Alaska Airlines 737-900 MAX loses a door in-flight out of PDX
Well, this is fun (not): https://leehamnews.com/2024/01/15/un...comment-509962
Just to be sure Boeing doesn't have trouble finding them later.
And as others mentioned, hope he has covered his tracks to prevent being traced.
Last edited by ST Dog; 23rd Jan 2024 at 06:38.
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Well, this is fun (not): https://leehamnews.com/2024/01/15/un...comment-509962
Edit: WRT MechEngr's remark about interested reporters, I note that one of the first comments in response to "throwawayboeing" is by Dominic Gates. We can be certain that he and the Seattle Times aviation team are all over this.
Dominic Gates
January 20, 2024
Wow!
@Throwaway: Please contact
Dominic Gates
Seattle Times
(206) 683-5329 cell
January 20, 2024
Wow!
@Throwaway: Please contact
Dominic Gates
Seattle Times
(206) 683-5329 cell
Last edited by OldnGrounded; 23rd Jan 2024 at 01:30. Reason: Add comment about reporters.
The background problem is, how do you perform what is akin to cancer surgery on this problem to save the patient, when there is evidence that this is not isolated, the whole MDD takeover has resulted in metastasis throughout the program. The cure for this may well be to cut the head off this patient, and replace it with a head from a group that are going to look at the long term health of the company and to try and turn around SS BCA, which has icebergs ahead, and has had a management in corporate level, and a board that has been busy on the poop deck, pooping away the future of the company. IMHO.
This is no better than the debacle on the Ducommon ring frame fiasco which is still a black mark on the company.
The company will blame the component manufacturer, deflection is easy, however, it wasn't the supplier of the part that didn't put the bolts in, and it is improbable that the mechanic on the line did this deliberately, and that strongly suggests that production pressure plays a part in this event. The process is flawed, if the steps are not tracked, then the QA group is not likely to detect such errors.
BCA will survive, and it should survive, not because it is too big to fail, (there are eminently sound alternatives) but the turn around of this company is not impossible, it is just impossible with the current pathological management that exists in Chicago.
At which point, it should.
I happen to like Boeings, and have enjoyed 20K + hours on their products, some are better than others, the company deserves better than their board and corporate bosses, and even the shareholders do, but they are also part of the problem. It is the program that takes a company that needs to be stable in the long term to take expedient short term decisions which risks the whole mess.
Issues with Spirit Quality Control are far from new. It's sad but inevitable that if the 'fix' to Spirit not doing their job right was for Renton to check and fix everything they did (or didn't do), it was rather inevitable that - eventually - something would slip through the cracks.
Belt and suspender solutions tend to fall flat when no one is putting on the belt...
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I've read throwawayboeing's post three times and sat quietly thinking about it for a while. If it's all true and accurate, and I ran the FAA, I think I'd suspend the relevant production certificates.
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Now, apparently other inspections have found other loose bolts, which may in fact suggest a more wide-reaching problem.
The NTSB report should be good reading, either way.
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On the other hand, if true, then the problem with this particular door was a one-off. A result of needing to open the door to replace the seal, and then not reinstalling the bolts properly. It doesn't suggest a design flaw or a step that was missed in production, but a "loophole" in the rework requirements that did not require QA signoff if the door was opened, but not removed, and only affecting this particular aircraft.
Now, apparently other inspections have found other loose bolts, which may in fact suggest a more wide-reaching problem.
The NTSB report should be good reading, either way.
Now, apparently other inspections have found other loose bolts, which may in fact suggest a more wide-reaching problem.
The NTSB report should be good reading, either way.
The other loose bolts are problematic in similar ways. They probably had some kind of capture feature or they'd have already fallen out, but they never should have come that loose in the first place. Of the ones I've seen pictures of, none were critical to keeping the plug in, but they still shouldn't be falling out.
