[HN Gopher] Alaska Airlines flight 1282 NTSB preliminary report ...
___________________________________________________________________
Alaska Airlines flight 1282 NTSB preliminary report [pdf]
Author : tomalpha
Score : 120 points
Date : 2024-02-06 21:17 UTC (1 hours ago)
(HTM) web link (www.ntsb.gov)
(TXT) w3m dump (www.ntsb.gov)
| mef wrote:
| anyone have a copy hosted? it's currently overloaded and not
| responding
| hipadev23 wrote:
| I believe this video mostly covers it:
| https://youtu.be/3m5qxZm_JqM
| ilyagr wrote:
| This is old satire. It's good satire, but don't expect to
| find actual information here.
| geoffeg wrote:
| https://aviationsourcenews.com/wp-content/uploads/2024/02/Re...
| mcmatterson wrote:
| 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 in" [1]
|
| [1] (https://www.youtube.com/watch?v=IiNPLIauEig)
| gowings97 wrote:
| The data/photos should be in the ERP/MES.
| ipython wrote:
| This is a puzzling attitude to me. Every time we technologists
| see a crappy proprietary solution being used for a problem, the
| first exclamation is, "why not use <commodity solution X>?
| That's so dumb, they spent $10k on that tool when they could
| have spent $100 on X!"
|
| There must be a middle ground here- the paradox is that Google,
| Apple, etc have this ability to generate user friendly software
| and hardware at scale. But they aren't considered "battle
| proven". The expensive proprietary systems that are used
| instead tend to be hard to use and brittle, so what's the
| middle ground?
| michael1999 wrote:
| The issue here isn't using google chat, the accusation is
| that this was Spirit and Boeing conspiring to not record
| these in the proper work order system under the pretence that
| this work was being done by Spirit as-if-it-were pre-
| delivery.
|
| Read https://www.airlinepilotforums.com/safety/146074-boeing-
| inte...
|
| And then this from the doc: "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."
|
| https://s3.documentcloud.org/documents/24410269/report_dca24.
| ..
| imoverclocked wrote:
| > 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.
| TillE wrote:
| 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.
| spdustin wrote:
| Also posted on DocumentCloud, since NTSB servers aren't
| responding (as of this comment)
|
| https://s3.documentcloud.org/documents/24410269/report_dca24...
| guardiangod wrote:
| >[evidences] indicate that the four bolts that prevent upward
| movement of the MED plug were missing before the MED plug moved
| upward off the stop pads.
|
| Ok
|
| >Photos from the interior repair that show the lack of bolts
|
| Huh. Well that's conclusive.
| nostromo wrote:
| > Overall, the observed damage patterns and absence of contact
| damage or deformation around holes associated with the vertical
| movement arrestor bolts and upper guide track bolts in the upper
| guide fittings, hinge fittings, and recovered aft lower hinge
| guide fitting indicate that the four bolts that prevent upward
| movement of the MED plug were missing before the MED plug moved
| upward off the stop pads.
|
| Ooofff. No bolts at all! How did this pass Boeing QA?
| krona wrote:
| > How did this pass Boeing QA?
|
| https://www.airlinepilotforums.com/safety/146074-boeing-inte...
| jbverschoor wrote:
| Just comment out the tests and they pass
| belter wrote:
| Instead of Software Development becoming more like
| Aeronautical Engineering, every day, Aeronautical
| Engineering becomes more like Software Development...
| jiggawatts wrote:
| I'm trying to convince a group of devs that catching (and
| ignoring) every exception is not actually a solution to
| their crash bugs.
| jbverschoor wrote:
| Ya know.. you can also just do that and then change the
| requirements:
|
| > In a revision to the Flight Crew Operations Manual,
| issued on January 15, 2024, Boeing confirmed that the
| door functioned as designed.
|
| Problem solved for the current level in the hierarchy.
| function_seven wrote:
| Great link!
|
| I like how that comment is from an anonymous source, but now
| that the NTSB preliminary report is out, it seems thoroughly
| corroborated to me. The dates of certain events and the
| reason for the door's removal--er, "opening"--both match the
| comment in your link.
|
| Thanks.
| koyote wrote:
| 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.
| fcsp wrote:
| 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...
| __loam wrote:
| MBAs prioritizing the bottom line over engineering culture.
| newZWhoDis wrote:
| Seems to solidly confirm the leak.
