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Alaska Airlines 737-900 MAX loses a door in-flight out of PDX

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Alaska Airlines 737-900 MAX loses a door in-flight out of PDX

Old 23rd Jan 2024, 23:45
  #1281 (permalink)  
 
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Originally Posted by MechEngr
The Spirit warranty team was there to fix problems reported by Boeing, not to add to the list of discovered problems. No paperwork, no problems.
But the Spirit team didn't make the CMES entries related to the work on the seal and associated "opening" or "removal" of the plug, or determine how it would be characterized. They couldn't, because they don't have access.
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Old 23rd Jan 2024, 23:49
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Alaska Airlines CEO: We found 'many' loose bolts on our Max 9 planes following near-disaster

"I'm angry," Ben Minicucci said. "This happened to Alaska Airlines. It happened to our guests and happened to our people."
https://www.nbcnews.com/business/bus...ays-rcna135316

Note that as an investigation stakeholder he is legally constrained to be factual, not speculative.

Still waiting for the good news part.

Last edited by remi; 24th Jan 2024 at 00:06.
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Old 23rd Jan 2024, 23:53
  #1283 (permalink)  
 
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Originally Posted by OldnGrounded
But the Spirit team didn't make the CMES entries related to the work on the seal and associated "opening" or "removal" of the plug, or determine how it would be characterized. They couldn't, because they don't have access.
Yeah this is a world class failure because among other things it's on its face inevitable. Or designed to fail.

Bear in mind that like many or most people here I love what Boeing used to do and the superb aircraft they made. It just seems like since 1997 that's not what they do or make any longer, and it makes me sad and upset.

A standby captain I used to golf with flew 757 domestic. He related that one day he was deadheading/relocating west from somewhere in Texas. Got ATC to clear him direct to something like 40k and flew straight up there like an F-4 on military power. Ah the good old days when the future of Boeing single aisle might have had main landing gear doors.

Last edited by remi; 24th Jan 2024 at 00:11.
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Old 24th Jan 2024, 00:09
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Terminology: Door Vs Plug is more than a pedantic debate - looks like a major cause

Throughout this thread there have been numerous terminology debates about Door Vs Plug that many people just rolled their eyes to and ignored as being pedantic.

Turns out it may be the one of the largest holes in the Swiss cheese if the recent anonymous account is correct.

Removing a plug requires an entry in the formal tracking and inspection system, with a full audit trail and validation of all processes undertaken.

Opening a door to perform an inspection or for maintenance doesn't. In this case it was classifed as a door being opened, even though it was bolted in. As such, there was no audit trail of the bolts, whose status remained unchanged in the system, which was a physical impossibility.

Last edited by eppy; 24th Jan 2024 at 13:53.
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Old 24th Jan 2024, 00:16
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Originally Posted by eppy
Throughout this thread there have been numerous terminology debates about Door Vs Plug that many people just rolled their eyes to and ignored as being pedantic.

Turns out it may be the one of the largest holes in the Swiss cheese if the recent anonymous account is correct.

Removing a plug requires an entry in the formal tracking and inspection system, with a full audit trail and validation of all processes undertaken.

Opening a door to perform an inspection or for maintenance doesn't. In this case it was classifed as a door being opened, even though it was bolted in. As such, there was no audit trail of the bolts, whose status remained unchanged in the system, which was a physical impossibility.
One wonders if a tiny contribution to doing the right thing might be different terminology, e.g. "PORT COVER."

As someone at various times working on UIs, manuals, articles, and whatnot, I obsess over terminology.

It's not unreasonable to obsess. After all, a lot of thought went into the NATO/aviation phonetic alphabet, for the exact same reasons that it's important to communicate understandably and precisely to software users.
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Old 24th Jan 2024, 00:17
  #1286 (permalink)  
 
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Originally Posted by remi
The important question is why would someone be motivated to avoid the paperwork? Presumably if you are in aviation you have a very high tolerance for, and even like for, paperwork.

