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It's an anonymous comment posted here: https://leehamnews.com/2024/01/15/unplanned-removal-installation-inspection-procedure-at-boeing/#comment-509962 https://l

by mjcl 3y ago

It's an anonymous comment posted here: https://leehamnews.com/2024/01/15/unplanned-removal-installation-inspection-procedure-at-boeing/#comment-509962 https://leehamnews.com/2024/01/15/unplanned-removal-installa... . It was posted before any official information was released and seems to track with information that was subsequently released.

bigiain 3y ago
Thanks - that's exactly what I was remembering. (Terminology as described further upthread at that link: CMES is an official record system for the plane. SAT is described as "Like Slack" and not an official record of the plane and its maintenance) "finally we get to the damning entry which reads something along the lines of “coordinating with the doors team to determine if the door will have to be removed entirely, or just opened. If it is removed then a Removal will have to be written.” Note: a Removal is a type of record in CMES that requires formal sign off from QA that the airplane been restored to drawing requirements. If you have been paying attention to this situation closely, you may be able to spot the critical error: regardless of whether the door is simply opened or removed entirely, the 4 retaining bolts that keep it from sliding off of the door stops have to be pulled out. A removal should be written in either case for QA to verify install, but as it turns out, someone (exactly who will be a fun question for investigators) decides that the door only needs to be opened, and no formal Removal is generated in CMES (the reason for which is unclear, and a major process failure). Therefore, in the official build records of the airplane, a pressure seal that cannot be accessed without opening the door (and thereby removing retaining bolts) is documented as being replaced, but the door is never officially opened and thus no QA inspection is required. This entire sequence is documented in the SAT, and the nonconformance records in CMES address the damaged rivets and pressure seal, but at no point is the verification job reopened, or is any record of removed retention bolts created, despite it this being a physical impossibility."
- jhugo 3y ago
  I wonder if the system recording the actions could have knowledge of these types of dependencies between actions, so it could refuse to record a log which is physically impossible (replaced a seal that — due to a plug not being opened — you cannot physically access).
- hgomersall 3y ago
  It's not clear to me - was the seal replacement documented in CMES? Is there not some dependency tree such that a cascade of sign-offs are required when one thing is changed? Clearly, changing the seal has dependencies which should automatically be flagged.

by mjcl 3y ago

bigiain 3y ago

Thanks - that's exactly what I was remembering. (Terminology as described further upthread at that link: CMES is an official record system for the plane. SAT is described as "Like Slack" and not an official record of the plane and its maintenance) "finally we get to the damning entry which reads something along the lines of “coordinating with the doors team to determine if the door will have to be removed entirely, or just opened. If it is removed then a Removal will have to be written.” Note: a Removal is a type of record in CMES that requires formal sign off from QA that the airplane been restored to drawing requirements. If you have been paying attention to this situation closely, you may be able to spot the critical error: regardless of whether the door is simply opened or removed entirely, the 4 retaining bolts that keep it from sliding off of the door stops have to be pulled out. A removal should be written in either case for QA to verify install, but as it turns out, someone (exactly who will be a fun question for investigators) decides that the door only needs to be opened, and no formal Removal is generated in CMES (the reason for which is unclear, and a major process failure). Therefore, in the official build records of the airplane, a pressure seal that cannot be accessed without opening the door (and thereby removing retaining bolts) is documented as being replaced, but the door is never officially opened and thus no QA inspection is required. This entire sequence is documented in the SAT, and the nonconformance records in CMES address the damaged rivets and pressure seal, but at no point is the verification job reopened, or is any record of removed retention bolts created, despite it this being a physical impossibility."

jhugo 3y ago
I wonder if the system recording the actions could have knowledge of these types of dependencies between actions, so it could refuse to record a log which is physically impossible (replaced a seal that — due to a plug not being opened — you cannot physically access).
hgomersall 3y ago
It's not clear to me - was the seal replacement documented in CMES? Is there not some dependency tree such that a cascade of sign-offs are required when one thing is changed? Clearly, changing the seal has dependencies which should automatically be flagged.