Investigators found no work order for the activity or evidence that the door was reinstalled properly. NTSB officials said previously four bolts securing the panel went missing.
The NTSB said the “probable cause” was due to “Boeing Commercial Airplanes’ failure to provide adequate training, guidance and oversight necessary to ensure that manufacturing personnel could consistently and correctly comply with its parts removal process”. This was contained in a draft finding approved by board members at the meeting.
Boeing has revamped quality systems after the Alaska Airlines incident, redoubling training efforts and reducing work performed outside of sequence that can lead to production defects.
The company last year replaced its chief executive with former Rockwell Collins chief executive Kelly Ortberg, who has said improving Boeing’s corporate culture will take time.
Boeing said it was reviewing the report.
The NTSB directed recommendations at the US Federal Aviation Administration.
“Contributing to the accident was the Federal Aviation Administration’s ineffective compliance enforcement surveillance and audit planning activities, which failed to adequately identify and ensure that Boeing addressed the repetitive and systemic nonconformance issues associated with its parts removal process,” the investigation concluded.
– Agence France-Presse
