Preliminary data retrieved from the flight data recorder of the Ethiopian Airlines plane that crashed shows “a clear similarity” with an earlier crash in Indonesia, Ethiopia’s transport minister has said.
“The black box has been found in a good condition that enabled us to extract almost all the data inside,” Dagmawit Moges told reporters on Sunday evening.
The parallels would be the “subject of further study during the investigation”, with a preliminary report to be issued in “30 days”, she added.
Officials say 157 people from 35 different countries were killed when the Nairobi-bound plane crashed shortly after takeoff on March 11.
A number of countries and airlines have now grounded the Boeing 737 MAX 8s.
The company now faces the challenge of proving the jets are safe to fly amid suspicions that faulty sensors and software contributed to the two crashes that killed 346 people in less than six months.
The US Federal Aviation Administration (FAA) has already said satellite-based tracking data showed that the movements of Ethiopian Airlines Flight 302 were similar to those of Lion Air Flight 610, which crashed into the Java Sea off Indonesia in October, killing 189 people.
The planes in both crashes flew with erratic altitude changes that could indicate the pilots struggled to control the aircraft. Shortly after their takeoffs, both pilots reported flight control problems and tried to return to the airports but crashed.
In the case of the Ethiopian Airlines flight, the black boxes have been handed to France’s BEA air safety agency, which is working with US and Ethiopian investigators to determine what went wrong.
US officials said the FAA and US safety agency NTSB have not yet validated data from the black boxes.
Focus on sensor
The aircraft’s state-of-the-art Maneuvering Characteristics Augmentation System (MCAS) is under scrutiny. On the Lion Air flight, the initial accident investigation report indicated erroneous data from a sensor repeatedly triggered the anti-stall system and may have contributed to the crash.
The FAA said on Thursday that all 787 MAX planes would remain grounded until a software until a software upgrade to the MCAS could be tested and installed in all of the planes.
Boeing said the changes would include updates to the “flight control law, pilot displays, operation manuals and crew training”.
The Seattle Times reported on Sunday that the original safety analysis that Boeing gave to the FAA had ‘several crucial flaws’. The analyis helps the FAA certify a plane’s safety.
The report said the analysis understated the power of the system which could push the nose of the plane down, that it could reset itself after a pilot countered it, and that the consequences of it failure were mischaracterized, allowing MCAS to rely on data from a sole sensor.
The paper said: “Both Boeing and the FAA were informed of the specifics of this story and were asked for responses 11 days ago, before the second crash of a 737 MAX last Sunday.”
A Boeing spokesman said “(the) 737 MAX was certified in accordance with the identical FAA requirements and processes that have governed certification of all previous new airplanes and derivatives,” according to the Reuters news agency.
“The FAA concluded that MCAS on all 737 MAX met all certification and regulatory requirements.”