The failure that is outlined in the article is troubling, but it is also not unexpected. What is frustrating is that the process is done in such a haphazard manner, when the information exists within the system that all is not well. The rectification of a defect such as this should have been a routine matter, save for the constraints of production & delivery schedules. After "392" discrepancies in the same small component, which are admittedly not identified as to severity of non conformance, but somewhere, a proper QA system that is not just lip service to having processes that are not followed, and inspectors that are disincentivised to discover issues is not a healthy place to be.
The background problem is, how do you perform what is akin to cancer surgery on this problem to save the patient, when there is evidence that this is not isolated, the whole MDD takeover has resulted in metastasis throughout the program. The cure for this may well be to cut the head off this patient, and replace it with a head from a group that are going to look at the long term health of the company and to try and turn around SS BCA, which has icebergs ahead, and has had a management in corporate level, and a board that has been busy on the poop deck, pooping away the future of the company. IMHO.
This is no better than the debacle on the Ducommon ring frame fiasco which is still a black mark on the company.
The company will blame the component manufacturer, deflection is easy, however, it wasn't the supplier of the part that didn't put the bolts in, and it is improbable that the mechanic on the line did this deliberately, and that strongly suggests that production pressure plays a part in this event. The process is flawed, if the steps are not tracked, then the QA group is not likely to detect such errors.
BCA will survive, and it should survive, not because it is too big to fail, (there are eminently sound alternatives) but the turn around of this company is not impossible, it is just impossible with the current pathological management that exists in Chicago.
The background problem is, how do you perform what is akin to cancer surgery on this problem to save the patient, when there is evidence that this is not isolated, the whole MDD takeover has resulted in metastasis throughout the program. The cure for this may well be to cut the head off this patient, and replace it with a head from a group that are going to look at the long term health of the company and to try and turn around SS BCA, which has icebergs ahead, and has had a management in corporate level, and a board that has been busy on the poop deck, pooping away the future of the company. IMHO.
This is no better than the debacle on the Ducommon ring frame fiasco which is still a black mark on the company.
The company will blame the component manufacturer, deflection is easy, however, it wasn't the supplier of the part that didn't put the bolts in, and it is improbable that the mechanic on the line did this deliberately, and that strongly suggests that production pressure plays a part in this event. The process is flawed, if the steps are not tracked, then the QA group is not likely to detect such errors.
BCA will survive, and it should survive, not because it is too big to fail, (there are eminently sound alternatives) but the turn around of this company is not impossible, it is just impossible with the current pathological management that exists in Chicago.
I (and many many other people) used to pull metrics from a ticketing system of record, and so did management. That was just how to do it. We also used email, assorted chat systems, and eventually Slack, but those are just to chat with people. Every action associated with an event, a deployment, a major change, or something otherwise ticketed was updated in the ticket. That record was preserved for posterity. 10-20+ year old tickets are still around. Our controls didn't have federal legal liability attached, at least not at the "a deliberate omission is illegal" level, but it was just a straightforward, methodical way to work, and with rare exceptions due to security, anyone could see work in a ticket.
Replacing a system of record, especially in a regulated, safety-conscious environment, is a massive undertaking and I expect that a goal of 10 years would be achievable, but wouldn't happen, because these things always run into execution problems due to management and technical turnover. Unless something radical and transformative is already underway at Boeing, it will take 10 years, 15 years, more, for the company to straighten up and fly right. This could have been started in the mid 90s, or any time since, but ... has it?
Boeing is of course too big to fail, and aviation exports rank very high (often #1) in US exports by category, but someone, somehow, needs to get this company back on track if it's going to continue to be a legitimate competitor to Airbus.
Frankly, I don't like my scenario. I did at first, but almost deleted it before you posted. I like the concept of one item replacing 4 safety bolts but it still leaves the splitting issue which I find alarming.
Frankly, I'm still in the dark about how that top edge passes the lip of the fuselage. I've read every post and watched Chris Brady's items. I know the system must work, but I can't 'see' the roller pins and guides doing everything that has to be done.
Frankly, I'm still in the dark about how that top edge passes the lip of the fuselage. I've read every post and watched Chris Brady's items. I know the system must work, but I can't 'see' the roller pins and guides doing everything that has to be done.
