From the blog mentioned above:
“Unplanned” removal, installation inspection procedure at Boeing
https://leehamnews.com/2024/01/15/unpla ... ent-509962
Jan. 15, 2024, © Leeham News:
It’s not supposed to happen.
The door plug on the Boeing 737-9 MAX isn’t supposed to separate from the airplane in flight, as it did on Alaska Airlines Flight 1282 on Jan. 5 this year.
There is conflicting reporting whether the emergency exit or door plug is opened on the Boeing 737 final assembly line for access to the interior. Examining Google images, two photos show the exit or plug closed while over-wing exits are open. Credit: Unknown.
The investigation by the National Transportation Safety Board (NTSB) is in its infancy. Early evidence suggests four bolts intended to prevent the door plug from shifting in its attachment brackets either failed or weren’t installed. Inspections after the 1282 incident by Alaska, and United Airlines found loose bolts in other MAX 9s. The Federal Aviation Administration (FAA) on Jan. 6 grounded the 171 MAX 9s operated by the two carriers until inspections and repairs, if needed, are completed.
Boeing CEO David Calhoun, while telling CNBC that he wasn’t pointing fingers, did precisely that. He said Spirit AeroSystems had a “quality escape,” adding that Boeing failed to catch it, so it also had a quality escape.
How could this happen? The NTSB probe will presumably figure this out. Spirit ships the 737-9 fuselages with the door plug installed. Conflicting reporting suggests that Spirit is supposed to install the door plugs in the final, secure condition; or these are shipped with the plugs in place but in a condition that Boeing would later secure. The NTSB will sort this out, too.
Regardless, Boeing should have inspected the door plugs and assured these are in final condition prior to delivery. The Seattle Times reported on Jan. 14 that contrary to other reports, Boeing doesn’t open or remove the door plug when the MAX 9 is in final assembly. A retired Boeing safety employee with assembly line experience says Spirit ships the door plugs in a temporary condition, expecting that Boeing may remove them during final assembly.
Special inspection procedure of the door plug
LNA outlined Boeing’s inspection procedures in a Jan. 8 post. In the event, for whatever reason, Boeing does open or remove the door plug, there is a special procedure that should be followed to ensure the plug is properly reinstalled.
Here is that procedure.
The quality escapes referred to by Calhoun are inspection procedures. Failing to catch something in an inspection is also called an inspection escape.
What is outlined below is a theory, and not proven fact with the MAX 9 involved, or others in which discrepancies have been found. This procedure is related detailing Boeing’s procedure, just as LNA’s Jan. 8 post outlined procedures.
If Boeing, for any reason, removed the door plug on Alaska’s MAX 9, failure to reinstall the plug properly may not be an inspection escape. An inspection escape means that a planned installation/re-installation operation was inspected, and the mechanic and inspector got it wrong. While not impossible, this is a tough theory to accept, given the four-step inspection process outlined in the Jan. 8 post.
On the other hand, unplanned removal and installation calls for another procedure.
Boeing goes to great lengths to document unplanned removals by logging all the disassembly steps on the ship’s record paper. Quality Assurance inspects the reassembly process of the unplanned removal event. This door plug’s poor installation could, in theory, be the result of a production shortcut where the shop needed the door out of the way. The door could have been reinstalled incorrectly. The retired Boeing safety employee says the door plugs are often removed.
Unplanned removals happen “a lot,” the retired Boeing employee told LNA. “There are a multitude of reasons,” he said.
Cost-cutting on inspectors; new workforce
If the unplanned removal proves to hold water, and as noted, this is only hypothesis, then how could the inspection process break down? And how could experienced assembly line workers miss either escapes from Spirit or reinstalling the door plug properly?
The roots may go back years.
Under the regime of former CEO Dennis Muilenburg, quality inspectors were laid off and their duties assigned to others. Boeing’s touch-labor union, the IAM 751, protested that this was unsafe. The protests largely fell on deaf ears.
“I don’t call them quality escapes anymore. I call them safety escapes because Boeing doesn’t have a quality organization anymore,” the retired Boeing safety employee said. A procedure called “Quality Buyback” has been reduced over the years, he said.
In its May 2019 Aero Mechanic employee newsletter, the IAM 751 wrote that it continued to object to Boeing’s plan to eliminate quality assurance inspectors. The union vowed to have its members “reveal instances where Boeing is not following its own internal process.”
“Removing inspections and discovering defects further down line will cause an abundance of out-of-sequence work, [and] more damage to the airplane through rework….”
“We have engaged…in what we see as a long battle to protect the integrity of our manufacturing process,” the union wrote in its newsletter.
When the MAX was grounded in May 2019 for what would be 21 months, Boeing laid off many of its final assembly line workers. When the COVID-19 pandemic began in May 2020, Boeing laid off or offered early retirement to thousands or workers company wide, including more from the 737 FAL.
When production resumes in May 2021, ahead of the recertification the following November, Boeing had to hire new employees without FAL experience. A learning curve is necessary for efficient production.
Returning the MAX 9 to service
The FAA grounded the US MAX 9s on Jan. 6. Some other airlines followed the FAA’s lead. Initially, it was thought that inspecting the door plugs and making any fixes would be a quick process. But more than a week later, the FAA was still requiring details from Boeing and that 40 inspections and repairs (if required) would have to be completed before return to service was approved.
Why is the FAA being so slow? There are a couple of theories.
The first is that the incident involves Boeing and the MAX. The FAA was burned by the certification process of the MAX in the beginning, which was revealed during the 2019 grounding and accident investigations of Lion Air and Ethiopian Airlines. One theory suggests that the FAA isn’t going to get burned again.
It’s common knowledge within the airline community that the relationship between Boeing and the FAA has never recovered from the original MAX crisis. The FAA removed authority from Boeing to certify new MAXes as airworthy. The FAA must sign off on each delivery. This hand slapping was later extended to the 787 when production and quality problems were discovered at the Charleston final assembly line.
Certifying the MAX 7 and 10
Recertifying the MAX after the crash-related groundings proved to be an arduous process. So is certification of the MAX 7, which otherwise is ready to go, and the MAX 10, for which flight testing is in its early stages. But certification of the MAX 7 has taken far longer than anyone expected.
The FAA asks questions and Boeing responds. This generates more questions and more responses. And the cycle repeats, over and over again. Shortly before the Alaska incident, Boeing asked for an exemption for the MAX 7 from a safety regulation. Doubts already existed whether the FAA would grant the exemption. Now, doing so seems unlikely.
Another theory why the FAA is moving slowly on the MAX 9 is, perhaps unsurprisingly, politics. Some members of Congress were quick to demand hearings about the FAA oversight of Boeing, again. The FAA has, once more, come under criticism for its handling of the entire MAX history.
The FAA launched a formal investigation into the MAX 9 incident, in parallel to that of the NTSB.
The FAA is also expected to receive this month a draft of a safety audit authorized during the original MAX crisis. Members of the special committee included experts from across aviation. LNA has learned that the draft conclusions won’t be favorable to Boeing. There is no public release date of this report that’s been announced.
PP