| aftbit wrote:
| > The accident airplane was required to be equipped with a CVR
| that retained, at minimum, the last 2 hours of audio information,
| including flight crew communications and other sounds inside the
| cockpit.
|
| >The CVR was downloaded successfully; however, it was determined
| that the audio from the accident flight had been overwritten. The
| CVR circuit breaker had not been manually deactivated after the
| airplane landed following the accident in time to preserve the
| accident flight recording.
|
| Classic. If they use CD quality audio at 1411kbps, they can store
| 2 hours of audio in about 1.2 GB. Given how cheap flash is these
| days, why not 20x that so that we don't have to rely on people
| pulling circuit breakers after accidents? If there's some concern
| about robustness and recertification, why not require all
| aircraft to carry two CVRs, one of the old "robust" style for
| kinetic accidents, and one that's less robust but has 20x the
| capacity, so we can record a full day after less violent
| accidents?
| cjbprime wrote:
| The largest US pilots union opposes it on pilot privacy
| grounds. (To be clear, I think having an expectation of vocal
| privacy while you are in charge of an airliner is absurd.)
| ekianjo wrote:
| Yet people on HN love unions so that just can't be the real
| problem
| gruez wrote:
| HN isn't a monolith, and it certainly has better
| representation of anti-union sentiment (ie. they don't all
| get downvoted to oblivion) compared to other discussion
| forums (eg. reddit).
| cjbprime wrote:
| I (person who blamed the pilots union above) actually like
| unions. I could probably even say good things about pilot
| unions; I would say that part of the reason US airlines
| have fewer accidents than some other wealthy countries is
| the effect the unions have had on resisting attempts to
| work pilots through dangerous levels of fatigue, and on
| ensuring pilots can report dangerous situations and have
| them comprehensively fixed without retaliation.
|
| I don't have faith in "market forces" to do those things,
| and consider the state of aviation in some other countries
| to be a living experiment showing why.
|
| The opposition to cockpit recording is bonkers, though.
| CPLX wrote:
| Do you have a voice recording of you doing your entire job,
| every day of your life?
| csdreamer7 wrote:
| There are software engineer jobs where you need to keep
| your camera on during work hours to show you are in your
| seat.
| andy81 wrote:
| Yeah, but nobody applies for those.
| zorpner wrote:
| These jobs do not attract the best software engineers.
| lotsofpulp wrote:
| They could with sufficient pay.
| irrational wrote:
| I'm pretty sure any place doing that is not going to
| offer sufficient pay.
| sokoloff wrote:
| The intersection between employers who demand to film you
| being in a chair and employers who shower their employees
| with substantial lucre is the null set.
| Hamuko wrote:
| I doubt the jobs where you don't enjoy any level of trust
| are the ones where you get paid well or get any kind of
| dignified treatment.
|
| I recently saw a job ad for a JavaScript specialist where
| the position entailed having screenshots and keyboard +
| mouse tracking to monitor your working hours. It was a
| freelancer position, so the hire would handle taxes and
| health insurance, no equipment would be provided and
| working hours would start at 08:00 German time sharp for
| at least nine hours or until you "finish the daily
| tasks". Pay would however be for 189 hours per month, no
| compensation for sick leave/holidays/vacation, and you'd
| be paid via upwork.com (with you paying Upwork's fees) in
| US dollars.
| breadwinner wrote:
| If my job involved taking the lives of hundreds of humans
| in my hands, then I would expect that, at least during the
| hours in which said lives are my responsibility.
| jiggawatts wrote:
| IMHO surgical theatres should have permanent multi-
| perspective cameras recording everything for the same
| reason.
| doikor wrote:
| There you also have patient privacy to take into account.
| hn8305823 wrote:
| Only if the patient consents (or their family if they are
| unable to give legal consent), otherwise no for patient
| privacy.
| bagels wrote:
| Hundreds of people don't die when I screw up.
| RandomBK wrote:
| My job does not involve direct responsibility for the
| immediate life-or-death of hundreds of lives.
| kesslern wrote:
| This is the reality for a large number of truck drivers who
| bear a significantly lower responsibility.
| WheatMillington wrote:
| No but I also don't have the lives of 300 people in my
| hands.
| Hamuko wrote:
| Pilots can have the lives of quite a lot more than that
| on their hands since an airplane makes for a great
| kinetic weapon. The pilots of KLM Flight 4805 took the
| lives of almost 600 people.
