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A comment on Preliminary conclusion MCAS misfired in Ethiopian's 737 max crash. Parent comment

Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by mhandley on Friday March 29, 2019 @06:42AM (#19520472)
Because if you did that, you'd have to alert the pilots when the AoA sensors disagree and MCAS has been disabled. And you can't do that without training them on what that means, notably how the plane will now fly differently with what you might call "relaxed stability" at high angles of attack. And Boeing really really wanted to avoid retraining of pilots because apparently they had a contract with SouthWest that would cost then $1M per plane if retraining was required.
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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by VBprogrammer on Friday March 29, 2019 @07:26AM (#19520667)
It's worth noting that there are other more engineering reasons it could be tricky to use both. An aircraft in a side slip will show different reading on the left and right sensors. Also, there are failures which are likely to impact both at much the same time, icing being a big one.
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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by mhandley on Friday March 29, 2019 @07:33AM (#19520697)
Agreed. Boeing's revised MCAS will disable itself if the AoA sensors disagree by more than 5.5 degrees when MCAS activates, or a sustained difference of more than 10 degrees otherwise. This is to take into account the fact that the sensors disagree to some degree in normal circumstances. These are fairly relaxed limits, but does demonstrate that a reasonable solution is possible.
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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by snarf21 on Friday March 29, 2019 @09:00AM (#19521199)
Right, they wanted to keep the type rating but it clear flies differently and now we have two crashes and hundreds dead.
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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by isolli on Friday March 29, 2019 @06:50AM (#19520511)
Related question: how does regulatory approval of planes work, worldwide? I read a few times that the FAA had approved the new plane too quickly, but don't other regulators have their word?
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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by Svip on Friday March 29, 2019 @07:11AM (#19520599)
FAA have (or had) such a good record, that other regulators, like EASA, simply trusted a FAA certification. In the same way, FAA trusts an EASA certification for an Airbus plane.
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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by peeters on Friday March 29, 2019 @10:50AM (#19522164)
Bilateral certification agreements. Canada and U.S. have one as well (it goes both ways): https://www.tc.gc.ca/eng/civilaviation/standards/int-baa-usa.... It's good in theory (cutting down on a giant amount of repeat work), as long as both certifying bodies maintain their standards and don't get politicized.
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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by SilasX on Friday March 29, 2019 @11:04AM (#19522305)
Well, they're working hard to change that, I guess...
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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by ricardobeat on Friday March 29, 2019 @07:21AM (#19520638)
Not only that, but apparently they also delegated most of the certification duties to Boeing itself.
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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by theelous3 on Friday March 29, 2019 @10:22PM (#19527217)
Buy toilet duck.
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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by gok on Friday March 29, 2019 @09:05AM (#19521240)
But don't Southwest planes already have the AoA disagree light, which they bought as an option?
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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by mhandley on Friday March 29, 2019 @09:09AM (#19521273)
Yes. But the AoA disagree indicator did not disable MCAS. In similar circumstances, SouthWest pilots would not have taken off, because AoA disagree would have indicated as soon as they'd begun their takeoff roll. But if an AoA sensor had failed in flight, it would still have been up to the pilots to manually disable stabilizer trim.
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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by yg6ht5 on Friday March 29, 2019 @08:25AM (#19520992)
$1M sounds like pocket change after all that has happened.
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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by bredren on Friday March 29, 2019 @08:34AM (#19521045)
Market cap loss since crash of flight 303 is $27 billion. https://ycharts.com/companies/BA/market_cap
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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by dingaling on Friday March 29, 2019 @01:21PM (#19523656)
None of which matters to Boeing as an entity. Market cap is not liquidity.

Outstanding Max order backlog is $600 billion at list price. That is what matters.

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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by ddalex on Sunday March 31, 2019 @05:03AM (#19534578)
> None of which matters to Boeing as an entity. Market cap is not liquidity.

> Outstanding Max order backlog is $600 billion at list price. That is what matters.

So at 600 billion in orders they got greedy and didn't want to spend 1M extra per plane to make it safe.

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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by acqq on Friday March 29, 2019 @08:56AM (#19521176)
Which is still nothing compared to the increase in Boeing’s market cap since some three years ago.
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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by 2sk21 on Friday March 29, 2019 @08:33AM (#19521036)
Really! This looks like a case of local optimization.
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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by marijnz on Friday March 29, 2019 @08:38AM (#19521070)
Exactly, -after-.
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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by ams6110 on Friday March 29, 2019 @09:35AM (#19521518)
Well, that's per plane. And Southwest has ordered hundreds of them.
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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by saiya-jin on Friday March 29, 2019 @09:09AM (#19521274)
If those victims would be primarily from western country, especially US, there would be almost immediate class action lawsuit against Boeing from families (US citizens seem more trigger-happy to fire lawsuits when feeling wronged, at least from my perspective).

But I guess Ethiopian/Indonesian cries for some sort of compensation/justice would have to go very viral in western media to force a corporation like Boeing into anything (since it is also a clear admission its purely their fault, which it seems to be).

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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by bunderbunder on Friday March 29, 2019 @09:39AM (#19521553)
Most countries don't have such a thing as class action, and even among the countries that have it, it's only commonly used in the one that invented the idea, and multi-national class action isn't really a thing. So I think you'd find that, far from "especially in the US," you should only expect a class action lawsuit like that for a flight that is either to or from (or both) a US airport.

With lots of of passengers on both flights being from lots of different countries, what they're getting instead is lots and lots and lots of individual lawsuits all being filed in different jurisdictions.

Which is, I'm guessing, likely to be more damaging to them in the long run.

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Re:Preliminary conclusion MCAS misfired in Ethiopian's 737 m... by wp381640 on Friday March 29, 2019 @10:41AM (#19522071)
First Ethiopia lawsuit was filed today in Chicago

MH370 was a multi-national class-action lawsuit filed in SC that was only dismissed because the circumstances of the disappearance were not clear and nothing to do with it being multi-national

https://www.documentcloud.org/documents/3512628-16319045179....

With the Lion Air crash the settlements the Indonesian government had passengers sign included waiving any right to sue Boeing in the USA

https://www.nytimes.com/2019/03/21/world/asia/lion-air-crash...

The fault being with Boeing in this case seems a lot more clear-cut

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