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Alaska Airlines flight 1282 NTSB preliminary report [pdf]

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Re: Alaska Airlines flight 1282 NTSB preliminary report [pdf]

#121

Post by fcsp »

koyote wrote: post #108
krona wrote: post #14

Earlier quoted context omitted.

> How did this pass Boeing QA? https://www.airlinepilotforums.com/safety/146074-boeing-inte...

So were the bolts missing because the Spirit team did not know they had to be put back (i.e. it was not recorded as a task that needed to be done) or was that simply just another mistake in the long line of mistakes they've made? Reading through that post gave me nightmares of dealing with outsourcing software teams where you send them a small issue to fix and their fix breaks 3 existing items.

As things stand, it seems the anon insider report from 3 weeks back was legitimate and accurate, and holds answers to your question: https://leehamnews.com/2024/01/15/unplanned-removal-installa...

Re: Alaska Airlines flight 1282 NTSB preliminary report [pdf]

#122

Post by mihaaly »

What is the analogy of leaving out all bolts from that door?

'Forgetting' to put in any of the screws holding a gas tank in place in a car?

'Missing' all welds in one of a skyscraper's lower columns?

An 'oversight' of providing rendundant instruments in an airplane with natural tendency to stall?

What a hopeless shitshow is going on there behind the company gates that these kind of things can happen in succession?

A duck forgot how to swimm, an eagle forgot how to fly, Boieing forgot how to build airplanes?

Re: Alaska Airlines flight 1282 NTSB preliminary report [pdf]

#123

Post by TillE »

imoverclocked wrote: post #43
mcmatterson wrote: post #3

The fact that a critical piece of the evidence was cell phone photos sent between workers coordinating door re-assembly doesn't exactly instill a whole lot of confidence in their permit-to-work process. I didn't like it when it was medical teams doing shift handover via a Google Doc, and I don't like it when it's a matter of flight safety either. Or, as Homer might eruditely say: "guess I forgot to put the bolts back…

> The investigation continues to determine what manufacturing documents were used to authorize the opening and closing of the left MED plug during the rivet rework. I mean, there is already a ton of documentation and process surrounding the construction of an airplane. Adding more process doesn't safety make. Having a safety culture without the fear of retaliation, on the other hand, makes a world of difference.

That line stood out to me, because it implies that no proper "manufacturing document" was used for the work. If that's true, that's very bad; unapproved maintenance procedures have been the cause of multiple crashes.

Re: Alaska Airlines flight 1282 NTSB preliminary report [pdf]

#124

Post by ethbr1 »

shadowgovt wrote: post #101
gtmitchell wrote: post #55

A very thorough preliminary report. I've worked for a long time in quality systems, and this is a perfect example of a systemic failure. They've got work being handed off between Boeing employees and 3rd party contractors with insufficient controls in place to verify that very basic tasks are being performed. I'd be curious to know how many non-conformances they typically see during assembly of a plane and whether ma…

Rumor has it the controls are there, but subvert-able. Apparently, there are two ticketing systems (one for "history of plane," Boeing internal, and one for "day-to-day onsite work," visible by contractors and Boeing management). The work to fix the rivets was logged in the day-to-day, but management and the onsite staff managed to convince themselves that merely opening the plug to fix the vacuum-seal trim did not c…

You might want to cite your source on this, which I'm guessing is the purported insider speaking about same?

From the portions of the report that hint at corroboration,

> Documents and photos show that to perform the replacement of the damaged rivets, access to the rivets required opening the left MED plug (see figure 15). To open the MED plug, the two vertical movement arrestor bolts and two upper guide track bolts had to be removed.

> Records show the rivets were replaced per engineering requirements on Non-Conformance (NC) Order 145-8987-RSHK-1296-002NC completed on September 19, 2023, by Spirit AeroSystems personnel. Photo documentation obtained from Boeing shows evidence of the left-hand MED plug closed with no retention hardware (bolts) in the three visible locations (the aft upper guide track is covered with insulation and cannot be seen in the photo)

Re: Alaska Airlines flight 1282 NTSB preliminary report [pdf]

#125

Post by rootusrootus »

SoftTalker wrote: post #110
rootusrootus wrote: post #80

Earlier quoted context omitted.

A minute is a long time when you're sitting at your computer. But after the sudden depressurization, I imagine the pilot is focused first on making sure he has complete control of the airplane, assessing the situation, running checklists. Besides, 10K is just barely above the normal pressurization altitude anyway, it doesn't pose an immediate risk to the passengers that justifies just nosediving towards the ground. E…

First and most importantly the pilots have to get their own oxygen masks on, if they delay this at all they will become hypoxic, unable to think clearly, then pass out, and then it's over for all on board.

Agreed, this is definitely the first order of business. Similarly for passengers, always put your own mask on first before helping anyone else near you. Can't help if you pass out.