| UberFly wrote:
| Many people do. Depends on the job.
| ryanmcbride wrote:
| I did when I worked retail, and while I worked food
| service.
| sterlind wrote:
| No, but I'm also not driving hundreds of souls around near
| mach 1 strapped to 100k gallons of jet fuel. And when I've
| worked in government environments I had escorts watching my
| screen like a hawk the entire time.
|
| Not to mention the tapes are only pulled if there's an
| incident. You could even have a little tamper seal on it to
| show if it's been downloaded. This is absurd.
| RankingMember wrote:
| See also: police bodycams
|
| If you have the capacity to end peoples' lives with an
| arm spasm I think your privacy should rightfully take a
| backseat.
| wkipling wrote:
| Absolutely not. Body cams mute the first part of the
| audio for this exact reason. Privacy is important.
| ceejayoz wrote:
| 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 can happen...
| unexpectedly.
|
| This caught a cop in Baltimore; he wasn't aware of or had
| forgotten the feature. The 30 second buffer caught him
| planting drugs, then faking the finding.
| https://www.npr.org/sections/thetwo-
| way/2017/07/20/538279258...
|
| Side note: It took years to charge him
| (https://www.baltimoresun.com/2020/03/09/caught-
| fabricating-e...) and he served no jail time for trying
| to send an innocent person to jail
| (https://www.wbaltv.com/article/officer-testifies-in-own-
| defe...).
| pants2 wrote:
| Well, I do have a Git repo that tracks every meaningful
| change and action that I've done at my job since inception.
| imoverclocked wrote:
| Well, there is the theory and then there is the reality.
|
| Theory: having less privacy makes things easier for accident
| investigators, post-mortem.
|
| Reality: In this case, the pilots did their job and got the
| plane down safely despite rapid depressurization and
| literally having their headsets sucked off of their heads. It
| is extremely unlikely to be pilot-error that a door-plug
| ripped off the airframe at 16,000' or that investigators
| would learn anything significant from the process in the
| flight-deck before or after the incident. At least nothing
| that would root-cause this incident.
| lotsofpulp wrote:
| Your comment would only make sense if your example of
| reality showed the theory was flawed. However, your example
| of reality is unrelated to the theory, so not sure what
| your point is.
| crznp wrote:
| That is a non-sequitur. Investigators should have access to
| accident data regardless of whether the pilots did their
| job.
|
| Root cause analysis isn't the only reason: it would be good
| for pilots to have this case study, as well as analysis on
| how systems responded to the abrupt change.
|
| Having this data is strictly better than not having it.
| hencq wrote:
| I think there's some validity to the privacy concerns, but it
| seems those could be addressed with proper access controls
| and rules. The recordings should only really be listened to
| in the aftermath of an accident, in which case, as you say,
| the expectation of privacy should (in my opinion) take a
| backseat.
| rantingdemon wrote:
| Indeed. Pretty much all your communication is recorded at
| any company you work for anyway.
| DiggyJohnson wrote:
| My work does not have a recording of most of my verbal
| communication in office, and it's a very secure site and
| project.
| zer00eyz wrote:
| On one hand I agree with you.
|
| On the other hand, if someone recored my whole work day
| every day I would not be happy. I don't think you would
| stay at your job of that was a condition of it.
|
| There has to be a better solution to this issue.. extended
| recordings in an emergency, triggers based on conditions,
| private keys for pilots... IDFK, cause I try not to get
| involved in engineering that might KILL someone.
| cjbprime wrote:
| I don't understand. Are you implying that recording a
| pilot's voice for more than two hours could kill someone?
| Or just that aviation is stressful and high stakes?
|
| (I agree that it's stressful and high stakes, which is
| why we record it.)
| DiggyJohnson wrote:
| Why not? Do you think other engineers are better suited
| for such work?
|
| I'm just curious, because I personally work on things
| that could kill people directly or indirectly.
| pests wrote:
| > if someone recored my whole work day every day I would
| not be happy
|
| Maybe people live with this reality every day already.
| Remote workers with screen sharing software, certs
| installed so companies can spy on everything you do,
| retail workers under cameras all day.
