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Ethiopian Airlines Boeing 737 pilots 'could not stop nosedive'

203 points by jfk13 8y ago

aschwabe 8y ago
Has anyone checked if there is MCAS on the 787?
- raverbashing 8y ago
  No there isn't
  - dingaling 8y ago
    But there is on the KC-46 tanker for the USAF, but unlike the MAX it cuts-out upon pilot control input: http://www.airforcemag.com/Features/Pages/2019/March%202019/USAF-Reviewing-Training-After-MAX-8-Crashes-KC-46-Uses-Similar-MCAS-System.aspx http://www.airforcemag.com/Features/Pages/2019/March%202019/... Again it derives from trying to push an older non-FBW design to new limits; a 767 wasn't designed for the large shifts in CoG which occur when offloading fuel in flight. A FBW type like the A330 that was its rival for the USAF contract can just subtly command constant minir trim changes.
    - raverbashing 8y ago
      Interesting, I didn't know this. Maybe the KC-46 was the prototype (though it might be checking other inputs) to the MAX system? > The KC-46 has a two-sensor MCAS system, which “compares the two readings,” the Air Force said. > Moreover, while the MAX 8 MCAS will reset and come back on automatically, the KC-46’s system is “disengaged if the pilot makes a stick input,” according to the Air Force So it seems someone did their homework in this case (well hadn't they done, it would have gotten very ugly as well)
guylepage3 8y ago
I’m a social capitalist. IMO, it seldom happens that the free market does not punish companies who make serious errors. For those times, logic, common sense & societal regulation should step in, punish the company with fines ratcheting up until free market clearly loses confidence.
- golergka 8y ago
  With this kind of publicity I don't see how can Boeing can possibly not punished by the market itself. Even before 737 Max fleet was grounded, I already started hearing, from a lot of different people, that they wouldn't fly on that plane.
  - Dirlewanger 8y ago
    Can one even accurately know what plane they will be on until mere hours before? Does flightradar help with this?
- DigiMortal 8y ago
  The biggest issue with these massive commercial aerospace companies is a huge barrier to entry, like I can only think of Boeing and Airbus that are really legit in this space. What these companies do/build are insanely difficult, require decades of expertise, infrastructure, so much goes into...are these institutions or companies lol
toxictroller 8y ago
Perhaps the pilots didn't have the energy to pull up due to the famine?
- henrygrew 8y ago
  You don't belong in this community
  - Spare_account 8y ago
    As per HN comment guidelines, it's best not to reply to comments like this and just flag them. The admins are usually quick to respond. https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html > Don't feed egregious comments by replying; flag them instead.
    - matt4077 8y ago
      FWIW in this case I appreciate the rather appropriate reply. If such comments simply disappear, it sometimes feels like all that protects HN are the two or three Moderators doing their duty. I feel more reassured by knowing the wider community will not tolerate such behavior. And it also sends a stronger message, one where these people can not delude themselves into thinking they are representative of us, and/or “speaking truth to power”.
  - hombre_fatal 8y ago
    Better for a troll to see their post casually ignored than to receive exactly what they want.
    - markmm 8y ago
      True, replying just gives the attention they seek
rocqua 8y ago
If this was indeed MCAS, it is my understanding they 'could have' stopped this by turning off power to the electronic stabilizer trim.
- jpatokal 8y ago
  Per the friendly article, "Pilots "repeatedly" followed procedures recommended by Boeing before the crash, according to the first official report into the disaster."
  - lorenzobr 8y ago
    Exactly. I find it embarrassing for the society as whole how many people these days comment on articles or posts by just reading the title.
    - rocqua 8y ago
      I read the article, hence my reaction. Because to me, the claims of the article do not match my understanding of the procedures defined for dealing with a failing MCAS.
  - treis 8y ago
    I'm interested to see what the report says about this. My understanding is that the procedure is "turn off electric trim and don't turn it back on". Not a procedure that you can follow "repeatedly".
- plq 8y ago
  Maybe you're right, but were they trained to know about this?
- Tsubasachan 8y ago
  Ah yes ofcourse. Just hit pause to stop time, mute the people screaming in the rear, get a cup of coffee, sit back and think out of the box.
