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Smoke in the cabin of two 737 MAX caused by Load Reduction Device system [video]

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Re: Smoke in the cabin of two 737 MAX caused by Load Reduction Device system [video]

#41

Post by AdamJacobMuller »

MBCook wrote: post #40
V99 wrote: post #33

Earlier quoted context omitted.

Yes the FAA can issue what are called Airworthiness Directives and require an issue be resolved in the timeframe and manner they specify. The timeframe could be anything, but common forms are like: - Within the next X (flight) hours or Y calendar days - You don't have to, but additional inspection needed every X hours or Y days until you do - At next annual inspection - Immediate/before flying again (usually called a…

I know the FAA can, I was referring to the manufacture. If Boeing makes a software patch do they have any way of forcing everyone to install it other than asking the FAA to issue a directive?

They might be able to, but, if they are effectively saying "our product is broken and you can't use it until you do X" they could be responsible for massive contractual liabilities.

Re: Smoke in the cabin of two 737 MAX caused by Load Reduction Device system [video]

#42

Post by chipsa »

adgjlsfhk1 wrote: post #36
hypothesis wrote: post #9

Earlier quoted context omitted.

> 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.…

I think a lot of the problem here is that all of the forward looking design is looking at the 787 dreamliner where the air conditioning is done electrically rather than with bleed air. It seems entirely plausible to me that this situation arose due to a descoping halfway through the project, where an initial version of the design wasn't going to use bleed air, they then decided that doing that much design work would…

The air handling is exactly the same between the various 737 versions. The difference is that the engines are different. The CFM Leap is designed to shear the bolts on the fan if it goes sufficiently unbalanced, and incidentally the shock of this causes an oil leak. The A320neo will have a very similar problem of filling the plane with smoke if the LRD shears the fan bolts. It just does the air handling slightly differently, so it fills with smoke slower, and the entire cabin, rather than the flight deck first (if it’s the left engine that fails).

Re: Smoke in the cabin of two 737 MAX caused by Load Reduction Device system [video]

#43

Post by aunty_helen »

adgjlsfhk1 wrote: post #36
hypothesis wrote: post #9

Earlier quoted context omitted.

> 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.…

I think a lot of the problem here is that all of the forward looking design is looking at the 787 dreamliner where the air conditioning is done electrically rather than with bleed air. It seems entirely plausible to me that this situation arose due to a descoping halfway through the project, where an initial version of the design wasn't going to use bleed air, they then decided that doing that much design work would…

Nah bleed air is a pretty major system. 787 was a ground up design, so benefitted from lots of new tech. 737 max was something that they hoped wouldnt need a recert.

So no this wasn’t the victim of a rescope.

Re: Smoke in the cabin of two 737 MAX caused by Load Reduction Device system [video]

#44

Post by MichaelZuo »

AdamJacobMuller wrote: post #41
MBCook wrote: post #40

Earlier quoted context omitted.

I know the FAA can, I was referring to the manufacture. If Boeing makes a software patch do they have any way of forcing everyone to install it other than asking the FAA to issue a directive?

They might be able to, but, if they are effectively saying "our product is broken and you can't use it until you do X" they could be responsible for massive contractual liabilities.

Based on what legal reasoning…?

I haven’t heard of any similar successful court cases in recent years in the US.

Re: Smoke in the cabin of two 737 MAX caused by Load Reduction Device system [video]

#45

Post by dehrmann »

tl;dw: when a particular engine design used by the 737 MAX (but also other Boeing and Airbus planes) ingests a bird, if there's enough damage, it starts burning oil before the cabin bleed air intake. The cockpit and cabin have air supplied from different engines. Since the cockpit is relatively small, if the cockpit engine was damaged, smoke would fill the cockpit quickly, reducing the pilots' visibility and requiring them to don air masks. Bird strikes only happen at takeoff and landing--times when pilots don't have time to be fiddling with masks and seeing through smoke and trying to shut off the damaged engine. Regulators in the US and EU don't seem especially concerned.

Re: Smoke in the cabin of two 737 MAX caused by Load Reduction Device system [video]

#46

Post by sureIy »

cjbprime wrote: post #39
lukevp wrote: post #38

Earlier quoted context omitted.

Yeah but there’s 2 people in there, and 180 people in the rest of the plane. Isn’t the volume of air relative to the amount of people breathing it relevant as well?

Why do you think it would be? If 200 humans share enough air to dilute the relative concentration of poison in that air effectively, none of those humans will receive lethal doses of poison.

Only if the concentration reduces over time and the oil isn't enough to poison everyone in 69 seconds anyway.

The people can keep filtering a certain volume of oiled air, but at some point it's too much oil in their body.

Re: Smoke in the cabin of two 737 MAX caused by Load Reduction Device system [video]

#47

Post by p_l »

MichaelZuo wrote: post #44
AdamJacobMuller wrote: post #41

Earlier quoted context omitted.

They might be able to, but, if they are effectively saying "our product is broken and you can't use it until you do X" they could be responsible for massive contractual liabilities.

Based on what legal reasoning…? I haven’t heard of any similar successful court cases in recent years in the US.

Based on aviation law they can notify the certification authority of a mandatory fix which will be then required to be applied for users to aircraft operators to apply. If necessary with 0 deadline, i.e. "if the plane is on the ground it's not flying till the following change is applied"

Re: Smoke in the cabin of two 737 MAX caused by Load Reduction Device system [video]

#48

Post by aqueueaqueue »

K0balt wrote: post #10
hypothesis wrote: post #9

Earlier quoted context omitted.

> 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.…

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.

I am with you but that is quite a mixed up metaphor!

Re: Smoke in the cabin of two 737 MAX caused by Load Reduction Device system [video]

#49

Post by ngcc_hk »

chipsa wrote: post #42
adgjlsfhk1 wrote: post #36

Earlier quoted context omitted.

I think a lot of the problem here is that all of the forward looking design is looking at the 787 dreamliner where the air conditioning is done electrically rather than with bleed air. It seems entirely plausible to me that this situation arose due to a descoping halfway through the project, where an initial version of the design wasn't going to use bleed air, they then decided that doing that much design work would…

The air handling is exactly the same between the various 737 versions. The difference is that the engines are different. The CFM Leap is designed to shear the bolts on the fan if it goes sufficiently unbalanced, and incidentally the shock of this causes an oil leak. The A320neo will have a very similar problem of filling the plane with smoke if the LRD shears the fan bolts. It just does the air handling slightly diff…

Guess if I have to choose killing the pilot last is better … I am not a pilot

Re: Smoke in the cabin of two 737 MAX caused by Load Reduction Device system [video]

#50

Post by pxeger1 »

This guy says he doesn’t understand why the issue isn’t taken more seriously, and that he’s tried to cover every possible hole in his logic. Here’s a possible reason:

None of the sources he references about the danger of the smoke itself appear to be very confident that it genuinely could kill you in 39 seconds, and they all seem to be from sites that likely have an incentive to sensationalise. Maybe he had better sources for that claim, but didn’t show them (or maybe I didn’t watch the video carefully enough), but I wasn’t convinced that it’s actually true.

But if not, It’s possible the FAA/Boeing have better data or other reasoning that makes them sure that the smoke is not that dangerous. In which case their inaction (but not necessarily their PR strategy...) seems more justifiable.

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