[HN Gopher] Smoke in the cabin of two 737 MAX caused by Load Red...
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Smoke in the cabin of two 737 MAX caused by Load Reduction Device
system [video]
Author : dz0ny
Score : 67 points
Date : 2025-02-09 22:12 UTC (2 days ago)
(HTM) web link (www.youtube.com)
(TXT) w3m dump (www.youtube.com)
| dz0ny wrote:
| This is a issue that may also affect Airbus aircraft, but so far,
| it has only caused problems on two Boeing planes. Like MCAS, it
| was not disclosed to pilots, prompting the FAA to recommend
| design changes and notify flight crews.
|
| https://simpleflying.com/boeing-cfm-international-update-737...
| K0balt wrote:
| Unfortunately, it seems that the internal FAA recommendations
| were not allowed to make their way into any kind of
| airworthiness directive.
|
| The recommendations include very basic procedure changes that
| mitigate the near term risks without any significant impact to
| operation, as well as recommendations for what probably amounts
| to a software change and upgrades to some of the pilot oxygen
| masks to effect a permanent fix.
|
| The only reason that we even know about the internal
| recommendations is that they were leaked to the press.
|
| Boeing released a pilot bulletin that basically says to go
| through the checklist quickly and to treat smoke in the cabin
| as a major failure, but stops short of recommending some very,
| very simple steps in aircraft configuration prior to takeoff
| that would completely mitigate the issue without negatively
| effecting flight performance.
|
| The major recommendation in the internal FAA bulletin is to use
| the APU bleed instead of the main engine bleed air to power the
| air conditioning and cabin pressurisation during the takeoff
| phase of flight, below 3000 feet AGL. I can see no reason to
| drag feet on this recommendation, other than the uncomfortable
| suggestion that perhaps this issue should have been addressed
| during certification. (It is yet another difference from older
| 737 design , like the deadly MCAS system, that was not
| disclosed to pilots transitioning to the new aircraft)
| berkut wrote:
| It's not clear that is does affect Airbus does it?
|
| It looks like only the LEAP-1b engines are affected by this,
| and I was under the impression that LEAP-1b was 737-MAX-only?
|
| (A320 has LEAP-1a as far as I can see).
| unsnap_biceps wrote:
| he covers this in the video, but both engines have the same
| LRD (Load reduction device), but it's more about how the
| bleed system is done on if it's an impact or not, and he
| doesn't know if the other planes have the same flaw or not.
| toomuchtodo wrote:
| "Load reduction device."
|
| https://www.airliners.net/forum/viewtopic.php?t=1497965
| hypothesis wrote:
| I wonder what was the thought process there: hey we save an
| engine maybe, but everyone inside the plane gets cooked in 39
| seconds. Ship it!
|
| Comments on that youtube video are filled with industry insiders
| and it's just wild. They even think someone has died from a
| similar fuming event back in December...
| Havoc wrote:
| Maybe they were thinking the Russian solution. If it crashes
| fast enough nobody finds out what happened
| K0balt wrote:
| It doesn't save the engine, it keeps it from ripping the wing
| off. It's a good system.
|
| The part about filling the cabin with smoke because they
| couldn't be bothered to make the software that detects the
| extreme vibration tell the AC units from that engine to shut
| down (which they already do if the rpm drops, indicating an
| engine failure-just not soon enough or reliable enough to
| prevent the smoke issue) - not so much.
|
| The system for the ECU to detect the engine mount failure
| condition already exists. The function to shut down the air
| handlers in response to a different indicator of engine failure
| already exists in the ECU. It's just literally "also shut down
| if the engine mounts fail", but the guys that sit around and
| think about the what ifs were given early retirement to make
| room for more MBAs.
| hypothesis wrote:
| > It doesn't save the engine, it keeps it from ripping the
| wing off. It's a good system.
|
| Sure, I get that it was added to prevent plane from
| disintegrating, but like you said _integration_ thinking is
| gone and now we have those individual components that sure
| look homicidal from outside.
|
| The other issue is that regulators are missing in action or
| worse. It's no way to run the industry by relying on
| concerned youtubers..
| K0balt wrote:
| I'm with you on all of this. It's like all of the grownups
| left the building and the inmates are running the asylum.
|
| Frikken clown world hijinks.
| MobiusHorizons wrote:
| I found this to be a fascinating dive into a potentially serious
| safety concern. I was impressed how simple the mitigations could
| be based on the recommendations in the report. I find the
| evidence credible for an attempt to burry the issue, but honestly
| I don't understand the motivation. At this stage I feel Boeing
| and the FAA could really stand to gain some good press from being
| extra proactive about such issues. Especially when the proposed
| mitigations seem like they would be relatively easy to implement,
| and should not be expensive for airlines from what I can see. It
| seems like the source being the engine manufacturer and
| consequently having the potential of affecting other jets
| including potentially the airbus A320 would only improve the
| incentives for Boeing to get out ahead of this, and demonstrate a
| safety culture. Does anyone understand the motivations that could
| lead to the response we have seen from the FAA and Boeing?
| xeonmc wrote:
| Could this also have been activated in the Jeju air crash from
| the initial bird strike?
| unsnap_biceps wrote:
| According to wikipedia,
| https://en.wikipedia.org/wiki/Jeju_Air_Flight_2216#Aircraft ,
| Jeju was running different engines then listed in the video as
| impacted.
| alistairSH wrote:
| IIRC, that was a 737-800 not a 737 MAX 8.
| berkut wrote:
| No, that aircraft was a 737-800 (NG), whereas the LRD is only
| on the LEAP engines of the 737 MAX...
| exabrial wrote:
| What blows my mind about anymore there are just as many AirBus
| incidents, but they aren't amplified across the internet
| echochamber. Example: https://www.youtube.com/watch?v=fgw7mG2Ivoc
|
| I'm beginning to wonder if the whole Anti Boeing sentiment was
| Russian in origin to depress their stock price for manufacturing
| weapons used in Ukraine. Absolutely zero evidence here, but I
| can't comprehend how other aviation incidents go vastly under
| reported.
| nottorp wrote:
| No, it's because they blamed an undocumented system that killed
| two plane loads of people on pilot error...
|
| Also because later they were caught forgetting to screw down
| things... see that lost door.
|
| There's about zero trust in Boeing.
| wobfan wrote:
| > No, it's because they blamed an undocumented system that
| killed two plane loads of people on pilot error...
|
| And kept hiding and sabotaging the court process against them
| to hide that they and their pilots knew, even before the
| first crash, that this might happen. Like, I don't think
| Russia or anyone else did even have to do anything at all
| here, if they would've had any reason to. Boeing fucked up
| themselves.
| greggsy wrote:
| Boeing has been in the media for a variety of corporate
| misconduct reasons, and the court cases were held in the US,
| which attracts the attention of the American media, which is a
| self-amplifying echo chamber which global consequences.
|
| I don't doubt there were similar Airbus cases, but to suggest
| that the redirected attention is wholly due to an interference
| campaign is a bit far fetched in my opinion.
| sho_hn wrote:
| These are the most comparable times in the history of Airbus:
|
| https://admiralcloudberg.medium.com/one-hundred-seconds-
| of-c...
|
| https://admiralcloudberg.medium.com/thinking-like-a-
| computer...
|
| Unlike with Boeing they didn't feature intentional
| obfuscation and fraud, but very similar themes of the
| airplane's software model of what's going on diverging from
| the pilots' and resulting in disaster.
|
| Along with stories like the Therac-25, this is one of my
| "favorite" engineering stories relevant to my profession.
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(page generated 2025-02-11 23:00 UTC)