  - 8y ago
WheelsAtLarge 8y ago
This is a software screwup. It's buggy software due to rush to market. I hope they do an analysis of the whole project. We can all learn from it.
- GrumpyNl 8y ago
  At the cost of 300 lives.
- bobcostas55 8y ago
  The software did what it was supposed to, the issue was the specification necessitated by the design change.
  - sundvor 8y ago
    Yep, the issues started way earlier than the software. In fact the software is at the very end of the chain here, unless you also want to insert "no training". It all started when they wanted those big engines crammed into an airframe not designed to hold them, so as to try to quickly catch up to shifting market demands being met by Airbus.
    - cdolan 8y ago
      How can you say “no training” caused this second crash after reading the article? Did you read the article?
      - Tor3 8y ago
        (Edited) They had training (and sundvor didn't say otherwise), but still, remember Boeing's decision that little or no re-training for the Max was needed for pilots already having 737 training. See e.g. https://edition.cnn.com/2019/03/22/politics/boeing-737-manual/index.html https://edition.cnn.com/2019/03/22/politics/boeing-737-manua...
        sundvor 8y ago
mhandley 8y ago
Will be interesting to see the details when the report is actually public. It does sound like the scenario that Mentourpilot explored in the simulator is close to what happened, namely: Bad AoA probe causes MCAS to trim down, and also to indicate IAS disagree. Pilots increase throttle as per non-normal checklist to reduce the risk of stalling due to unreliable airspeed. Pilots disable electric stabilizer trim, as per Boeing's advice, without trimming back to neutral trim. Plane is now low, accelerating, and trimmed nose down. Pilots likely started to trim up with the manual trim wheels, but that's very slow, and gets harder as airspeed increases. And you don't want to reduce power, because that will cause a pitch-down, and you're close to the ground. At this point you've run out of options that are recommended by Boeing. The only remaining option is to re-enable electric stabilizer trim, and use that to trim nose-up. Now, from what I understand, appying nose-up electric trim should override MCAS, and so this course of action should be possible. However, at this point, you're basically a test pilot - this is not on any of Boeing's checklists or training. Why didn't it work? We'll have to wait for the full report for that I think.
- lysp 8y ago
  Does anyone have a mirror of that video?
  - mhandley 8y ago
    This was posted on PPrune: "Originally Posted by infrequentflyer789 Since this video may not be coming back I'll post a sort of transcript from memory since I was lucky enough to get to watch it. I'll try and just describe what I saw and keep my commentary/speculation to a minimum - in <italic>. Bear in mind this is a non-pilot observer's take on it from flaky memory: There is a fair bit of intro talk then the sim. They are in NG sim, not MAX, no surprise there. Mentour in left seat. They start at low altitude, I think it was commented on, not at takeoff, I can't remember if they showed putting flaps up or started with flaps up and said it was just after flaps up. No stick shaker, that I saw. <presume means no elevator feel shift either, and that actual AOA error is not being simulated> IAS disagree then simulated - or they just did the memory items, I didn't notice warning light (not that I would) and he didn't note it, there was an aural alarm but I think that was for AP disconnect <I don't think this is exactly what the accident flights faced, they had shaker and IAS disagree from takeoff> IAS disagree memory items, AP/AT OFF, FDs OFF, 75% N1, 4degrees Throttles are pushed forward to get 75%, he comments that at low alt with denser air this is a lot of thrust and hence speed will increase Trim runs, obviously sim doesn't have MCAS so not sure if they are simulating runaway or if he is doing it with the column switches Comment is made that he was _expecting_ trim to run, because speed is changing, he says it will take a couple of cycles of fighting it with the switches before being definite that it is wrong They discuss (he raises) that he is having flight control issue, they conclude it is trim that is the problem, they now run the stab trim runaway memory items finishing by hitting the switches. At this point he is clearly holding quite a bit of pressure on the column, but not obviously losing control of pitch Now he points out that trim has only got down to (I think) 3 degrees on the indicator (zero being full nose down, I think) and that they are now going to "try something" - video captions say "don't try this at home", like we've all got a FFS in our shed or a 737 on the drive :-) At this point the guy in the right seat uses the handle to wind the trim further _forward_. He stops when he clearly cannot wind it further - but they point out that it's still not at full nose down Mentour is obviously struggling to keep the nose up at this point. I noticed he didn't seem to have the shoulder straps on (right seat did), possibly because he was frequently turning round to talk to the camera. That probably didn't help, but on the other hand he didn't have stick shaker or feel shift to cope with either. Now, with Mentour pulling back, the right seat guy tries to wind the trim back with the handle - and he struggles to move it at all They stop the sim, I think it was after stopping that he noted that at that point they were at 310 (maybe he said 340) knots. I think there was then some further commentary, at one point I think he mentioned the rollercoaster to unload the stab and allow trimming, but commented that close to the ground the instinct is to pull back - I may be imagining that or remembering it from another video though. And that was about it. I can try to answer questions on the video if anyone has any. The eye-opener for me wasn't the force on the control column (which was held anyway), it was that the trim couldn't be moved, in either direction. From somewhere I had got the impression that those wheels had a lot of leverage, due to the gearing, which was why a lot of turns would be required, but it seems that a lot of turns would be required and a gorilla to make them..."
