alaska airline
© Getty Images / Mario Tama/Getty ImagesAn Alaska Airlines plane takes off from Los Angeles International Airport (LAX) on December 4, 2023 in Los Angeles, California
Alaska Airlines has said it is "temporarily" grounding its fleet of Boeing 737 Max-9 planes after one of them lost a window and a section of the fuselage in mid-air on Friday, forcing an emergency landing in the US state of Oregon.

The airline said the jet, which was carrying 174 passengers and six crewmembers, landed safely after it returned to Portland, 35 minutes into a scheduled flight to California. Flight tracking data indicated that the aircraft had reached an altitude of 16,000ft (4876m) before it began its emergency descent.

"Alaska Airlines flight 1282 from Portland, Oregon, to Ontario, California, experienced an incident this evening soon after departure," the company said late on Friday. It added that it had taken the step of "temporarily grounding" its fleet of 65 Boeing Max-9 planes until a full investigation is completed.

The Max-9 is the latest of Boeing's 737 series of twin-engine, single-aisle planes. The aircraft, which went into service in May 2017, is frequently used in US domestic flights.

Images posted to social media from inside the stricken airliner show a gaping hole in its left side, behind the wing and engine. Others show the seat closest to the affected area, which was apparently unoccupied, having been damaged in the incident.

"My heart goes out to those who were on this flight," Alaska Airlines CEO Ben Minicucci said in the statement issued by the airline on Friday night. "I am so sorry for what you experienced." He added that he was "grateful for the response of our pilots and flight attendants."

Boeing said it had been made aware of the incident and was "working to gather more information," and that it had a technical team standing by to support an investigation. The Federal Aviation Administration, meanwhile, confirmed that the aircraft had reported a pressurization problem and that it had launched an investigation.

The Boeing 737 Max series has been described as "the most scrutinised transport aircraft in history" following a series of investigations into its safety, particularly after the Max was grounded for 18 months in March 2019 following two crashes in 2018 and 2019, that killed a total of 346 people.

In order to resume operations, each Max aircraft underwent significant safety modifications. Around 1,300 Boeing 737 Max-9 planes are thought to be currently in operation, according to data from the manufacturer.