Boeing urged to review 737 Max flight control system

Ethio­pian authorities on Thursday urged US aerospace giant Boeing to review the flight control system of its 737 Max 8 aircraft, which they say contributed to the March 10 crash that killed all 157 on board.

Ethio­pian Minister of Transport Dagmawit Moges gave a summary and the recommendations of a preliminary report into the crash in which she singled out the "aircraft flight control system" as contributing to the plane's difficulty in gaining altitude from Addis Ababa airport before crashing six minutes later.

The preliminary report has not been published yet, but could be released by the end of the week, the BBC reported.

"Since repetitive uncommanded aircraft nose-down conditions were noticed in this preliminary investigation, it is recommended the aircraft flight control system related to flight controllability be reviewed by the manufacturer," she said in a press conference here.

She said that "pilots repeatedly followed procedures recommended by Boeing before the crash, but despite their efforts were not able to control the aircraft".

It was the second crash of a Boeing 737 Max aircraft in five months. In October, Lion Air flight JT 610 crashed into the sea near Indonesia, killing all 189 people on board.

Like the Lion Air crash, attention in the Ethio­pian Airlines crash has been zeroing in on the Manoeuvering Characteristics Augmentation System (MCAS) -- a flight control system which pushes the nose of the aircraft down to avoid a mid-air stall.

While Moges didn't mention the MCAS by name, her comments suggested that the system was activated during the flight and the pilots were not able to use Boeing's recommended methods to disable it.

Investigators believe MCAS also contributed to the crash in Indonesia, where they say erroneous data from an outside sensor led the system to force the nose of the plane down over and over again, reports say.

In a statement, Ethiopian Airlines' Chief Executive Tewolde GebreMariam said he was "very proud" of the pilots' "high level of professional performance".

"It was very unfortunate they could not recover the airplane from the persistence of nosediving," the airline said in a statement.

Ethio­pian Airlines stated following the press conference that the report showed no fault lay with the pilots who "followed the Boeing recommended and Federal Aviation Administration-approved emergency procedures".

Both flights struggled to gain altitude and appeared to have erratic flight paths before crashing, reports say.

Amid reports that a foreign object might have damaged one of the Ethio­pian plane's sensors on takeoff, Amdeye Ayalew, the head of the investigation, said information from the recovered data recorders did not indicate that.

"We did not find any information regarding the foreign object damage on the aircraft," he said. "Is there a structural design problem? No, we cannot verify that now."

The 737 Max family of aircraft was grounded following the Ethiopian Airlines crash, a move affecting more than 370 planes worldwide.

Boeing said it "will be reviewing the published report as it is released".

--IANS

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