So have they hired people who hate paperwork? People who are illiterate? Or have they got management that can't stand waiting for paperwork?
Do you honestly know anybody who likes doing paperwork? Because in my 40-year career I never met one. Did the paperwork? Yes. Tolerated paperwork? Yes. Liked doing paperwork? NO!!!
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Old 24th Jan 2024, 00:24
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Originally Posted by tdracer
Do you honestly know anybody who likes doing paperwork? Because in my 40-year career I never met one. Did the paperwork? Yes. Tolerated paperwork? Yes. Liked doing paperwork? NO!!!
I have seen many people, and known a few, who find paperwork relaxing and/or gratifying. I don't, but I can accept that many people do.
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Old 24th Jan 2024, 01:35
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Air Alaska CEO states their own checks of 737 Max planes find many loose bolts.
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Old 24th Jan 2024, 01:57
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Originally Posted by OldnGrounded
But the Spirit team didn't make the CMES entries related to the work on the seal and associated "opening" or "removal" of the plug, or determine how it would be characterized. They couldn't, because they don't have access.
This is true. What is also true is Spirit should have their own system for tracking work that should parallel CMES. Still, they did not formally alert Boeing that additional work needed to be entered into CMES to reflect the additional defect.
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Old 24th Jan 2024, 02:16
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Originally Posted by MechEngr
This is true. What is also true is Spirit should have their own system for tracking work that should parallel CMES. Still, they did not formally alert Boeing that additional work needed to be entered into CMES to reflect the additional defect.
How would anyone know that they formally alerted Boeing or anyone else? Is there any system of record more sophisticated than email or typed letters that documents that? Is there any mechanism that makes such communication "official" rather than "discussion"?

There are countless memos from management and engineers found in boxes of discovery material that have led to awards to plaintiffs, but pretty close to zero such memos result in regulatory action beforehand.
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Old 24th Jan 2024, 02:42
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Originally Posted by RickNRoll
Air Alaska CEO states their own checks of 737 Max planes find many loose bolts.
Exclusive: Boeing presses suppliers on tightening bolts after loose parts found in 737 MAX 9 checks

"[. . .]
Alaska Airlines CEO Ben Minicucci said in an NBC News interview that aired Tuesday that the airline found 'some loose bolts on many' MAX 9s during inspections.

'My demand on Boeing is, what are they going to do to improve their quality programs in house?' Minicucci said."
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Old 24th Jan 2024, 02:46
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Originally Posted by remi
How does it happen that America's premier (and, formerly, the world's premier) commercial airframe manufacturer sets itself on a path into the wilderness, and 27 years later, no one is looking for the way back? Is it really as simple as a room full of financial elite are sucking out all the money they can from the former US #1 export industry, and aside from that they don't care?
If you had to pick one thing, that would have to be it.
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Old 24th Jan 2024, 03:04
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Originally Posted by MechEngr
Still, they [Spirit] did not formally alert Boeing that additional work needed to be entered into CMES to reflect the additional defect.
I don't understand which "additional defect" you mean. Spirit did, according to throwawayboeing, inform Boeing about the damaged seal. I don't think it's Spirit's job to tell Boeing what needs to be entered into CMES. Long quote:

Presented with evidence of their malfeasance, Spirit reopens the package and admits that not only did they not rework the rivets properly, there is a damaged pressure seal they need to replace (who damaged it, and when it was damaged is not clear to me). The big deal with this seal, at least according to frantic SAT postings, is the part is not on hand, and will need to be ordered, which is going to impact schedule, and (reading between the lines here) Management is Not Happy.

However, more critical for purposes of the accident investigation, the pressure seal is unsurprisingly sandwiched between the plug and the fuselage, and you cannot replace it without opening the door plug to gain access. All of this conversation is documented in increasingly aggressive posts in the SAT, but 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.

Finally with Spirit completing their work to Boeing QAs satisfaction, the two rivet-related records in CMES are stamped complete, and the SAT closed on 19 September 2023. No record or comment regarding the retention bolts is made.

I told you it was stupid.
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Old 24th Jan 2024, 04:25
  #1294 (permalink)  
 
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Originally Posted by MechEngr
This is true. What is also true is Spirit should have their own system for tracking work that should parallel CMES. Still, they did not formally alert Boeing that additional work needed to be entered into CMES to reflect the additional defect.
Originally Posted by remi
How would anyone know that they formally alerted Boeing or anyone else? Is there any system of record more sophisticated than email or typed letters that documents that? Is there any mechanism that makes such communication "official" rather than "discussion"?

