() The National Transportation Safety Board is meeting Tuesday to determine the probable cause of a midair cabin panel blowout of a Boeing 737 Max 9 flight in January 2024.

The board is reviewing findings from its 17-month investigation into the Alaska Airlines Flight 1282 incident, in which a door plug panel detached minutes after departure from Portland, Oregon. The failure created a powerful air vacuum that sucked objects from the cabin and scattered debris on the ground below, along with debris from the fuselage.

A preliminary report found that four bolts meant to secure the door plug were missing when the incident occurred and that Boeing records showed evidence that the plug had been reinstalled with no bolts prior to the initial delivery of the aircraft.

The NTSB is set to issue recommendations aimed at preventing similar failures in the future.

Factory workers interviewed during the investigation reported feeling pressured to meet production demands and said they were sometimes tasked with work they weren’t trained for, including handling the door plug on the plane involved.

Alaska Airlines door plug blowout

The incident occurred minutes after takeoff, as the plane flew at 16,000 feet. Oxygen masks dropped during the rapid decompression, and multiple cellphones and other objects were swept through the hole in the plane. Passengers were terrified by the wind and roaring noise.

Despite a loss of pressure in the cabin, none of the 171 passengers or six crew members died, and the plane landed safely back in Portland. Eight people on the aircraft reported minor injuries.

The door plug was found in the backyard of a high school science teacher in Cedar Hills, Oregon.

The plane involved had been delivered to Alaska Airlines in late October and had made about 150 flights. Shortly before the door panel blowout, the airline had stopped using the plane on flights to Hawaii after a warning light indicating a possible pressurization problem lit up on three different flights.

The incident led to several investigations into Boeing, most of which are still underway.

Boeing 737 Max issues

The Max version of Boeing’s bestselling 737 airplane has been the source of persistent issues for the company since two of the jets crashed, one in Indonesia in 2018 and another in Ethiopia in 2019, killing a combined 346 people.

Investigators determined those crashes were caused by a system that relied on a sensor providing faulty readings to push the nose down, leaving pilots unable to regain control. After the second crash, Max jets were grounded worldwide until the company redesigned the system.

Last month, the Justice Department reached a deal allowing Boeing to avoid criminal prosecution for allegedly misleading U.S. regulators about the Max before the two crashes.

However, Federal Aviation Administration regulators have capped Boeing’s 737 Max production at 38 jets per month while investigators ensure the company has strengthened its safety practices.

Tom Dempsey and the Associated Press contributed to this report.