Boeing Says It’s Changing Type of Panel That Blew Off Alaska Airlines Jet

Boeing officials told regulators on Tuesday that the aircraft maker would make changes to how it designed and produced the type of panel that blew off an Alaska Airlines jet shortly after takeoff in January.

Boeing told regulators that it was redesigning its door plugs — the panels that replace emergency-exit doors in certain design configurations that create more seats — so that its warning systems could detect any malfunctions.

The design changes are expected to be “implemented within the year,” said Elizabeth Lund, a senior vice president for quality at Boeing, who testified on Tuesday at an investigative hearing held by the National Transportation Safety Board, an independent government investigative agency.

The hearing on Tuesday revealed that Boeing employees removed a door plug from what would later be the Alaska Airlines jet to repair damaged rivets, but without any required internal authorization or paperwork detailing the removal of the panel — a critical structural element. The safety board’s investigation found earlier this year that the plane, a 737 Max 9, left the Boeing factory in Renton, Wash., missing bolts that should have held in place the door plug that blew off midair.

The safety board’s chairwoman, Jennifer Homendy, suggested at the hearing that the work culture at Boeing prioritized meeting production schedules over safety standards, and led to an overtaxed work force and lapses in the production process.

On Tuesday, Ms. Homendy read quotes from the board’s interviews with mechanics who have worked at the Boeing facility for years. The workers testified to board investigators that they were regularly pressured into working 10 to 12 hours a day, six to seven days a week, Ms. Homendy said.