A preliminary report on the crashed Ethiopian Airlines flight will be issued in 30 days—but officials in Addis Ababa already believe there are resemblances with the October Lion Air crash in Indonesia.
Ethiopian transport minister Dagmawit Moges on Sunday (March 17) said an initial analysis of the black boxes recovered from the wreckage showed “clear similarities” between the two crashes. The Lion Air plane crashed into the sea minutes after departing Jakarta in late October, killing all 189 people on board. On March 10, the Nairobi-bound Ethiopian flight plunged outside Addis Ababa minutes after takeoff, killing all 157 people.
Both crashes involved the Boeing 737 Max 8, leading aviation authorities across the world to ground the model last week. Since then, questions have swirled around the safety of the widely-used aircraft and especially of its automated anti-stalling system. Known as the Maneuvering Characteristics Augmentation System (MCAS), the feature was incorporated to direct the nose of the plane downwards if it is in danger of stalling. Both the Ethiopian and Lion Air planes hit trouble just after takeoff, with pilots reporting flight control challenges and controllers observing steep oscillations.
Dagmawit didn’t further outline how the two crashes were analogous but said the similarities would be the “subject of further study during the investigation.” Ethiopian CEO Tewolde GebreMariam shared similar sentiments last week. The US Federal Aviation Administration last week said that “refined” satellite data and physical evidence from the site of the Ethiopian crash pointed to similarities between the two accidents.

Concern over the 737 Max model has wiped billions of dollars off Boeing’s market value as the company faces increasing scrutiny and probes. On Sunday, the Seattle Times, citing current and former FAA and Boeing engineers, reported Boeing’s safety analysis of the MCAS had several crucial flaws. These included failure to account for how the system could reset itself each time a pilot responded; in addition, by the time the plane came into use, the automated feature could move the tail more than four times further than what was recorded in the initial safety analysis document.
The Seattle Times also said it contacted both Boeing and the US Federal Aviation Administration with the specifics of the story 11 days ago, or roughly four days before the Ethiopian Airlines crash. The FAA told the paper last Friday it was “unable to delve into any detailed inquiries” while Boeing noted it had it “met all certification and regulatory requirements.”
The US Department of Transportation is also investigating Boeing‘s development of the 737 Max, with a grand jury in Washington DC issuing a subpoena for documents related to the commercial aircraft, according to the Wall Street Journal. The department is also seeking to determine if the FAA used appropriate methods to approve the commercial jetliner’s MCAS system. Boeing declined to comment on the investigation as reported by the WSJ.
As the potential problems with the automated system have arisen, the issue of pilot training has come into focus too. When the plane was first introduced, Boeing and the FAA agreed pilots who had flown a related earlier 737 model didn’t need additional simulator training, nor training specifically about MCAS. Pilots qualified to fly the 737-800 only received training that amounted to “an iPad lesson for an hour.” Since the Lion Air crash, pilots have received formal instruction on the feature, pilot unions have said.
Boeing on Sunday said it was finalizing the development of a software upgrade and pilot training revision that will address the MCAS flight control in its 737 Max planes.
Read more of Quartz’s coverage of the Boeing 737 Max crisis.