raverbashing 8y ago
Funny how people were saying that it was just a matter of pilots shutting off the system... Looks like 1) Ethiopian pilots were up to date in training (good for them) 2) MCAS should have never been shipped
deepstream 8y ago
pilots should not have to fight the system. can there not be a simple button, "switch to manual"?
- matt4077 8y ago
  Airline safety has increased by a factor of 100 in the last 50 years, in terms of fatalities / miles travelled. Both in the past and now, far more accidents are the result of pilot error than failure of any system. Gloryfing the good old days of pilot jocks just isn’t supported by the actual data, this incident nonewithstanding.
  - xmeyers 8y ago
    Isn't that orthogonal to the previous statement? The ideal situation would be to have fly-by-wire and a single hands-off button instead of HAL saying "Sorry Dave, but I cannot do that". Of course, commercial pilots would need to have an actual interest in flying manually. The Gimli glider pilot was an enthusiastic pilot outside professional aviation. I don't know if such an interest is still possible with modern exploitative labor practices.
    - femto113 8y ago
      I’d go beyond an “off switch” and argue that any software that’s smart enough to turn itself on without being asked needs to turn itself off if it’s obvious that the pilot is fighting against it. It’s like a classic Bayesian probability problem where the chance of a false positive is high. The software has to take into account that the stall scenario it thinks is happening is rare, and that happening followed by a pilot yanking back on the stick is vanishingly rare, accept that it was probably wrong and undo its actions.
  - deepstream 8y ago
    at least you're not in charge of anything. the plane's crashing, and you're telling the pilots (who you think might be jocks which makes you feel...even less safe?), "No don't turn it off, I have 50 years of data that says systems are safe." perfect example of doing data wrong. crazy dangerous arrogant ideas like this contributed to this tragedy. when the systems are failing, you better hope you have some pilot jocks / true fixed wing enthusiasts at the controls, who know how to make the systems work for them, or take control if they fail, rather than some data jocks, with blinkered faith in the systems, who count cost of lives as "notwithstanding". flyers deserve competence from their systems and data, not just from their pilots. we need pilots who have earned their capabilities, and systems that have earned their impression of reliability. current MCAS occupies a privileged position in charge of safety it has not earned.
matt4077 8y ago
I’d love to see those people who accused the airline and crew of being incompetent to apologize in the light of these reports. It was shameful to see Boeing actively encouraging that narrative behind the scenes. Especially considering it plays on racist stereotypes equating „Africa“ with bad training/bad safety record/…. The idea of „dingy third world airline“ was ridiculous on its face, considering how bad a fit flying the most modern airliner is with it. And it was also contradicted by the factual record of Ethopian being a competent airline on par with any in Europe or North America. Their safety rating is better than easyjet, Ryanair, Spirit, WOW, and Southwest: https://www.airlineratings.com/safety-rating-tool/ https://www.airlineratings.com/safety-rating-tool/
- watwat1 8y ago
  You’re right. Africa is clearly a haven of technological innovation and progress.