One possible explanation has been expressed here several times and, to the best of my knowledge, has not been refuted.
A single temporary locating pin, bolt, or mandrel, was inserted in one guide hole. The expectation was that this temporary pin would be replaced by a bolts after the other three bolts had been inserted but the task was interrupted. The trim panel was replaced with only the temporary pin/bolt/mandrel in place and it eventually fell out.
In my opinion no other satisfactory explanation has been suggested.
A single temporary locating pin, bolt, or mandrel, was inserted in one guide hole. The expectation was that this temporary pin would be replaced by a bolts after the other three bolts had been inserted but the task was interrupted. The trim panel was replaced with only the temporary pin/bolt/mandrel in place and it eventually fell out.
In my opinion no other satisfactory explanation has been suggested.
The most obvious way (in both senses of the word) to hold the door plug temporarily would be a suitable screwdriver inserted into one of the upper or lower bolt holes. Clearly that would be most easily fitted with the handle inboard (as opposed to the bolts, which when fitted have their heads outboard).
But I'm struggling to see how, in the absence of the bolts being fitted, a screwdriver sticking out of the door plug could fail to be noticed. It would also very likely obstruct the fitting of the trim panel.
Agree with all this post except, and I may be wrong, I think the door has to be pulled inwards for the roller pin to be at the back of the guide fitting ie. before the door is pulled down placing the pin at the top of the guide fitting (above where the stop bolt should be). Possibly. The way I see it the back of the guide fitting is on the outboard side of the door and as the pin is fixed, the door (and guide fitting) has to move inboard. Possibly.
What do you think ?
Also, as far as I can see from earlier pictures the stop pins are convex and the stop pads concave so we might need a tweak to cover the detail of how they engage / disengage
What do you think ?
Also, as far as I can see from earlier pictures the stop pins are convex and the stop pads concave so we might need a tweak to cover the detail of how they engage / disengage
Going back to my first post on this subject I'd said:
"The lift assist springs are resisting this downwards movement, and so the door needs to be held in place to allow the guide fitting locking bolts to be inserted under the guide pins, and the vertical movement arrestor bolts inserted through the hinge guide fittings"
In light of the latest news today (.https://leehamnews.com/2024/01/15/un...comment-509962) the implication is increasingly that the lock bolts were absent in the Alaska incident, rather than had failed in some way. So it seems that the lift assist springs are NOT necessarily strong enough to resist the final downwards movement of the door and its guide track fittings up to contact with the roller pins, otherwise the locking bolts would HAVE to be fitted to ensure the whole door wouldn't just pop up to the "ready to push open" position.
In fact, maybe Boeing should now increase the lift springs rate such that the door guide track fittings MUST be forcibly held down to insert the locking bolts!
The most obvious way (in both senses of the word) to hold the door plug temporarily would be a suitable screwdriver inserted into one of the upper or lower bolt holes. Clearly that would be most easily fitted with the handle inboard (as opposed to the bolts, which when fitted have their heads outboard).
D Bru's post #1208 shows an image of a door from an Alaska 737, I can't say the fit is what I would expect. Lighting may not be helping, but the gap at the rear looks tighter & the forward end seems to be depressed & nowhere near flush with the fuselage, I imagine that front edge may need to be depressed slighly to avoid airflow getting under the door, but by this much? (not suggesting that this is related to the cause of the blow out, more that there may be general issue with door fitment / build quality)
Last edited by Thrust Augmentation; 23rd Jan 2024 at 10:53.
On the other hand, if true, then the problem with this particular door was a one-off. A result of needing to open the door to replace the seal, and then not reinstalling the bolts properly. It doesn't suggest a design flaw or a step that was missed in production, but a "loophole" in the rework requirements that did not require QA signoff if the door was opened, but not removed, and only affecting this particular aircraft.
Now, apparently other inspections have found other loose bolts, which may in fact suggest a more wide-reaching problem.
The NTSB report should be good reading, either way.
