FAA temporarily grounds Boeing 737-9 planes after panel blows out mid-flight

The FAA has ordered the immediate grounding of Boeing 737-9 Max jetliners a day after a piece of fuselage blew out of an Alaska Airlines plane mid-flight and forced an emergency landing in Portland, Oregon. 

The Federal Aviation Administration made the announcement on social media on Saturday, saying it will affect about 171 planes worldwide. 

Dramatic photos first shared by FOX 12 Oregon showed a a large piece of fuselage missing after the emergency landing. 

The Boeing 737-9 plane took off from Portland Friday afternoon with 174 passengers and six crew members on board and climbed to 16,000 feet before turning around, flight data showed. A passenger on the plane told FOX 12 he heard a "really loud bang" just as the plane reached cruising altitude, prompting the oxygen masks to drop. 

Photo of the Alaska Airlines plane after a window blew out mid-flight and forced an emergency landing in Portland, Oregon. (KPTV)

Another passenger said a kid's shirt was sucked off of his back and out of the plane, and other people on the plane had their phones and belongings fly out when the panel blew. 

One of the pilots declared an emergency and asked for clearance to descend to 10,000 feet (3 kilometers), the altitude where the air would have enough oxygen to breathe safely.

'We need to turn back to Portland," the pilot told controllers in a calm voice that she maintained throughout the landing process.

Videos posted by passengers online showed a gaping hole where the panel had been and passengers wearing their masks. They applauded when the plane landed safely about 13 minutes after the window blew out. Firefighters then came down the aisle, asking passengers to remain in their seats as they treated the injured.

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Miraculously, no one was seriously hurt. The Port of Portland told FOX 12 the fire department responded and treated minor injuries at the scene. One person was taken for more treatment but wasn't seriously hurt.

Alaska Airlines CEO Ben Minicucci announced Friday night that Alaska was grounding its 737-9 fleet until they could all be inspected. The 65 jets make up a fifth of the company's 314 planes. 

Even the short grounding disrupted the airline and its passengers. On Saturday, Alaska canceled more than 100 flights, or 15% of its schedule, by late morning on the West Coast, according to FlightAware.

Alaska said later on Saturday that the affected areas on 18 of the 737-9s so far were inspected during recent, intense maintenance work and were cleared to return to carrying passengers. 

"We are working with Boeing and regulators to understand what occurred ... and will share updates as more information is available," Minicucci said. "My heart goes out to those who were on this flight – I am so sorry for what you experienced."

Missing window shown after Alaska Airlines plane makes emergency landing (KPTV)

The plane involved rolled off the assembly line and received its certification just two months ago, according to online FAA records. The plane had been on 145 flights since entering commercial service on Nov. 11, said FlightRadar24, another tracking service. The flight from Portland was the aircraft's third of the day.

The Max is the newest version of Boeing’s venerable 737, a twin-engine, single-aisle plane frequently used on U.S. domestic flights. The plane went into service in May 2017.

United Airlines said Saturday it had inspected 33 of its 79 Max 9s, and pulling the planes from service had caused about 60 canceled flights.

Meanwhile, the union representing flight attendants at 19 airlines, including Alaska Airlines, commended the crew for keeping passengers safe.

"Flight Attendants are trained for emergencies and we work every flight for aviation safety first and foremost," the Association of Flight Attendants said in a statement Saturday.

Max deliveries have been interrupted at times to fix manufacturing flaws. The company told airlines in December to inspect the planes for a possible loose bolt in the rudder-control system.

Boeing said it was aware of the incident, working to gather more information and ready to support the investigation.

The FAA and the National Transportation Safety Board said they would also investigate Friday's incident.

The Associated Press contributed to this report.