Boeing 737 Max 9 plane that lost door plug was missing bolts

The Boeing 737 Max 9 airplane that made an emergency landing last month after its door plug blew out in midair was missing four bolts that would have prevented the panel from moving upward, according to a preliminary report from the National Transportation Safety Board.

As part of the NTSB’s investigation, the agency found that the “absence of contact damage or deformation” around holes associated with vertical movement bolts indicate that four bolts “that prevent upward movement” of the door panel were missing before the panel moved upward off the stop pads, according to the report.

Boeing said in a statement that the company would review the NTSB’s findings “expeditiously” and will continue to “fully and transparently” cooperate with this investigation as well as a separate investigation by the Federal Aviation Administration.

“Whatever final conclusions are reached, Boeing is accountable for what happened,” company Chief Executive Dave Calhoun said in the statement. “An event like this must not happen on an airplane that leaves our factory. We simply must do better for our customers and their passengers.”

Boeing said it has implemented a quality control plan to ensure all 737 Max 9 mid-exit door plugs are installed “according to specifications,” including new inspections of door plug assembly at both suppliers’ factories as well as in-house, and adding “signage and protocol” to fully document when the door plug is opened or removed in the Boeing factory.

The NTSB said its investigation into Alaska Airlines Flight 1282, which was traveling from Portland International Airport to Ontario, is ongoing.

The Boeing 737 Max 9 airplane that made an emergency landing last month after its door plug blew out in midair was missing four bolts that would have prevented the panel from moving upward, according to a preliminary report from the National Transportation Safety Board.

As part of the NTSB’s investigation, the agency found that the “absence of contact damage or deformation” around holes associated with vertical movement bolts indicate that four bolts “that prevent upward movement” of the door panel were missing before the panel moved upward off the stop pads, according to the report.

Boeing said in a statement that the company would review the NTSB’s findings “expeditiously” and will continue to “fully and transparently” cooperate with this investigation as well as a separate investigation by the Federal Aviation Administration.

“Whatever final conclusions are reached, Boeing is accountable for what happened,” company Chief Executive Dave Calhoun said in the statement. “An event like this must not happen on an airplane that leaves our factory. We simply must do better for our customers and their passengers.”

Overall view of the MED plug and associated components removed from the accident airplane as received at the NTSB Materials Laboratory.

(NTSB)

Boeing said it has implemented a quality control plan to ensure all 737 Max 9 mid-exit door plugs are installed “according to specifications,” including new inspections of door plug assembly at both suppliers’ factories as well as in-house, and adding “signage and protocol” to fully document when the door plug is opened or removed in the Boeing factory.

The NTSB said its investigation into Alaska Airlines Flight 1282, which was traveling from Portland International Airport to Ontario, is ongoing.