| salad-tycoon wrote:
| My wife ridicules me because when we went out to eat, before
| a multitude of children , I would often say "nobody ever
| tipped me as a meat clerk when I was working in 45 degrees
| elbows deep throwing away and scraping rotting meat from the
| shelves and gutters and then serving 'fresh shrimp ' and
| organic grass fed filet mignon" when I felt expected to tip
| 20% for an already over priced meal.
|
| As my first boss, meat clerk young lady, told me "shit rolls
| down hill." More powerful people tend to get shitted on less.
| It was a motivation to move up.
|
| But I still think it's shitting on people to expect or accept
| constant recording of everything mundane thing while awaiting
| the exceptional [screw up]. Pilots are more powerful than
| Amazon warehouse workers but recording every breath, every
| whisper, ever fart is undoubtedly shit in a warehouse or a
| cockpit or an operating room.
|
| Then again, the only way I could accept it is if everyone is
| recorded all the time and it was all public or at least FOIA
| able for many people. Especially the government and
| universities and Wall Street other wise it's just a way to
| control and hang things over peoples heads.
|
| As to the tipping grumpiness I grew up partly in the 3rd
| world where tipping 50 cents was a great tip and I'm cheap
| and didn't/don't make tech bro money. I found the ultimate
| solution was to just not eat out so much except for truly
| special occasions. I'm sure there's a lesson in there too
| somewhere.
| zardo wrote:
| Privacy from an NTSB accident investigation is absurd.
| Privacy from your boss snooping you is reasonable.
| SilasX wrote:
| Reminds me of an exchange from Stranger Things (S4E3):
|
| School counselor: Max, I'm... I'm sorry, I... I really can't
| discuss this. You wouldn't want me talking to any other
| students about _you_ , right?
|
| Max: If I were dead and it would help catch the killer, then
| yeah, I most definitely would.
|
| https://subslikescript.com/series/Stranger_Things-4574334/se.
| ..
| dmitrygr wrote:
| > Given how cheap flash is these days
|
| How cheap is flash that will survive a sudden stop from 400mph
| to 0 mph in no seconds flat, will survive a post-crash fire,
| and/or submersion for years in salt water?
|
| Flash data retention at high temps is TERRIBLE (and gets worse
| for MLC/TLC/etc), see any flash datasheet. It is NOT nearly as
| simple a problem as you might think.
|
| Yes, it is a solvable problem, but please do not dismiss it so
| outright as "trivial"
| N19PEDL2 wrote:
| Read it more carefully.
| ammar2 wrote:
| This isn't a technical limitation though, the European
| standard for airplanes newer than 2021 is in fact 25 hours
| [1].
|
| [1] https://mentourpilot.com/who-doesnt-want-25-hour-cockpit-
| voi...
| margalabargala wrote:
| I don't think the problem you're describing is actually a
| problem.
|
| Exposure to super-high temps occurs in a small set of
| circumstances, all of which overlap with the destruction of
| the recording device and the cessation of incoming data. So
| we only need the same 1.2GB (or whatever) of high-
| temperature-tolerant storage.
|
| The 25 hour storage can be on normal flash, as if we're more
| than 2 hours past the incident and data is continuing to come
| in, then the incident of interest did not destroy the
| airplane, and the flash will have remained within its normal
| operating parameters.
| dmitrygr wrote:
| Multiple investigations in the past have recovered data
| from FDR and/or CVR after an extensive high-temperature
| fire. I do not think that FAA will give that requirement
| up.
| margalabargala wrote:
| Yes. As I said. The existing system can remain in place,
| with all of its existing high-temperature-tolerant
| components.
|
| In addition to not giving up that requirement, we could
| also add a longer, not-heat-tolerant storage. If it gets
| destroyed in a fire, see the above paragraph. If there is
| an incident where the data is of interest and the
| aircraft is not destroyed in a fire, then this will
| maintain the data long after the above system has deleted
| it.
|
| No one has advocated giving up the high temperate
| storage.
| antisthenes wrote:
| What you described is not a data retention problem at all.
|
| It's a material science problem, and other forms of media are
| affected by high temperatures and physical deformation just
| as much as flash if not more.
| bronco21016 wrote:
| What's missing from this accident investigation without the
| recording?
| blantonl wrote:
| ability to somehow claim pilot error. That's what.
| sigwinch28 wrote:
| The rule (edit: in Europe) is now 25 hours for aircraft over a
| certain weight, though it is not (currently) retroactively
| applied to existing equipment.
