(Reuters) – Ethiopia's investigators urged Boeing Co. reviewing his flight control technology and said pilots of the state-owned Ethiopian Airlines had performed correct procedures in the first public results of the crash of a 737 MAX jet that killed 157 people.
The convicted flight was repeatedly reached when the pilots struggled to control the almost full aircraft before it crashed six minutes after the launch of Addis Ababa under clear conditions, Ethiopian authorities said on Thursday.
"The crew performed all procedures Transport Minister Dagmawit Moges told a news conference that presented the outlines in a preliminary report.
Investigators are expected to publish the report by Friday.
Boeing's top sales aircraft have grounded the world since the disaster on March 1
The families of the victims, regulators and travelers around the world have been waiting for signs of whether the two crashes are linked and extended as the Boeing technology and actions of the Ethiopian airlines' pilots played a role.  Ethiopian investigators did not accuse anyone of the crash, in line with international rules requiring civilian probes focus on technical recommendations for safer f Nor did they provide a detailed analysis of the flight, which is expected to take several months before a final report is calculated within one year.
However, in a clear indication of where Ethiopian investigators control the regulators' attention, they cleared the pilots of using erroneous procedures and issued two safety recommendations aimed at the newly introduced aircraft.
They suggested that Boeing review the air traffic control system and that the aviation authorities confirm any changes before allowing the model of the plane back in the air.
"As repetitive, indeterminate aircraft nos down conditions are noticed … it is recommended that the aircraft control system be reviewed by the manufacturer," says Mrs. Dagmawit.
Nos-down commands were issued by Boeing's so-called MCAS software. The preliminary report to the Lion Air disaster suggested that pilots lost control after checking with MCAS, a new automated anti-stall feature that repeatedly lowered the nose of the aircraft based on erroneous sensor data.
The US Federal Aviation Administration, which has been branded over the way it decided to certify the MCAS software, warned the investigation had not yet been completed.
"We continue to work for a complete understanding of all aspects of this accident. When we learn more about the accident and the results become available, we will take appropriate action," said the US agency in a statement.
Boeing said It would study the report when it was released.
Ethiopian Airlines said its crew had followed all the proper guidance to deal with a severe emergency.
However, the report could kick a debate with Boeing on how the crew responded to issues triggered by inaccurate data from an air flow sensor, especially if they cleaned the plan before they shut down the main program.
Questions about the pilot having planned the plane before connecting MCAS and how many times MCAS was activated were not answered at a press conference that lasted about 40 minutes 19659002] Following a previous Ethiopian Airlines accident from Beirut in 2010 the authorities of Addis Ababa said the conclusions of a Lebanese inquiry citing pilot errors and suggested that the aircraft had exploded D into a possible sabotage action.
Officials rejected reports of tensions between Ethiopian officials and the United States and other foreign investigators accredited for the current probe.
"We have no reservations from various stakeholders who were involved in investigations," says chief investigator Amdye Ayalew Fanta.
Aviation security analyst Paul Hayes said that a deeper investigation would appear in the role played by software and how pilots could react and said he hoped scars from the 2010 dispute would not get in the way of a comprehensive investigation.
"Pilots should not have to cope with such an emergency. We need to understand what are the factors that meant that these two crews were overcome, says Mr. Hayes, security manager at UK-based consultancy Flight Ascend.
"It is unusual that there is one thing," he added.
On Wednesday, Boeing said it had successfully tested an update of the MCAS software designed to make it easier to handle.