Now, apparently other inspections have found other loose bolts, which may in fact suggest a more wide-reaching problem.
The NTSB report should be good reading, either way.
As I understand it, the work required to remove the door-plug would have required formal recording in the CMES system. The work required to 'merely' open the door-plug did not, even though, in both cases the retaining bolts needed to be removed. 'Merely' opening the door-plug to replace a seal was co-ordinated through the non-official-system-of-record used for co-ordinating work, called 'SAT'.
This means that any work that was accomplished by 'merely' opening the door-plug would not necessarily end up with an associated CMES record. The retaining bolts would still need to be removed, and replaced, but no record of this removal and expected replacement of the retaining bolts would have happened.
This means that any (remedial) work that required opening the door-plug, but not its complete removal, is open to the bolts being removed and accidentally not replaced. As far as the CMES system is concerned, the bolts never changed status, which would have been a physical impossibility: and another example of where records and reality do not match, you need to trust reality.
If my logic is wrong, I apologise, and would be grateful for clearer thinkers and those in possession of more and better information to correct me.
I don't know if this information was posted here already but here is a copy and paste from the article...
A reader at respected airline industry site Leeham News offered a comment that suggests they have access to Boeing’s internal quality control systems, and shares details of what they saw regarding the Boeing 737 MAX 9 flown by Alaska Airlines that had a door plug detach inflight, causing rapid decompression of the aircraft.
The takeaway appears to be that outsourced plane components have so many problems when they show up at the production line that Boeing’s quality control staff can’t keep up with them all.
Current Boeing employee here – I will save you waiting two years for the NTSB report to come out and give it to you for free: the reason the door blew off is stated in black and white in Boeings own records. It is also very, very stupid and speaks volumes about the quality culture at certain portions of the business.
…With that out of the way… why did the left hand (LH) mid-exit door plug blow off of the 737-9 registered as N704AL? Simple- as has been covered in a number of articles and videos across aviation channels, there are 4 bolts that prevent the mid-exit door plug from sliding up off of the door stop fittings that take the actual pressurization loads in flight, and these 4 bolts were not installed when Boeing delivered the airplane, our own records reflect this.
…As a result, this check job that should find minimal defects has in the past 365 calendar days recorded 392 nonconforming findings on 737 mid fuselage door installations (so both actual doors for the high density configs, and plugs like the one that blew out). That is a hideously high and very alarming number, and if our quality system on 737 was healthy, it would have stopped the line and driven the issue back to supplier after the first few instances.
…Now, on the incident aircraft this check job was completed on 31 August 2023, and did turn up discrepancies, but on the RH side door, not the LH that actually failed. I could blame the team for missing certain details, but given the enormous volume of defects they were already finding and fixing, it was inevitable something would slip through- and on the incident aircraft something did. I know what you are thinking at this point, but grab some popcorn because there is a plot twist coming up.
The next day on 1 September 2023 a different team (remember 737s flow through the factory quite quickly, 24 hours completely changes who is working on the plane) wrote up a finding for damaged and improperly installed rivets on the LH mid-exit door of the incident aircraft.
…Because there are so many problems with the Spirit build in the 737, Spirit has teams on site in Renton performing warranty work for all of their shoddy quality, and this SAT promptly gets shunted into their queue as a warranty item. Lots of bickering ensues in the SAT messages, and it takes a bit for Spirit to get to the work package. Once they have finished, they send it back to a Boeing QA for final acceptance, but then Malicious Stupid Happens! The Boeing QA writes another record in CMES (again, the correct venue) stating (with pictures) that Spirit has not actually reworked the discrepant rivets, they *just painted over the defects*. In Boeing production speak, this is a “process failure”. For an A&P mechanic at an airline, this would be called “federal crime”.
…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.
Boeing Whistleblower: Production Line Has “Enormous Volume Of Defects” Bolts On MAX 9 Weren’t Installed
by Gary Leff on January 22, 2024A reader at respected airline industry site Leeham News offered a comment that suggests they have access to Boeing’s internal quality control systems, and shares details of what they saw regarding the Boeing 737 MAX 9 flown by Alaska Airlines that had a door plug detach inflight, causing rapid decompression of the aircraft.