|
| https://www.federalregister.gov/documents/2023/12/04/2023-26...
| cjbprime wrote:
| That document is an in-progress proposal to amend a rule, no?
| I think there was strong opposition to this rule before this
| accident flight, and the blowback from the missing data here
| might be strong enough to be able to get it passed anyway.
| sigwinch28 wrote:
| It is the rule in Europe, which is mentioned in (II)(C) in
| the link. I failed to link it properly.
| imoverclocked wrote:
| > the blowback from the missing data here might be strong
| enough to be able to get it passed anyway
|
| Nice pun.
|
| What do you think would have been gained from the CVR data
| in this case? Do you think pilot error had anything to do
| with the door-plug failure? Do you think the CVR was left
| running on purpose/accident?
|
| If I were one of those pilots, the first words out of my
| mouth probably would have been, "what the $&#*?!" followed
| by whatever procedure had been drilled into me for rapid-
| depressurization. Given the scenario, I wouldn't lose any
| sleep over forgetting to shutoff the CVR in the mess of
| getting everyone to safety.
| cjbprime wrote:
| I'm not an accident investigator and don't know what
| exactly would turn out to be useful, but I think changing
| your intuition for why we study the CVR away from
| "because there might have been a large pilot error" to
| "so that we can learn more about how pilots react to
| emergencies with a goal of seeing if we can come up with
| process improvements" may help. If there _was_ some
| aspect of the response that was not perfect, we could
| develop training on it for other pilots, right?
| imoverclocked wrote:
| That's not what is at stake here though. CVRs are not
| intended for improving process like a call-center
| recorded line. "Both recorders are installed to help
| reconstruct the events leading to an aircraft accident."
| [ntsb.gov]
|
| This creep of intended-use is exactly why many people
| oppose surveillance in the first place.
| gruez wrote:
| >ACTION:
|
| >Notice of proposed rulemaking (NPRM).
|
| >[...]
|
| >DATES:
|
| >Send comments on or before February 2, 2024.
|
| Seems like it's a proposal, and not actually enacted yet?
| the_mitsuhiko wrote:
| It was enacted in 2021 for some aircrafts. Not sure what
| the change of that proposal is, might expand it to more.
| jbverschoor wrote:
| > In a revision to the Flight Crew Operations Manual, issued on
| January 15, 2024, Boeing confirmed that the door functioned as
| designed.
|
| Smells like CISCO
| aftbit wrote:
| Depressurization happened around 17:12:33 PST but the aircraft
| continued to climb until 17:13:41 PST, and the autopilot was
| configured for 10k ft at 17:13:56 PST. Why did it take the pilots
| a full minute to begin an emergency descent after the failure? I
| would expect that the nature of the accident would be clear
| nearly immediately, at least in the need to descend the aircraft.
| throwworhtthrow wrote:
| You can't leave your assigned altitude/trajectory without
| coordinating with ATC. Otherwise you may collide with another
| plane, which would make a bad situation worse.
| mazugrin2 wrote:
| Sure you can, and they likely did start descending before
| contacting ATC. But before they did any of that, they had to
| spend some time donning their oxygen masks and doing a few
| other "memory items" before then descending.
| michaelt wrote:
| In this instance the report explicitly says:-
|
| _> Both flight crew said they immediately donned their
| oxygen masks. They added that the flight deck door was
| blown open and that it was very noisy and difficult to
| communicate.
|
| > The flight crew immediately contacted air traffic control
| (ATC), declared an emergency, and requested a lower
| altitude. The flight was assigned 10,000 ft. The captain
| said he then requested the rapid decompression checklist,
| and the FO executed the required checklist from the Quick
| Reference Handbook (QRH). As the FO completed the
| checklist, the captain flew the airplane as they
| coordinated with ATC to return to the PDX airport. The
| flight landed on runway 28L without further incident and
| taxied to the gate._
|
| So in this particular instance, when the depressurisation
| happened at a comparatively low altitude, the pilots did
| get ATC clearance before descending.
| lisper wrote:
| In an emergency you can do anything you think is necessary to
| address it. Source: I'm a private pilot.
| zer0x4d wrote:
| You're conflating the right to do something with whether it
| is advisable to do something.
|
| Sure, you are ~allowed~ to begin an immediate descent in an
| emergency, but it is not a good idea considering from the
| pilot's perspective, the bang is most likely an engine
| going out and altitude is always your friend in this
| condition.
