An emergency landing on Friday of an Alaska Airlines Boeing 737 Max 9 jet in Portland, Ore., led the Federal Aviation Administration to order some U.S. airlines to stop using some Max 9 planes until they are inspected. The order affects about 171 planes owned by Alaska, United and other airlines. The episode also raised troubling new questions about the safety of a workhorse aircraft design dogged by years of problems and multiple deadly crashes.
No one was seriously injured in Friday’s incident. The jetliner returned to the airport in Portland shortly after a chunk of the body of the plane broke off in midair, leaving a door-size hole in the side of the aircraft.
Within hours of the episode, Alaska Airlines said it would ground all 65 of the Boeing 737 Max 9 aircraft in its fleet until mechanics could carefully inspect each plane. Later on Saturday, the F.A.A. ordered the temporary grounding of planes in some other airlines’ fleets. United Airlines, with 79 Max 9s, had the most planes affected.
Late Saturday, Jennifer Homendy, chairwoman of the National Safety Transportation Board, the body in charge of investigating airplane crashes, said that a plug on one of the unneeded emergency doors on the plane tore off 10 minutes out from the airport while the plane was at an altitude of about 16,000 feet.
Ms. Homendy said the investigators would be comparing the plug on a second emergency door, on the opposite end of the aisle, with the one that had blown out in hopes of determining what went wrong. She added that investigators would also be looking at things like the pressurization system and the plane’s maintenance records.
Jessica Kowal, a spokeswoman for Boeing, said in a statement, “We agree with and fully support the F.A.A.’s decision to require immediate inspections of 737-9 airplanes with the same configuration as the affected airplane.”
And while the particular issue that led to Friday’s scare appeared unique, Boeing’s 737 Max airliners have perhaps the most worrisome history of any modern jetliner currently in service.
What happened on Friday?
Alaska Airlines Flight 1282, which was carrying 171 passengers and six crew members bound for Ontario, Calif., made an emergency landing at the Portland airport on Friday evening 20 minutes after takeoff.
Passengers on the flight reported hearing a loud sound before noticing that a section of the fuselage had opened up in midair.
In the minutes preceding the emergency landing, with oxygen masks dangling from the ceiling and the wind howling through the gaping hole in the wall, passengers could not hear urgent announcements made over the public address system.
The plane involved in Friday’s incident was virtually new by commercial airline standards. It had been first registered in November and had logged only 145 flights.
What’s the history of the 737 Max?
Two crashes involving Boeing 737 Max 8 aircraft killed a total of 346 people in less than five months in 2018 and 2019. Both crashes were later associated with a malfunctioning system that overrode pilot commands.
Those crashes led to a global grounding of Boeing 737 Max planes, parking hundreds of aircraft on tarmacs around the world for nearly two years while engineers worked to identify and solve the problem so that regulators could recertify the planes.
The first crash took place in October 2018, when a jetliner carrying 189 people from Jakarta, Indonesia, plummeted into the Java Sea only minutes after takeoff. Four months later, another 737 Max, this one flown by Ethiopian Airlines, crashed right after takeoff on its way to Addis Ababa, killing all 157 people on board, including the flight’s eight crew members.
Days later, President Donald J. Trump announced that American regulators would temporarily halt all flights by the Boeing 737 Max while investigators, and Boeing, sought to determine how a software system that was supposed to make the plane safer instead played a role in the catastrophes.
U.S. regulators were among the last to ground the model, but did so after pressure mounted and as 42 other countries took the drastic step to prevent further crashes.
Reporting by The New York Times and others eventually revealed competitive pressure, flawed design and problematic oversight had all played a role in the troubling history of the plane, Boeing’s best selling jet ever, and one with hundreds of billions of dollars in advance orders from airlines around the world when it was grounded.
What was the fallout?
Boeing agreed to pay $2.5 billion in a settlement with the Justice Department in 2021 to resolve a criminal charge that it had conspired to defraud the Federal Aviation Administration, which regulates the company and evaluates its planes.
In 2022, Boeing paid $200 million more in a deal with U.S. securities regulators over accusations that the company had misled investors by suggesting that human error was to blame for the two deadly crashes, and omitting the company’s concerns about the plane.
By the time the planes were recertified 20 months after the crashes in Indonesia and Ethiopia, Boeing estimated the crisis had cost the company $20.7 billion.
Which airlines use the 737 Max 9?
Part of Boeing’s single-aisle 737 Max series, the Max 9 can carry as many as 220 passengers, depending on its seating configuration. United Airlines has 79 Max 9s in service, the most of any airline, according to Cirium, an aviation analytics company. All told, there are 215 Max 9 aircraft in service around the world, Cirium said. United and Alaska Airlines have about a third of them.
Other companies flying the Max 9 include Copa Airlines of Panama and Aeromexico in the Americas, SCAT Airlines out of Kazakhstan, Iceland Air, Turkish Airlines, and FlyDubai.
A spokesperson for FlyDubai said that the three 737 Max 9 airliners in its fleet completed their necessary safety checks in the last 24 months and that the company was awaiting guidance from Boeing before carrying out any further inspections.
What happens next?
Major aviation safety incidents, including ones that do not produce injuries or loss of life, typically prompt immediate reviews by regulators in the United States, the European Union and China.
The investigators look at everything: the aircraft’s design; its manufacture, maintenance and inspection history; weather; air traffic control decisions; and actions by the flight crew. They look for causes of an incident as well as lessons for aviation safety.
In the case of the Alaska Airlines incident, the plane was manufactured in the United States and lost a fuselage section while flying in the United States. So the National Transportation Safety Board will be the lead agency responsible for investigating the incident.
Safety investigations can take many months. They involve technical experts from the government, from the airline that operated the aircraft, from labor unions and from the aircraft’s manufacturer — in this case, Boeing.
The F.A.A. does not need to wait for the safety board’s report before deciding whether to ground an aircraft model or order prompt inspections. Airlines typically rush to check their aircraft anyway as soon as they know what to look for.
What does the grounding mean for air travelers?
The grounding of one of the industry’s main workhorses could put a strain on travelers as airlines sometimes have to cancel flights because they lack the aircraft to replace the grounded model.
By Sunday afternoon, United had canceled 253 flights, or 9 percent of its schedule for the day, according to FlightAware, a flight tracking website, though some of those cancellations may also have been because of bad winter weather in the Northeast.
Alaska Airlines had canceled 163 flights, or 21 percent of its schedule by Sunday afternoon.
Alaska has issued a “systemwide flexible travel policy” allowing passengers to cancel or change their flights without incurring any fees. The airline is encouraging travelers to use the Alaska website or app themselves, rather than calling the airline’s customer service line.
United flight status updates can be found online. If a flight incurs significant delays, United will waive change fees or grant a travel credit or refund. The airline has not issued a specific waiver related to the aircraft inspections that would further relax policies.
And if a flight is delayed or canceled, the traveler may be entitled to compensation, depending on the circumstances.