice and flight data recordings from doomed Ethiopian Airlines flight 302 and is working with U.S., EU and French experts, the Ministry of Transport said on Thursday.

The ministry gave no date for when a preliminary report on the analysis of the so-called black boxes would be released, saying only it would be done in line with the standards of the Montreal-based International Civil Aviation Organization.

All 157 people on board were killed when the pilots lost control of the new Boeing 737 MAX 8 plane shortly after take-off from Addis Ababa on March 10 and crashed.

The disaster echoed a similar crash in Indonesia in October involving the same plane model that killed all 189 people on board. It prompted aviation authorities around the world to ground Boeing MAX aircraft, including more than 300 of the MAX 8 type.

A U.S. team led by the National Transportation Safety Board (NTSB), as well as experts from France's Air Accident Investigation Agency (BEA) and the European Union Aviation Safety Agency (EASA) are helping analyse the black boxes, the Ethiopian ministry said.

They will work with the Accident Prevention and Investigation Bureau of Ethiopia, it said.

Their findings will be important for the families of the victims, the airline, and for Boeing, which has a backlog of orders worth more than $500 billion for the MAX series, its fastest selling model.

Ethiopian Airlines, a well-established and dominant player across Africa, has been a longstanding and loyal Boeing customer, buying its first planes from the U.S. manufacturer in 1962.