| luizfzs wrote:
| Also, running checklists for specific types of emergencies.
| 16bytes wrote:
| Aviate comes before navigate and communicate. The pilot in
| charge is ultimately responsible for the safety of the
| aircraft, not ATC.
| bronco21016 wrote:
| Step one is to put on the oxygen mask and establish
| communications. After the startle factor, the masks being put
| on, then declaring an emergency, a minute really isn't that
| long.
| sigwinch28 wrote:
| More altitude means more time to work the problem.
| blantonl wrote:
| _I would expect that the nature of the accident would be clear
| nearly immediately_
|
| Not really. The cockpit door was blown open, and the pilot's
| headsets were blown off. It was a pretty chaotic event, and
| when you are flying an airplane, you definitely don't want to
| figuratively "jerk the wheel" - you remain calm and start
| running checklists.
| rootusrootus wrote:
| 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. Especially
| given how much air traffic is at lower altitudes that close to
| PDX.
|
| Edit: Re-reading, it was more like 16K feet when it popped, 10K
| is what ATC assigned them when requested. Still low enough not
| to be a critical emergency. Some people absolutely will get
| altitude sickness at that level, but it's likely to be mild.
| Many people climb mountains much taller.
| SoftTalker wrote:
| 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.
| bagels wrote:
| Clearance + they were probably putting on their masks, and
| other tasks.
| engcoach wrote:
| Fast hands in the cockpit are scary. Pilots take their time in
| emergencies because rushing will take your birthday away
| michaelt wrote:
| According to the plane's "memory items" [1] in response to a
| cabin altitude warning or rapid depressurization, pilots must:
|
| OXYGEN MASKS - DON
|
| OXYGEN REGULATORS - Set to 100%
|
| CREW COMMUNICATIONS - ESTABLISH
|
| PRESSURIZATION MODE SELECTOR - MAN AC/MAN
|
| OUTFLOW VALVE SWITCH - CLOSE
|
| Hold in CLOSE until outflow Valve indicates fully closed
|
| If Pressurization is Not Controllable
|
| PASSENGER SIGNS - ON
|
| PASSENGER OXYGEN SWITCH - ON
|
| EMERGENCY DESCENT - ANNOUNCE
|
| The pilot flying will advise the cabin crew, on PA system, of
| impending rapid descent. The pilot monitoring will advise ATC
| and obtain area altimeter setting.
|
| PASSENGERS SIGN - ON
|
| DESCENT - INITIATE
|
| I do giggle a little at the thought of a door flying off, the
| air rushing out of the cabin, and the pilots responding by
| switching the seatbelt light on.
|
| The plane was only at 16,000 feet when it lost its door and
| according to [2] you've got 20-30 minutes of 'useful
| consciousness' at such an altitude, even without your oxygen
| mask on. So there was no need for an abrupt dive.
|
| [1]
| https://www.theairlinepilots.com/forumarchive/b737/b737memor...
| [2] https://skybrary.aero/articles/time-useful-consciousness
| dzdt wrote:
| The report seems to mesh with and confirm many details of the
| anonymous insider account at
| https://leehamnews.com/2024/01/15/unplanned-removal-installa....
| The bolts were not reinstalled following work on the plug
| rivets/seal. The official system doesn't record that work was
| done requiring the bolts to be removed.
| belltaco wrote:
| >The CVR was downloaded successfully; however, it was determined
| that the audio from the accident flight had been overwritten. The
| CVR circuit breaker had not been manually deactivated after the
| airplane landed following the accident in time to preserve the
| accident flight recording
|
| In addition to local storage, why isn't the audio(along with
| location, altitude and some sensor information) also streamed
| using something like Starlink or Inmarsat to a secure location
| where you can store more data for cheaper and with more
| redundancy?
| sv123 wrote:
| $$$
| skywhopper wrote:
| This is an old system that works well and reliably for pretty
| much every incident. I'm not aware of another case of this sort
| of thing (relevant flight recorder data being overwritten)
| happening in recent years anyway. If you spend time constantly
| upgrading systems like this you're asking for a higher failure
| rate, for very little gain.
|
| That said, there's a standard and reliable 25-hour flight voice
| recorder that solves this problem. But it's only used outside
| the US. That's a regulatory inertia situation and I suspect
| this incident will speed changes in this area.