- drsim 8y ago
  While I agree with your sentiment on stereotypes, looking at the link your comment seems misleading. The airlines you mention score lower on 'Safety Rating' due to lack of IOSA certification. "Registering for IOSA certification and auditing is not mandatory therefore an airline that does not have IOSA certification may have either failed the IOSA audit or alternatively chosen not to participate." For a budget airline I can see them not participating for cost reasons. Does this make them less safe?
  - matt4077 8y ago
    Safety incidents in air travel are thankfully low. Therefore, it is impossible to find meaningful differences in that primary data alone. You have to find some proxies, and certification schemes seem at least defensible in that regard. In any case, not being a „budget“ airline that has to cut such costs would seem to fit rather well with my argument that Ethopian is not some gravel-airstrip bush operation flying leftover Sowiet machinery.
    - 8y ago
DanielBMarkham 8y ago
There you have it, folks, programmers killing people. No, it wasn't on-purpose, but that doesn't mean it didn't happen. This, of course, has been happening for a long time, it's just getting more and more obvious now. I feel strongly that AF 447 was an example. It's important to understand that this is the natural result of two trends. One, software/hardware systems continue to become more and more complex, many times leading to unforeseen interactions. Two, programmers and programming management teams love to bunch up the work by things not related to the end-users: hardware component, new modules, architectural tier, underlying technology involved. It doesn't take very much of that at all before you have a whole bunch of people all doing work of various quality in small enough isolated silos such that everybody can do a wonderful job -- and the system still kill people. There's a lot more to add here. It's nothing new, and there are a ton of ways we've tried to fix this. My belief is that we've failed because we don't understand exactly what goes into making successful software at scale. I am quite concerned about it and I have been writing on this topic for several years. If you're interested in more, see my profile.
- carbocation 8y ago
  Why is this a software problem? Even if there is a software “fix,” doesn’t it seem that this tells us more about regulatory capture than using software to patch over bad hardware decisions?
  - carlmr 8y ago
    It's a bad mechanical design, Boeing didn't want to spend money on retraining pilots, they asked software to fix it, software fixed it so that it remained the same, software had a bug, training didn't incorporate new system, because that was the point of the software, to not require a new type rating. I think this is process failure from start to finish. Any sufficiently complex system will have bugs in it, whether it's software or not. I think the other failures are much worse. You have to account for your system maybe failing and your pilots have to be trained to deal with this failure. And yes, software kills people, but no software kills even more people. Just look at how airplanes, cars etc. have improved safety through assistance systems.
vfinn 8y ago
Every time I read about these plane accidents, I wonder why planes don't have any emergency features to save these people. Couldn't you build a plane that would eject the cabin as a parachute module or something. Yes, I'm sure this is naive, but why? Edit: My point is that almost anything is better than crashing down with the plane.
- jfk13 8y ago
  Can you imagine the scale of parachute that would be needed to safely bring an airliner cabin to earth? Could a parachute on that scale actually be made sufficiently strong (and light), and successfully deployed? I doubt it.
  - ajuc 8y ago
    Yes. It would be expansive though.
  - agumonkey 8y ago
    I want a wingsuit on my ticket. If I die at least I'll be superman-like for 30minutes
  - saiya-jin 8y ago
    Imagine 500m wide parachute. Would probably weight few tonnes, be very complex to deploy (say only above 1-2km altitude), very hard to inspect regularly etc. The other problem is, a lot of death/damage is done after plane hits the ground and starts to burn. You wouldn't be able to prevent that, since emergency parachute falls are hard ones. So you might still end up killing everybody on plane.
- agumonkey 8y ago
  costs and motivation I suppose some air vehicles have whole frame parachutes but not the scale of 737. I was wondering if a plane could not be made out of separate cabins coupled together (I can hear engineers die of laughter) so that they could be break loose with their own parachute.
