The first Alaska Airlines passenger flight on a Boeing 737-9 Max airplane takes off on a flight to San Diego from Seattle-Tacoma International Airport in Seattle on March 1, 2021.

Caption

The first Alaska Airlines passenger flight on a Boeing 737-9 Max airplane takes off on a flight to San Diego from Seattle-Tacoma International Airport in Seattle on March 1, 2021. / AP

Updated January 6, 2024 at 10:31 PM ET

The Federal Aviation Administration on Saturday ordered the grounding and immediate inspection of about 171 Boeing 737 Max 9 aircraft worldwide after a mid-flight emergency late Friday involving one of the planes operated by Alaska Airlines.

"The FAA is requiring immediate inspections of certain Boeing 737 MAX 9 planes before they can return to flight," the agency's administrator Mike Whitaker said in a statement.

The decision comes after an Alaska Airlines flight was forced to abruptly land in Portland, Ore., on Friday night after a door plug blew out in mid air, leaving a hole in the aircraft next to two unoccupied seats.

In a news conference on Saturday night, National Transportation Safety Board (NTSB) Chair Jennifer Homendy said: "We are very, very fortunate here that this didn't end up in something more tragic... No one was seated in 26A and 26B, where that door plug is." The NTSB is also investigating the incident.

Homendy added that the accident would could have led to more severe outcomes if the plane had been at its cruising altitude of 35,000 feet, with people standing or walking to use a restroom, but thankfully the flight was "only 10 minutes out from the airport when the door blew".

She said that no passengers sustained serious injuries, but some on board were treated for minor injuries. Despite that, for people on board, the accident must have been "truly terrifying," she said, as the blowout resulted in rapid decompression of the cabin.

Authorities were still searching for the door plug, which is thought to have fallen and landed in the community of Cedar Hills, about 7 miles west of central Portland. Homendy urged anyone who found it to contact local police.

On Friday night, Alaska Airlines grounded and ordered a fleet-wide inspection of its Boeing 737 Max 9 aircraft. On Saturday, United Airlines said it would temporarily ground all 79 of its Boeing 737 Max 9 planes to conduct inspections mandated by the FAA.

Southwest Airlines and American Airlines told NPR they do not carry Boeing 737 Max 9s. While they do carry Boeing 737 Max 8s, both airlines said the model does not raise any concerns.

"The MAX -8 aircraft in our existing fleet and the -7 in our future fleet do not have the exit door plug involved in the Friday evening event. Our fleet and operation are unaffected," a Southwest spokesperson said in a statement.

Meanwhile, India's aviation regulator ordered the immediate inspections of all Boeing Max 737 aircraft owned by domestic operators, Reuters reported. None of India's air operators are believed to carry the model that abruptly landed in Portland on Friday.

The incident comes less than four years after Boeing Max aircraft were allowed to fly passengers in the U.S. All Boeing Max planes were grounded worldwide in 2019 after two deadly crashes involving Max 8 jets.

In December, Boeing urged airlines to check their 737 Max jets for loose bolts after the discovery of at least two planes with improperly tightened nuts.

In a statement, Boeing spokesperson Jessica Kowal said the company supports the FAA's call for inspections.

"Safety is our top priority and we deeply regret the impact this event has had on our customers and their passengers," Kowal said. "In addition, a Boeing technical team is supporting the NTSB's investigation into last night's event. We will remain in close contact with our regulator and customers."

What happened Friday night

Alaska Airlines Flight 1282 took off from Portland, Ore., shortly after 5 p.m. PST Friday, bound for Ontario, Calif. After the incident, social media posts showed a gaping hole on the plane's left side.

Oxygen masks were deployed as the aircraft quickly returned to Portland International Airport at 5:26 p.m. PST, according to FlightAware.com. The flight had 171 passengers and six crew members on board. No casualties or serious injuries were reported.

KPTV reported that the local fire department arrived on scene and treated minor injuries. At least one person needed further medical attention.

"We are working with Boeing and regulators to understand what occurred tonight, and will share updates as more information is available," Alaska Airlines CEO Ben Minicucci said in a statement.

The airline grounded all of its Boeing 737 Max 9 aircraft late Friday until it could inspect each plane. On Saturday, Alaska Airlines said it had completed inspections for more than a quarter of its planes and there were "no concerning findings."

The company added that it will return planes to service after their inspections are completed "with our full confidence." The airline expects inspections on all 65 of its Boeing 737 Max 9s to be completed in the next few days.

Boeing 737 Max's troubled history

The aircraft's safety problems were under global scrutiny after deadly crashes in Indonesia in 2018 and Ethiopia in 2019 — which killed a total of 346 people. After a worldwide halt in 2019, Boeing 737 Max completed its first U.S. commercial flight in December 2020.

Investigators determined that the company's newly rolled-out flight control system was partly to blame. In both incidents, the system known as MCAS acted on a faulty sensor and forced both planes to erroneously nosedive even as the pilots attempted to regain control.

But it wasn't just manufacturing flaws. A report by the Department of Transportation's inspector general found that the company failed to tell regulators about critical changes it made to its flight control system. The report concluded that Boeing did this in order to expedite the plane's certification process.

In 2021, Boeing agreed to pay more than $2.5 billion to settle a criminal charge related to the crashes. Under the deal, Boeing was ordered to pay a criminal penalty of $243.6 million while $500 million went toward a fund for the families whose loved ones were killed in the crashes. Much of the rest of the settlement was marked off for airlines that had purchased the troubled 737 Max planes.

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