Alaska Airlines and passengers face more disruption from Boeing plane

For Alaska Airlines and its passengers, a return to normal may take some time.

The carrier has been placed under house arrest a fifth of his fleet after a fuselage panel on one of its Boeing 737 Max 9 jets blew out Friday evening, leaving a hole in the side of the plane.

The airline announced Wednesday that it would ground its Max 9 jets until at least Saturday, pending instructions from Boeing on how to conduct safety inspections.

United Airlines, with 79 aircraft, and Alaska, with 65, are the largest users of the Max 9 in the United States. But the jet model makes up less than 10 percent of United’s fleet, making it easier to fill gaps on planned routes than Alaska.

The grounding of the Max 9 has forced Alaska to cancel as many as 150 flights a day. About 20 percent of its flights were canceled on Wednesday, according to FlightAwarethat keeps track of flight data.

“It was extremely disruptive,” said Bret Peyton, director of operations at Alaska Airlines.

It is unclear when the planes will be back in the air.

The day after the incident, the Federal Aviation Administration ordered all 171 Max 9 jets in the United States to be grounded and inspected. Boeing gave airlines instructions on how to inspect the planes, but the aviation agency said Tuesday those instructions needed to be revised.

While it is unclear why Boeing’s initial inspection instructions fell short, the FAA said that “the safety of the flying public, and not speed,” would be prioritized when returning the planes to service.

“We’re just waiting for the FAA,” said Kathleen Bangs, aviation specialist at FlightAware. “You can rest assured that these airlines, especially Alaska, are in close contact with them.”

The National Transportation Safety Board is investigating the production and installation of the flyaway panel, known as a door plug. Alaska and United said they found loose parts during preliminary inspections of the panels.

When Alaska grounded the Max 9, it looked to see if other planes, even if different sizes, could fly the same routes. For example, if a flight is going somewhere with bad weather and is still at risk of being canceled, canceling the flight early can free up the plane.

“It’s a very complex set of considerations that we have to take into account,” Mr. Peyton said.

Ms Bangs said different jet models could be used interchangeably on land routes, so specific routes would not necessarily be disproportionately affected by groundings.

She noted that Alaska, whose main hub is Seattle-Tacoma International Airport, may also experience additional delays due to a winter storm in the Pacific Northwest.

Transportation Secretary Pete Buttigieg told reporters in Washington on Wednesday that the CEOs of Alaska and United had “reaffirmed their commitment to taking care of passengers” whose flights were canceled as part of the Max 9 grounding.

Mr. Buttigieg noted that, unlike a weather-related cancellation, this situation should be considered “manageable,” meaning customers are entitled to compensation.

January is usually a quiet time for airlines. If the outage had happened weeks earlier during the holidays, “it would have been a disaster,” said Helane Becker, an aviation analyst at TD Cowen.

“It’s unfortunate that it happened, but the fact that it happened now is better than if it had happened at a busier time,” Ms. Becker said.

Mark Walker And Niraj Chokshi reporting contributed.