Missing Bolts Found on Alaska Airlines Jet that Suffered Midair Decompression: NTSB Report
In a shocking revelation, the National Transportation Safety Board (NTSB) confirmed that four bolts were missing on an Alaska Airlines jet that experienced midair decompression during a flight last month. The missing bolts were responsible for securing a “door plug” on the fuselage of certain Boeing planes, specifically the 737 MAX 9 aircraft. The NTSB’s preliminary report stated that the bolts had been removed by Boeing during the plane’s final assembly process and had not been replaced.
The investigation into the accident revealed that the fuselage of the plane had been delivered to Boeing with defects, which required the removal of the door plug to address the issue. However, it seems that the bolts were not reinstalled after the repair. A metallurgic analysis of the recovered door plug confirmed that the bolts were indeed missing. Photos from Boeing following the repair also showed that the door plug had been replaced without the four bolts.
The consequences of the missing bolts were severe. As the plane departed from Portland International Airport in Oregon and climbed to about 16,000 feet, the pressurized cabin rapidly decompressed. This caused the flight deck door to open, resulting in pilots’ headsets being pulled off, passengers’ phones being ripped from their hands, and emergency oxygen masks falling from the ceiling. Fortunately, the window and middle seat next to the door plug were unoccupied at the time.
The incident has raised concerns about the safety of Boeing’s 737 MAX 9 and its manufacturing processes. The 737 MAX 9, along with the older generation 737-900, features a spot behind the wing for an extra emergency exit. However, airlines like United Airlines and Alaska Airlines, which have fewer seats on their aircraft, choose to install a lighter-weight “plug” instead. This plug gives the appearance of a seamless interior while still meeting safety requirements.
Following the accident, Alaska Airlines grounded its entire fleet of 737 MAX 9 aircraft. The Federal Aviation Administration (FAA) also ordered the grounding of all MAX 9 jets with a door plug, affecting 171 out of the 215 delivered aircraft of that type. Alaska Airlines has 65 MAX 9 planes in service, while United Airlines has 79.
Both airlines discovered loose bolts on numerous door plugs during inspections. However, as of Monday, about 94% of all 737 MAX 9 aircraft had been inspected and returned to service, according to the FAA. Thousands of flights had to be canceled during the grounding period.
This incident is yet another blow to Boeing, which has been facing a series of crises since 2020. The company has been working diligently to address quality control and manufacturing issues while attempting to regain the trust of airline customers and passengers. Boeing CEO Dave Calhoun acknowledged the company’s responsibility for the problem and expressed a commitment to earning back confidence through real action and transparency.
The FAA has also taken a firm stance, promising increased oversight of Boeing and temporarily blocking the company from increasing its production rate. The agency plans to conduct a comprehensive inspection of all 737 MAX jets to ensure safety and address any findings that may arise.
This incident serves as a reminder of the global grounding of the 737 MAX type in 2019 following two fatal crashes. Investigators determined that a flight control system called the Maneuvering Characteristics Augmentation System was responsible for the accidents. The system relied on a single sensor, and if that sensor became damaged, it could cause the plane to pitch down uncontrollably.
Boeing’s safety practices and records have come under scrutiny since then, with additional potential manufacturing defects being discovered in various plane types, including the MAX.
As Boeing works to rectify these issues and restore its reputation, it is clear that the aviation industry and regulators will maintain a vigilant eye on the company’s operations to ensure the safety of passengers and crew.