US Investigators at odds Over Ethiopian Crash Report

DALLAS - The United States National Transportation Safety Board (NTSB) has expressed their dissatisfaction over comments by Ethiopian investigators in their official report on the crash of Ethiopian Airlines flight ET302 on March 10, 2019, which killed 157 people.

The Ethiopian Aircraft Investigation Bureau released its much-delayed report on the crash on December 23. In it, the Bureau laid sole blame on "uncommanded" inputs by the aircraft's Manoeuvring Characteristics Augmentation System or MCAS. It said that a faulty angle-of-attack sensor caused MCAS to repeatedly pitch the aircraft's nose down, leading to loss of control.

Ethiopian received its first 737 MAX in July 2018. Photo: Boeing.

Possible Bird Strike?

However, the NTSB said that Ethiopian authorities ignored its findings that a bird strike could have damaged the sensor during the take-off run. Despite searches, the NTSB claims that the sensor was never found at the crash site. Ethiopian investigators, however, said in the report that they did not find any evidence of a bird strike.

US authorities also disagree with the Ethiopian inquiry's point that the Boeing airliner was "unrecoverable" by the pilots. In a statement, the NTSB said, "We believe that the probable cause also needs to acknowledge that appropriate crew management of the event, per the procedures that existed at the time, would have allowed the crew to recover the airplane even when faced with the uncommanded nose-down inputs."

"The flight crew's failure to reduce thrust manually and the excessive airspeed that resulted played a significant role in the accident sequence of events," it added.

The two crashes led to the type's global grounding for 20 months. Photo: Luca Flores/Airways.

"Confusing Alerts"

Despite being fully licensed and qualified to fly the aircraft under Ethiopian Civil Aviation Rules and Standards, the report found that the rapidly deteriorating situation in the flight deck and "confusing alerts" startled the flight crew. This subsequently affected their "situational awareness and ability to perceive each and everything to the detail."

ET flight 302 was the second crash involving the Boeing 737 MAX in five months. It led to a global grounding of the airliner, which exposed issues with the types MCAS system. After costing Boeing around US$20bn and denting the plane maker's reputation, the 737 MAX has bounced back, returning to service after 20 months and racking up countless new orders.

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Featured Image: ET Boeing 737-8 (ET-AXG). Photo: Michael Rodeback/Airways.