The preliminary evaluation of the flight data recorders from the crashed Ethiopian Airlines aircraft is still not officially available. But the Wall Street Journal is currently reporting new details from the last minutes before the crash on March 10, citing a person familiar with the investigation. According to this, after the occurrence of problems on their flight, the pilots initially followed emergency instructions from Boeing. Later, however, they deviated from this checklist and had an electronic system to stabilize their Boeing 737 Max 8 back on. Then it came to crash.
The machine was finally pitched on the ground six minutes after the start in the Ethiopian capital Addis Ababa. 157 people from over 30 nations died. Just five months earlier, in October 2018, a Boeing of the same type had crashed in Indonesia shortly after take-off. The crash of the Lion Air machine cost 189 lives.
Wheels for manual control have to be turned many times
Shortly after the crash of Ethiopian Airlines, the MCAS trim system was under suspicion. MCAS is supposed to prevent pilots from accidentally pulling the nose of the aircraft up so high that it causes a dangerous stall on the wings. If the aircraft rises too steeply, the technology automatically engages in the height control and lowers the nose.
It was already known that the MCAS system was active at the time of the crash of the Ethiopian Airlines machine. However, the "Wall Street Journal" now writes that it should have been switched off at least temporarily before. The pilots had deactivated the electronics immediately after take-off and instead tried to trim the plane by hand. Aircraft manufacturer Boeing initially did not want to comment on the matter, according to a report by the Reuters news agency.
Software update is delayed
For manual trim there are wheels with cranks in the cockpit, on the side of the pilot and the co-pilot. However, they have to be rotated many times to achieve the desired effect.
This procedure would also correspond to the emergency instructions that Boeing had published after the Lion Air crash. However, according to the newspaper, the electronics had apparently been switched on again later. The crew would have deviated from the checklist. The reasons for this are currently unknown. The report, however, relies on experts in government and industry, according to which the manual intervention of the pilots apparently did not bring the desired results.
According to investigators, Reuters reports that the MCAS system had been turned on up to four times before the crash of Ethiopian Airlines. But it is not clear whether the crew is responsible for each of these four times.
Boeing has been working on a software update for the MCAS system over the past few weeks. The intention is to persuade the air traffic control authorities to give the Boeing 737 Max a new take-off license. Currently, around 350 aircraft of this type worldwide have to remain on the ground, only transfer flights without passengers are allowed. Most recently, however, it became apparent that the approval of the software solution might take several weeks.