The takeaway appears to be that outsourced plane components have so many problems when they show up at the production line that Boeing’s quality control staff can’t keep up with them all.
Current Boeing employee here – I will save you waiting two years for the NTSB report to come out and give it to you for free: the reason the door blew off is stated in black and white in Boeings own records. It is also very, very stupid and speaks volumes about the quality culture at certain portions of the business.
…With that out of the way… why did the left hand (LH) mid-exit door plug blow off of the 737-9 registered as N704AL? Simple- as has been covered in a number of articles and videos across aviation channels, there are 4 bolts that prevent the mid-exit door plug from sliding up off of the door stop fittings that take the actual pressurization loads in flight, and these 4 bolts were not installed when Boeing delivered the airplane, our own records reflect this.
…As a result, this check job that should find minimal defects has in the past 365 calendar days recorded 392 nonconforming findings on 737 mid fuselage door installations (so both actual doors for the high density configs, and plugs like the one that blew out). That is a hideously high and very alarming number, and if our quality system on 737 was healthy, it would have stopped the line and driven the issue back to supplier after the first few instances.
…Now, on the incident aircraft this check job was completed on 31 August 2023, and did turn up discrepancies, but on the RH side door, not the LH that actually failed. I could blame the team for missing certain details, but given the enormous volume of defects they were already finding and fixing, it was inevitable something would slip through- and on the incident aircraft something did. I know what you are thinking at this point, but grab some popcorn because there is a plot twist coming up.
The next day on 1 September 2023 a different team (remember 737s flow through the factory quite quickly, 24 hours completely changes who is working on the plane) wrote up a finding for damaged and improperly installed rivets on the LH mid-exit door of the incident aircraft.
…Because there are so many problems with the Spirit build in the 737, Spirit has teams on site in Renton performing warranty work for all of their shoddy quality, and this SAT promptly gets shunted into their queue as a warranty item. Lots of bickering ensues in the SAT messages, and it takes a bit for Spirit to get to the work package. Once they have finished, they send it back to a Boeing QA for final acceptance, but then Malicious Stupid Happens! The Boeing QA writes another record in CMES (again, the correct venue) stating (with pictures) that Spirit has not actually reworked the discrepant rivets, they *just painted over the defects*. In Boeing production speak, this is a “process failure”. For an A&P mechanic at an airline, this would be called “federal crime”.
…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.
I don't know if this information was posted here already but here is a copy and paste from the article...
A reader at respected airline industry site Leeham News offered a comment that suggests they have access to Boeing’s internal quality control systems, and shares details of what they saw regarding the Boeing 737 MAX 9 flown by Alaska Airlines that had a door plug detach inflight, causing rapid decompression of the aircraft.
The takeaway appears to be that outsourced plane components have so many problems when they show up at the production line that Boeing’s quality control staff can’t keep up with them all.
Current Boeing employee here – I will save you waiting two years for the NTSB report to come out and give it to you for free: the reason the door blew off is stated in black and white in Boeings own records. It is also very, very stupid and speaks volumes about the quality culture at certain portions of the business.
…With that out of the way… why did the left hand (LH) mid-exit door plug blow off of the 737-9 registered as N704AL? Simple- as has been covered in a number of articles and videos across aviation channels, there are 4 bolts that prevent the mid-exit door plug from sliding up off of the door stop fittings that take the actual pressurization loads in flight, and these 4 bolts were not installed when Boeing delivered the airplane, our own records reflect this.
…As a result, this check job that should find minimal defects has in the past 365 calendar days recorded 392 nonconforming findings on 737 mid fuselage door installations (so both actual doors for the high density configs, and plugs like the one that blew out). That is a hideously high and very alarming number, and if our quality system on 737 was healthy, it would have stopped the line and driven the issue back to supplier after the first few instances.