  - 8y ago
prmph 8y ago
Maybe this is a naive question, but why can't the automated controls on plane be designed such that: 1. They can be independently disabled? 2. For MCAS in particular, disabling it will automatically revert to the previous trim level before it shuts off? 3. They can rely on sensors that are kept in enclosed storage (thus much less likely to fail due to freezing, etc) and immediately deployed when there is a problem with the usual sensors? Like the RAM air turbine? Most auto-pilot malfunctions seem to be due to sensors going bad. Edit: Sorry I wasn't clearer the first time, but I meant the enclosed redundant sensors would be brought outside when needed, and retracted when not in use. Even the pitot tube could benefit from such a scheme
- Neil44 8y ago
  I guess it would be the complexity of the troubleshooting procedures involved if every feature had it's own disabler. You only have a short time under high pressure to resolve these issues so I can see that fewer, broader stroke options would be better.
- crocal 8y ago
  Implementor of similar systems here. 1. It's possible, but you have to understand that a pilot, however bright he may be, cannot be overloaded with too many modes of operations. You can't always have Neil Armstrong driving... 2. We have to wait for the conclusions of the investigation. There is obviously still a lot of question marks about what /should/ occur and what /did/ occur, so it's difficult to speculate (at least for me) on what a correct implementation of the system should have been. 3. Each sensor has pros and cons. For an AOA, I am not an expert, but well, it's supposed to measure the lift under the wing, so I don't see how you can avoid being outdoor to get a direct measure of this quantity. I believe someone on HN more expert could give more insight here, but my experience when you try to use indirect sensors is that it générâtes the need for /more/ computational complexity to deduce the intended measure from indirect sources. For your last comment, I would complement that auto pilots malfunction due to sensors going bad /unnoticed/. We should take "going bad" very broadly: either the sensor is broken, or it is not picking up something that it should because, well, the designer just did not think about it.
aaron695 8y ago
Currently we are quoting an Ethiopian Transport Minister. We should be worried that they are setting the narrative before the report is released. What people hear now will override what the report actually says tomorrow, a normal tactic of politicians. And even if you think capitalism means the airline will be world standard, at 114/179 on the corruption index I'd not trust their politicians. We get to check when the report comes out I guess.
deleted 8y ago
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- deleted 8y ago
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dis-sys 8y ago
With such new evidence, how FAA which refused to ground the 737 Max should be allowed to walk away from all these for nothing?
- jki275 8y ago
  The FAA did ground the 737 Max.
  - dis-sys 8y ago
    FAA defended 737 Max to the very last minute, FAA is nothing else but a cheap tool for big corporations like Boeing.
    - jki275 8y ago
      The last minute when they grounded them? I don't recall them "defending" anything, anyway, they simply held off grounding them until they got a little bit of data to back it up.
      - dis-sys 8y ago
        > they simply held off grounding them until they got a little bit of data to back it up In my dictionary I have the following term which FAA and Boeing both actively ignored/violated. pre·cau·tion /prəˈkôSH(ə)n/ noun a measure taken in advance to prevent something dangerous, unpleasant, or inconvenient from happening.
        jki275 8y ago
        You have to balance "precaution" with "knee-jerk".
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antocv 8y ago
Change the title please, now it reads as if the Ethiopian Airlines were at fault for "not stopping nosedive" Title should be "Boeing 737 nose-dived and crashed due to capitalism, killing Ethiopians".
- SmellyGeekBoy 8y ago
  The reason they were flying in the first place was due to capitalism. The reason you're able to read this story on this website is due to capitalism. I don't get your point.
- matt4077 8y ago
  Somehow your opinion of capitalism is on par with your idea that only Ethiopians fly on Ethopian Airlines.
markmm 8y ago
If this was a bug it would have presented in other airliners as software is an exact copy. Sound's like human or hardware fault.
rutthenut 8y ago
Some other info aggregated here https://www.theverge.com/2019/4/4/18294317/boeing-737-max-ethiopian-airlines-crash-report https://www.theverge.com/2019/4/4/18294317/boeing-737-max-et... Clear to most that the software has/had an appalling design for error-handling, with tragic results, and blame from Boeing to deflect that
draw_down 8y ago
After the second crash of this plane model within 6 months, the call to ground the 737 Max until we understand why the crashes happened was labeled an overreaction. As if safety should not be the first priority, as if abundance of caution is a bad thing. It was very interesting to watch this happen; I thought, why wouldn’t you want to be cautious? My take on it is there’s a “boy who cried wolf” effect where everything gets branded as over-the-top, unnecessary outrage, etc, that our judgement has been affected. Our ability to recognize and respond to truly exceptional circumstances is diminished. It’s so easy now to paint people as being hysterical or whatever, but sometimes cool calm and collected is actually not the correct stance.