|
| However, finally, and particularly in relation to your proposal
| of streaming cockpit voice recordings to some cloud server.
| There is some resistance to this (and to longer recordings in
| general) from air crew on privacy grounds. The privacy issue is
| less about how much personal info is revealed in a crash
| situation and more about how easy it would be for a bad actor
| in management --or whatever operations group runs the audio
| storage--to listen in on conversations. And you can be sure
| this would happen if something like your system were
| implemented without the appropriate regulatory controls (and
| tbh even with them it would probably still happen).
| spdustin wrote:
| Looks like the anonymous whistleblower on Airline Pilot Central
| Forums [0] was legit.
|
| [0]: https://www.airlinepilotforums.com/safety/146074-boeing-
| inte...
| gtmitchell wrote:
| 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 management is actually
| allowing the quality department sufficient independence to
| investigate these issues and fully resolve them. I'm guessing
| that the production personnel are under tremendous time
| constraints and are constantly pressure the quality assurance
| people to sign off on whatever paperwork is holding up the line,
| no matter the safety implications.
|
| Also, I think a lot of middle and upper level management needs to
| lose their jobs over this. I hope this mess ends up in textbooks
| and gets beaten into the head of every MBA student in the
| country.
| lp4vn wrote:
| >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.
| cezart wrote:
| 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 can't really imagine what these engineers feel when they
| rush this kind of work knowing what's at stake.
| shadowgovt wrote:
| 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 constitute
| "removing" the plug, and since there was only an entry in the
| history-of-plane log for removing, not opening, they didn't log
| it there (when the intent was "there's no entry for 'just
| opening' because there's no such thing as 'just opening',
| _breaching the pressure vessel at all_ constitutes 'removal of
| plug'").
|
| The final inspection that should have caught the error would
| have been triggered by the update in the history-of-plane
| ticketing queue.
|
| (And as for 'how many non-conformances,' the same source claims
| that Spirit is one of the few subcontractors with on-site staff
| at the factory because their parent company delivers such
| consistently shoddy out-of-compliance product that they are
| continuously doing final warrenty-work onsite. So maybe "fire
| that vendor" should be on the docket too).
| ethbr1 wrote:
| You might want to cite your source on this, which I'm
| guessing is the purported insider speaking about same?
| onetimeuse92304 wrote:
| > I'd be curious to know how many non-conformances they
| typically see during assembly of a plane (...)
|
| Very likely that number is meaningless. I suspect this is the
| kind of environment that incentivises hiding non-conformances
| whenever possible.
|
| For example, better quality control usually results in an
| _increase_ of number of defects, at least temporarily. But that
| just because large portion of these defects were undetected
| before.
|
| So... you are looking at a number that you have nothing to
| compare to that also depends on how closely the process is
| monitored and also depends a lot on the definition of what is
| non-conformance.
|
| It is like trying to give an answer to "what is the length of
| Britain's coastline?" Everybody knows that you can get whatever
| answer you want depending on how long the ruler is.
| ultimoo wrote:
| I look forward to reading a report from NTSB's internet outage.
| Hansenq wrote:
| If people are looking for additional in-depth reading on how this
| happened, The Air Current did a great write-up on this systemic
| mistake using internal Boeing sources a month ago that the NTSB
| report fully supports: https://theaircurrent.com/aviation-
| safety/127-days-the-anato...
| hn8305823 wrote:
| I wonder how close the door plug was to hitting the tailplane or
| vertical stabilizer/rudder?
| reddit_clone wrote:
| Considering all those scary scenarios, what happened was
| probably the most favourable outcome. It could have been a
| major disaster hundred different ways..
| mikeyouse wrote:
| It sure could have -- the plane was still climbing which puts
| that plug door almost directly in line with the horizontal
| stabilizers;
|
| https://i.cbc.ca/1.7077373.1704733027!/fileImage/httpImage/g.
| ..
| WatchDog wrote:
| > The flight crew reported that the cockpit door had opened
| during the depressurization event. In a revision to the Flight
| Crew Operations Manual, issued on January 15, 2024, Boeing
| confirmed that the door functioned as designed.
|
| Interesting for terrorists. Cause a rapid decompression, and get
| easy access to the cockpit.
| mihaaly wrote:
| 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?
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(page generated 2024-02-06 23:00 UTC)