FAA investigating Boeing after Alaska Airlines door blows off in-flight

The U.S. Federal Aviation Administration says it is investigating Boeing after a door on a MAX 9 aircraft blew out during an Alaska Airlines flight.

“This incident should have never happened and it cannot happen again,” the FAA said in a statement.

The FAA formally notified Boeing it is conducting an investigation to determine if Boeing “failed to ensure completed products conformed to its approved design and were in a condition for safe operation in compliance with FAA regulations.”

The FAA said that the investigation is a result of the Boeing 737 MAX 9 plane losing a “plug”-type passenger door.

The incident occurred Friday night shortly after takeoff when a plane was about 16,000 feet in the air above Oregon and a plug covering an unused exit door blew off, causing oxygen masks to be deployed and a child’s clothing to reportedly be sucked off.

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The plane returned safely to Portland International Airport about 20 minutes after takeoff with its 174 passengers and six crew members unharmed.

The FAA has since ordered all 171 MAX 9s operating in the U.S. to be grounded for inspection.

United Airlines said Monday that it found loose bolts and other installation issues in the door plugs of Boeing 737 MAX 9 planes during inspections that were triggered due to the incident. United operates 79 MAX 9s.

“This is one of my worst fears,” John Gradek, an aviation management expert who teaches at McGill University, told Global News in an interview after news of the loose bolts finding.

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“The best-case scenario … was that the incident on Friday was a one-off and isolated, and that all the other 737 Max 9s would pass inspection with flying colours. That does not seem to be the case.”

— with files from Global News’ Sean Boynton.