Re: Alaska Airlines flight 1282 NTSB preliminary report [pdf]

#126

Post by toast0 »

cezart wrote: post #117
lp4vn wrote: post #97

Earlier quoted context omitted.

>I'd be curious to know [...] whether management is actually allowing the quality department sufficient independence to investigate these issues and fully resolve them If management in the aerospace industry works like management in the software industry, then I guess they are pushing for results as agressively as possible without much concern about safety or anything else.

At a company I worked in, we had a joke about this: "Good thing we don't build nuclear reactors". In some software projects the level of rush, and the fact that bugs sometimes would leak into production was kinda horrifying. It would've been way more so, if it would've been the kind of project that could kill people in case of failure. Like it happened in Chernobyl with nuclear reactors, or at Boeing with planes. I c…

Quality is always a trade-off. If you're deeply into economics, you wonder about the trade-offs of cost to find defects before shipping, difference in cost of addressing defects before and after shipping including costs of mitigation from consequences of defects, % of defects that will never be found after shipping (and are therefore a real cost savings), and in the long game costs of having a reputation for shipping product with defects that could have been reasonably detected.

In a lot of software organizations with rapidly changing and undocumented requirements, there's a good chance defects will go unnoticed until they're no longer relevant, so spending a lot to find them before they're shipped is a waste. Mitigation of many software defects is simple, but some aren't; hopefully you know which changes are expensive to fix if wrong, so you can more thoroughly vet those.

In Aerospace, addressing defects after shipping is very expensive, and mitigating the effects of defects is only approximate; you can't restore passengers from backup, economic damages don't really make families whole, but should be an incentive not to let reasonably detectable defects be shipped.

Re: Alaska Airlines flight 1282 NTSB preliminary report [pdf]

#127

Post by koyote »

fcsp wrote: post #121
koyote wrote: post #108

Earlier quoted context omitted.

So were the bolts missing because the Spirit team did not know they had to be put back (i.e. it was not recorded as a task that needed to be done) or was that simply just another mistake in the long line of mistakes they've made? Reading through that post gave me nightmares of dealing with outsourcing software teams where you send them a small issue to fix and their fix breaks 3 existing items.

As things stand, it seems the anon insider report from 3 weeks back was legitimate and accurate, and holds answers to your question: https://leehamnews.com/2024/01/15/unplanned-removal-installa...

I read that but could not work out which of my two statements are true. Might just be bad reading comprehension on my side...

Re: Alaska Airlines flight 1282 NTSB preliminary report [pdf]

#128

Post by mihaaly »

gtmitchell wrote: post #55

A very thorough preliminary report. I've worked for a long time in quality systems, and this is a perfect example of a systemic failure. They've got work being handed off between Boeing employees and 3rd party contractors with insufficient controls in place to verify that very basic tasks are being performed. I'd be curious to know how many non-conformances they typically see during assembly of a plane and whether ma…

I have tendency to hope for unrealistic things too. Not a reliable trait of mine, no. But in my clear moments I am afraid that much sooner will come the world peace and union of all nations and religions than unimaginative but determined bean counters learn from millions of catastrophes of the past and future to come giving up pushing their core value and first rule of 'take more, give less' into the infinity and beyond. And giving up their personal wealth with it.

Re: Alaska Airlines flight 1282 NTSB preliminary report [pdf]

#129

Post by aniftythrifrty »

gtmitchell wrote: post #55

A very thorough preliminary report. I've worked for a long time in quality systems, and this is a perfect example of a systemic failure. They've got work being handed off between Boeing employees and 3rd party contractors with insufficient controls in place to verify that very basic tasks are being performed. I'd be curious to know how many non-conformances they typically see during assembly of a plane and whether ma…

[flagged]

Re: Alaska Airlines flight 1282 NTSB preliminary report [pdf]

#130

Post by pests »

ceejayoz wrote: post #104
wkipling wrote: post #71

Earlier quoted context omitted.

Absolutely not. Body cams mute the first part of the audio for this exact reason. Privacy is important.

The issue with police body cam audio is that they are regularly recording non-police who do have a right to privacy. That's not an issue for pilot cockpit recordings. (If it is, you've got an incident that should be recorded.) The muting you observe of police footage isn't of the first part of the audio, it's the prior 30 seconds from before the record button is pressed. They have a constant buffer going, as things c…

> The muting you observe of police footage isn't of the first part of the audio, it's the prior 30 seconds from before the record button is pressed. They have a constant buffer going, as things can happen... unexpectedly.

I just want to clarify that it only buffers the video. The way you worded it still doesn't explain why the previous 30 seconds of audio isn't included in the buffering.

When the button is pressed is when audio recording is started and the previous 30 seconds of video buffer is prepended to the live recording.

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