Boeing to Make Design Changes to Prevent Future 737-9 Door Panel Blowouts
Boeing announced on August 6 that it plans to implement design changes to prevent future mid-air cabin panel blowouts, similar to the incident that occurred on an Alaska Airlines 737-9 flight in January 2024. This incident has plunged Boeing into its second major crisis in recent years.
Investigation and Findings
The National Transportation Safety Board (NTSB) and Boeing have yet to determine who removed and reinstalled the plane’s door plug during production. The NTSB concluded the first of two days of hearings, lasting nearly 10 hours, into the mid-air emergency that severely damaged Boeing’s reputation. This incident led to the MAX 9’s grounding for two weeks, a production expansion ban by the Federal Aviation Administration (FAA), a criminal investigation, and the departure of several key executives.
Investigators found that the door plug in the Alaska MAX 9 was missing four key bolts. Boeing has faced extensive questions regarding the production of the accident aircraft and the lack of documentation detailing the removal of the door plug.
Boeing’s Response and Future Actions
NTSB Chair Jennifer Homendy criticized Boeing’s safety culture, urging the company to make significant improvements. “The safety culture needs a lot of work,” Homendy stated.
Boeing’s Senior Vice President for Quality, Elizabeth Lund, indicated that the company is working on design changes expected to be implemented within the year and retrofitted across the fleet. “They are working on some design changes that will allow the door plug to not be closed if there’s any issue until it’s firmly secured,” Lund said.
Two Boeing employees likely involved in the door plug’s removal have been placed on paid administrative leave. The NTSB also released 3,800 pages of factual reports and interviews from the ongoing investigation.
Boeing has acknowledged that no paperwork exists to document the removal of the four missing bolts. To prevent future incidents, Boeing has introduced a bright blue and yellow sign on the door plug when it arrives at the factory, stating in large letters: “Do not open,” with added redundancies to ensure the plug is not inadvertently opened.
Witness Accounts and Additional Measures
A flight attendant described the moment of terror when the door plug blew out, saying, “There was a really loud bang and lots of whooshing air, like the door burst open. Masks came down, and I saw the galley curtain get sucked towards the cabin.”
Doug Ackerman, Vice President of Supplier Quality for Boeing, noted that Boeing has 1,200 active suppliers for its commercial airplanes and 200 supplier quality auditors. Lund mentioned that Boeing is currently building “in the 20s” for monthly MAX production, far fewer than the 38 per month it is allowed to produce.
Recent Developments and Legal Issues
Last month, Boeing agreed to buy back Spirit AeroSystems, whose core plants it spun off in 2005, for $4.7 billion in stock. The NTSB hearings are reviewing key issues, including 737 manufacturing and inspections, safety management, and quality management systems, FAA oversight, and issues surrounding the door plug.
Jonathan Arnold, an Aviation Safety Inspector at the FAA, highlighted systemic issues at Boeing’s factory, including employees not following instructions. “That seems to be systemic where they deviate from their instructions,” Arnold said.
Before the January 5 accident, every 737 fuselage delivered to Boeing by Spirit AeroSystems had defects. “What we don’t want is the really big defects that are impactful to the production system,” Lund said. Homendy expressed frustration with Boeing, stating, “There’s not a lot of trust, there’s a lot of distrust within the workforce.”
Boeing executive Carole Murray detailed various problems with fuselages from Spirit AeroSystems, including sealant issues and multiple defects around the window frame and skin.
Michelle Delgado, a structures mechanic who worked on the Alaska MAX 9 aircraft, told the NTSB that the heavy workload often required long hours to complete tasks.
Additionally, the NTSB noted that Boeing violated investigation rules when Lund provided non-public information to the media and speculated about possible causes.
Last month, Boeing agreed to plead guilty to a criminal fraud conspiracy charge and pay a fine of at least $243.6 million to resolve a Justice Department investigation into two fatal 737 MAX crashes.
Sources: AirGuide Business airguide.info, bing.com, reuters.com