…Now, on the incident aircraft this check job was completed on 31 August 2023, and did turn up discrepancies, but on the RH side door, not the LH that actually failed. I could blame the team for missing certain details, but given the enormous volume of defects they were already finding and fixing, it was inevitable something would slip through- and on the incident aircraft something did. I know what you are thinking at this point, but grab some popcorn because there is a plot twist coming up.
The next day on 1 September 2023 a different team (remember 737s flow through the factory quite quickly, 24 hours completely changes who is working on the plane) wrote up a finding for damaged and improperly installed rivets on the LH mid-exit door of the incident aircraft.
…Because there are so many problems with the Spirit build in the 737, Spirit has teams on site in Renton performing warranty work for all of their shoddy quality, and this SAT promptly gets shunted into their queue as a warranty item. Lots of bickering ensues in the SAT messages, and it takes a bit for Spirit to get to the work package. Once they have finished, they send it back to a Boeing QA for final acceptance, but then Malicious Stupid Happens! The Boeing QA writes another record in CMES (again, the correct venue) stating (with pictures) that Spirit has not actually reworked the discrepant rivets, they *just painted over the defects*. In Boeing production speak, this is a “process failure”. For an A&P mechanic at an airline, this would be called “federal crime”.
…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.
Boeing Whistleblower: Production Line Has “Enormous Volume Of Defects” Bolts On MAX 9 Weren’t Installed
by Gary Leff on January 22, 2024A reader at respected airline industry site Leeham News offered a comment that suggests they have access to Boeing’s internal quality control systems, and shares details of what they saw regarding the Boeing 737 MAX 9 flown by Alaska Airlines that had a door plug detach inflight, causing rapid decompression of the aircraft.
The takeaway appears to be that outsourced plane components have so many problems when they show up at the production line that Boeing’s quality control staff can’t keep up with them all.
Current Boeing employee here – I will save you waiting two years for the NTSB report to come out and give it to you for free: the reason the door blew off is stated in black and white in Boeings own records. It is also very, very stupid and speaks volumes about the quality culture at certain portions of the business.
…With that out of the way… why did the left hand (LH) mid-exit door plug blow off of the 737-9 registered as N704AL? Simple- as has been covered in a number of articles and videos across aviation channels, there are 4 bolts that prevent the mid-exit door plug from sliding up off of the door stop fittings that take the actual pressurization loads in flight, and these 4 bolts were not installed when Boeing delivered the airplane, our own records reflect this.
…As a result, this check job that should find minimal defects has in the past 365 calendar days recorded 392 nonconforming findings on 737 mid fuselage door installations (so both actual doors for the high density configs, and plugs like the one that blew out). That is a hideously high and very alarming number, and if our quality system on 737 was healthy, it would have stopped the line and driven the issue back to supplier after the first few instances.
…Now, on the incident aircraft this check job was completed on 31 August 2023, and did turn up discrepancies, but on the RH side door, not the LH that actually failed. I could blame the team for missing certain details, but given the enormous volume of defects they were already finding and fixing, it was inevitable something would slip through- and on the incident aircraft something did. I know what you are thinking at this point, but grab some popcorn because there is a plot twist coming up.
The next day on 1 September 2023 a different team (remember 737s flow through the factory quite quickly, 24 hours completely changes who is working on the plane) wrote up a finding for damaged and improperly installed rivets on the LH mid-exit door of the incident aircraft.
…Because there are so many problems with the Spirit build in the 737, Spirit has teams on site in Renton performing warranty work for all of their shoddy quality, and this SAT promptly gets shunted into their queue as a warranty item. Lots of bickering ensues in the SAT messages, and it takes a bit for Spirit to get to the work package. Once they have finished, they send it back to a Boeing QA for final acceptance, but then Malicious Stupid Happens! The Boeing QA writes another record in CMES (again, the correct venue) stating (with pictures) that Spirit has not actually reworked the discrepant rivets, they *just painted over the defects*. In Boeing production speak, this is a “process failure”. For an A&P mechanic at an airline, this would be called “federal crime”.
…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.