On Thursday, the US Civil Aviation Regulatory Agency (FAA) announced the opening of a formal investigation into a possible Boeing malfunction, which may have played a role in the 737 MAX 9's door stalling during an Alaska Airlines flight.
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The investigations must “determine whether Boeing failed to ensure that (the devices) conformed to the intended design and were capable of operating safely,” the FAA said in a news release.
The regulatory body that notified the manufacturer of the start of the investigation states that “Boeing’s methods must meet the highest standards to which it is legally bound.”
The FAA insisted that “this accident should never have happened and should never happen again,” noting that the 737 MAX 9 planes it had ordered to be inspected must remain on the ground until further notice.
The FAA investigation will be conducted in parallel with the NTSB investigation, which has been operating since Saturday.
On Friday, a door opened from the cabin of a Boeing 737 Max 9 during an Alaska Airlines flight heading from Portland, Oregon, to Ontario, California, but the accident caused only a few injuries and the plane was able to land safely at its original airport.
Boeing CEO Dave Calhoun pledged on Wednesday that the plane maker would determine “what went wrong in the original work that allowed this failure.”
During inspections already conducted since Saturday, the two largest customers of the 737 MAX 9, United Airlines and Alaska Airlines, both revealed the discovery of loose equipment in some of their planes.
Boeing suggests to its customers on MAX 9 aircraft that they lock certain doors when the number of emergency exits in place is already sufficient for the number of seats in the aircraft.
