The National Transportation Safety Board (NTSB) has released its findings on last year’s dramatic in-flight incident involving an Alaska Airlines Boeing 737 MAX 9, pinpointing Boeing’s internal failures as the primary cause.

According to the NTSB report issued Tuesday, the blowout of the mid-exit door (MED) plug was the result of Boeing’s failure to “provide adequate training, guidance and oversight” to its factory workers. The report further criticized the Federal Aviation Administration (FAA) for ineffective oversight, stating that the agency failed to ensure Boeing addressed what the NTSB described as “repetitive and systemic” issues related to the handling and installation of aircraft components.

The NTSB also highlighted shortcomings in Boeing’s voluntary Safety Management System (SMS). In the two years leading up to the accident, investigators found the SMS to be inadequate, poorly integrated with Boeing’s quality management system, and lacking formal FAA supervision. The report stressed the need for accurate, continuous safety data and a strong safety culture to properly manage risks and prevent such failures.

The incident occurred on January 5, 2024, when Alaska Airlines Flight 1282 was climbing through 14,830 feet after departing Portland, Oregon, en route to Ontario, California. Just six minutes into the flight, the left MED plug detached from the aircraft, causing a sudden depressurization. The force of the decompression pulled personal belongings out of the aircraft, deployed oxygen masks, and even swung open the flight deck door, injuring a flight attendant. Seven passengers sustained minor injuries, while the two pilots, three other flight attendants, and 164 remaining passengers escaped unharmed.

This high-profile incident has placed renewed scrutiny on Boeing’s manufacturing processes and the FAA’s regulatory oversight, as both organizations continue to face growing public and industry concern over aircraft safety.