Addis Ababa (AFP)

Ethiopian investigators responsible for determining the causes of the crash of Ethiopian Airlines Boeing 737 MAX blamed in particular the "inadequate" training provided by the American aircraft manufacturer, in a progress report published Monday on the eve of the first anniversary of the catastrophe.

On March 10, 2019, six minutes after takeoff from Addis Ababa, flight ET302 bound for Nairobi had crashed in a field southeast of the Ethiopian capital, killing 157 passengers and crew instantly .

This accident occurred less than five months after that of an Indonesian airline Lion Air 737 MAX, which left 189 people dead in a few minutes after taking off from Jakarta.

The succession of the two tragedies plunged the American aircraft manufacturer into the worst crisis in its history.

It was mainly the malfunction of the MCAS anti-stall system, specially designed to compensate for the heavier engines of the 737 MAX, which was blamed in the two disasters.

In a preliminary report in April 2019, Ethiopian investigators pointed out that the pilots of flight ET302 had followed the procedures recommended by Boeing but were unable to regain control of the aircraft.

In their report released Monday, they say the design of the MCAS system "makes it vulnerable to unwanted activation." More specifically, the report highlights the fact that the system can be activated by only one of the aircraft's angle of attack sensors.

Thus, in the case of flight ET302, the Ethiopian investigators noted "shortly after take-off" an "incorrect" measurement of the angle of attack from the left side sensor.

This measurement automatically activated the MCAS system, which led to the nose dive several times.

- 'Shoot with me!' -

They also point out that the measurements of the aircraft's angle of attack differ between the left and right sensors, until the end of the on-board data recording, that is to say until the crash.

"We look forward to examining the full information and formal recommendations that will be contained in the Ethiopian Bureau of Investigation and Accident's final report," responded in a Boeing statement, which again extended its "sincere condolences" to the families and close to the victims of ET302.

The report also gives details of the latest exchanges between the two men in the cockpit. "Shoot with me!" directs pilot Yared Getachew to his co-pilot Ahmednur Mohammed as he tries to regain control of the 737 MAX and straighten the nose of the aircraft.

The latest flight measurements indicate that the aircraft was traveling at over 900 km / h and descending at over 33,000 feet per minute (10 km per minute).

The plane crashed into a field southeast of Addis Ababa, causing a crater 10 meters deep, "40 meters long and 28 meters wide". Debris from the aircraft was found hundreds of meters from the point of impact.

On Friday, the US Congressional Transportation Committee ruled that the Boeing 737 MAX was a "fundamentally faulty and dangerous" aircraft.

The 737 MAX has been grounded since March 13, 2019. Authorities around the world had made this rare decision due to the similarities between the Lion Air and Ethiopian Airlines disasters.

The giant in Seattle (northwest) has suspended deliveries, stopped production and replaced its managing director. This crisis is the most serious in 104 years of the history of the famous aircraft manufacturer.

Boeing is currently working on a fix for the MCAS system to obtain the lifting of the flight ban.

Relatives of the 157 victims, from more than 30 different countries, are expected to attend the crash site on Tuesday for an intimate ceremony.

On Sunday, hundreds of Ethiopians, mostly villagers living nearby, paid a moving tribute to the victims, women wearing white clothes over their black outfits to symbolize the end of the mourning period.

© 2020 AFP