There are countless memos from management and engineers found in boxes of discovery material that have led to awards to plaintiffs, but pretty close to zero such memos result in regulatory action beforehand.
Everybody in aerospace has some kind of quality management system, and in general workers from any particular company are going to do work on their own paper, even if it's at a customer facility. Part of everybody's quality system is how non-conformances get communicated back and forth - customer (Boeing) notes a non-conformance with the plug bolts. That non-conformance is now tied to that fuselage and it doesn't get accepted with it open. So Spirit generates a non-conformance in *their* system (probably attaching Boeing's documentation of it) and generates a repair or rework order. Their people do the work on a Spirit work order, which may or may not require inspection. Then the confirmation that the work was done gets transmitted to Boeing, where someone reviews it and attaches it to the NC that was written up by Boeing QA. It may or may not trigger an inspection (apparently didn't in this case) and someone at Boeing has to close on the NC. But since Spirit discovered the problem with the seal in the course of the work, they probably generated an additional NC for that, which may not have required someone from Boeing to disposition, but which they probably were required to report up to Boeing. That probably should have triggered an inspection - maybe it would have if it had started with an NC noted by Boeing rather than Spirit.

All of the sequence above is a guess - I've never worked at or with Boeing, but have worked with a lot of other companies, and the process is similar everywhere. Everybody works on their own documentation, and the non-conformances and inspection evidence gets passed up and down the chain and attached to the part records at every step. We can be pretty sure that it works like that at Boeing because that would be how the anonymous Boeing person could tell the story (assuming it's true). It's all there in the documentation system. They probably even know the names of who did the work, though it really doesn't matter. It's a system failure for one reason or another, and the goal is to make it harder to make mistakes, not punish people for making them. People make lots of mistakes, you build knowledge of that into the system, and you don't let them get away from you. (as an aside, a distinction with a config management system for building stuff like airplanes vs. software is that for airplane builds the computers are live humans with all their foibles and they're running work orders by hand)

I do like the suggestions that it might have resulted from terminology confusion. I couldn't get multiquote to include enough quotes, but I had been thinking that it was related to interpretation of the word "remove" rather than "door". But either way, those kinds of things happen all too much. You have the best process in the world that works great for years. Then you hire a new tech, maybe even someone very experienced but in a different part of aerospace so they're unfamiliar with the local terminology. They dutifully follow the procedure as carefully as possible and completely break something. It's not their fault, and I've seen it happen more than once. It's a function of not realizing how much specialized terminology you use in your day to day life - it's just normal language to you and everybody you work with. But it's from another planet for the new tech.
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Old 24th Jan 2024, 04:32
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Originally Posted by OldnGrounded
Exclusive: Boeing presses suppliers on tightening bolts after loose parts found in 737 MAX 9 checks

"[. . .]
Alaska Airlines CEO Ben Minicucci said in an NBC News interview that aired Tuesday that the airline found 'some loose bolts on many' MAX 9s during inspections.

'My demand on Boeing is, what are they going to do to improve their quality programs in house?' Minicucci said."
What more straightforward task is there than verifying that bolts of the correct specs are (existing) in the right holes torqued to the right force? Sure, if you can't get to them, maybe not so simple. But let's assume they are right in front of you, like we've seen in the photographs of the structure in question.

This seems to be a failure on the order of a checkbox is missing and/or no one checked the checkbox. After several hundred airframes, no one noticed this? Or did people exploit the fact that it was missing or a common practice to ignore it? And if so, what other kind of work does Boeing (or Spirit) do this way.

Alaska painfully internally reworked itself following the first and one of the extremely rare US multiple fatality scheduled carrier accidents of the new millennium (so far), for which it was primarily at fault. After 24 years of exemplary safety afterward, Alaska has a near fatal accident entirely not of its own making.

If I were the CEO of that company, I would be thinking, at Boeing management: "We did what we had to. We f-ed up. Change was uncomfortable and a lot of work but as a result we're doing great now. Exactly what have you, our only aircraft vendor, upon whom we are dependent on every matter of safety out of our own control, been doing?"

Last edited by remi; 24th Jan 2024 at 04:44.
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Old 24th Jan 2024, 06:15
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Originally Posted by OldnGrounded
United Chief Executive Scott Kirby said during the airline’s earnings call on Tuesday that it wasn’t canceling its orders for the Max 10. But he said the airline was taking the jet “out of our internal plans.”

“We’ll be working on what that means exactly with Boeing,” he said. “But Boeing is not going to be able to meet their contractual deliveries on at least many of those airplanes.”
Translated in common language:
We don't cancel the order just yet, because we would have to pay contractual penalties. So we are waiting for Boeing to acknowledge that they cannot fulfill their contractual obligations, so that we can cancel for free.

Originally Posted by remi
How would anyone know that they formally alerted Boeing or anyone else? Is there any system of record more sophisticated than email or typed letters that documents that? Is there any mechanism that makes such communication "official" rather than "discussion"?

There are countless memos from management and engineers found in boxes of discovery material that have led to awards to plaintiffs, but pretty close to zero such memos result in regulatory action beforehand.
It's a feature of such processes, that the supplier closes their books when the intermediate product is delivered to the OEM, so Spirit should not be able to add any tasks to their flavor of "CMES" after the fuselage has arrived in Renton. Any work being done there is under the flag of Boeing and reimbursement is up to accountants and their commercial book keeping for warranty claims.
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Old 24th Jan 2024, 06:29
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Originally Posted by C2H5OH
Translated in common language:
It's a feature of such processes, that the supplier closes their books when the intermediate product is delivered to the OEM, so Spirit should not be able to add any tasks to their flavor of "CMES" after the fuselage has arrived in Renton. Any work being done there is under the flag of Boeing and reimbursement is up to accountants and their commercial book keeping for warranty claims.
Physical location doesn't necessarily correlate with acceptance, and delivery doesn't necessarily lock a record. In other parts of aerospace it's not unusual for something to get delivered to the customer for tests that the supplier can't carry out themselves and acceptance only happens long after the item is physically with the customer. Rework/Repair/modification on a part can happen years after delivery and acceptance and the CM system should be able to tie the changes to the original record. It's not necessarily a common thing, but it's not unusual, either.
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Old 24th Jan 2024, 07:13
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Originally Posted by C2H5OH
Translated in common language:
It's a feature of such processes, that the supplier closes their books when the intermediate product is delivered to the OEM, so Spirit should not be able to add any tasks to their flavor of "CMES" after the fuselage has arrived in Renton. Any work being done there is under the flag of Boeing and reimbursement is up to accountants and their commercial book keeping for warranty claims.
Right, but my understanding is that there are Spirit personnel on site at the Renton assembly facility that are there to represent/facilitate/?? Spirit-the-vendor in some manner. I don't have any direct knowledge of this and my reading of previous comments may be incorrect or confused. (However, I was just at IKEA in Renton today. The checkout situation is even worse than its previously optimized-for-worst configuration. An omen?) Anyway, what do these Spirit people do? How do they communicate? Is it like that weird game of telephone I used to play with Indian engineers and their managers?

Me (X): I found XYZ and here's what to do
My manager: Good evening.
Indian manager: How are you?
Indian engineer: I read the email from X and he is absolutely right.
Indian manager: I'm well. And you?
My manager: Well, thank you. It's raining here.
Me: Mmm.
(This is literally four people on one phone call. Yes this is how these calls went. At 9PM my time.)

I've done a fair bit of consulting work but in general my customers have gone out of their way to give me as much access to communication, configuration management, etc., as possible. I can see how for CYA and BTV (blame the vendor) purposes it could be handy to have vendor representatives hanging around unable to do anything other than get sodas from the fridge.

I do genuinely wonder what the vendor reps are there for if they are not functionally integrated into the quality process.
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Old 24th Jan 2024, 07:26
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Throwaways' description makes perfect sense and like me many of us with knowledge of ISO and other QMS type systems probably had their face in their hands - its a classic. Yes, in the first instance the ship should have been delivered defect free but given the situation BAC found themselves in what should have happened is that the spirit warranty/re-work team should have been employed under contract arrangements that permitted them to use CMES even if through a designated BAC employee. There is so much more around culture and enforcement but we are not even close to that yet.
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Old 24th Jan 2024, 07:28
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Originally Posted by remi

I do genuinely wonder what the vendor reps are there for if they are not functionally integrated into the quality process.
From what I read, they are there, to fix warranty claims on the cheap for and under the commercial control of the supplier - but under the supervision and technical control of the OEM.
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