hckr123 8y ago
Old news https://www.bloomberg.com/news/articles/2018-03-08/american-airlines-to-retire-45-boeing-737s-over-next-two-years https://www.bloomberg.com/news/articles/2018-03-08/american-... Just retire the whole plane
segmondy 8y ago
I thought this was a software failure initially, but upon following the case, I have come to realize it's not. I still see plenty of people saying this is a software failure in this thread. This is not a software failure. This is a system/process failure on many level. The plane was rushed to beat a competitor. A mismatch between the plane & engine happened which can cause it to be off balance. A system was added in place to correct it, but this system only used one sensor instead of 2. The display could have displayed angle of attack which is a safety gauge, but it's optional and was charged for. $80k on a $120 million plane. It's now standard. The display could also display a disagree light if the 2 sensors disagree, but that is also an optional feature, which will now be made standard. The MCSA was only suppose to adjust for .5 degrees and when Boeing & FAA worked together, this was the agreed parameter, but Boeing changed it after the fact to I believe 2.5 and never informed the FAA. FAA only discovered this after the Lion crash. This new system was not documented. It was not in the flight manual or training. Boeing lied to pilots when they asked if there's any new system they should know about. FAA wasn't through in certification process and allowed Boeing to sign off some things themselves. The failure was on so many levels it's ridiculous. It's a whole collapse of a system. Boeing, FAA, certification, QA, hardware design, etc. If anything I won't even blame the software team much, software has no choice but to rely on the signal it's reading from the sensor if invalid. My concern is that the plane wasn't tested with faulty sensor. A happy path was followed. Testing with faulty sensor data might have shown the tug of war that would have happened between the pilot & plane. All in all, failure is across so many levels, it's terrible.
- salawat 8y ago
  This has been just about my exact conclusion. I've just been checking things off as the evidence rolls in.

203 points by jfk13 8y ago

aschwabe 8y ago

Has anyone checked if there is MCAS on the 787?

raverbashing 8y ago
No there isn't
- dingaling 8y ago
  But there is on the KC-46 tanker for the USAF, but unlike the MAX it cuts-out upon pilot control input: http://www.airforcemag.com/Features/Pages/2019/March%202019/USAF-Reviewing-Training-After-MAX-8-Crashes-KC-46-Uses-Similar-MCAS-System.aspx http://www.airforcemag.com/Features/Pages/2019/March%202019/... Again it derives from trying to push an older non-FBW design to new limits; a 767 wasn't designed for the large shifts in CoG which occur when offloading fuel in flight. A FBW type like the A330 that was its rival for the USAF contract can just subtly command constant minir trim changes.
  - raverbashing 8y ago
    Interesting, I didn't know this. Maybe the KC-46 was the prototype (though it might be checking other inputs) to the MAX system? > The KC-46 has a two-sensor MCAS system, which “compares the two readings,” the Air Force said. > Moreover, while the MAX 8 MCAS will reset and come back on automatically, the KC-46’s system is “disengaged if the pilot makes a stick input,” according to the Air Force So it seems someone did their homework in this case (well hadn't they done, it would have gotten very ugly as well)

guylepage3 8y ago

I’m a social capitalist. IMO, it seldom happens that the free market does not punish companies who make serious errors. For those times, logic, common sense & societal regulation should step in, punish the company with fines ratcheting up until free market clearly loses confidence.

golergka 8y ago
With this kind of publicity I don't see how can Boeing can possibly not punished by the market itself. Even before 737 Max fleet was grounded, I already started hearing, from a lot of different people, that they wouldn't fly on that plane.
- Dirlewanger 8y ago
  Can one even accurately know what plane they will be on until mere hours before? Does flightradar help with this?
DigiMortal 8y ago
The biggest issue with these massive commercial aerospace companies is a huge barrier to entry, like I can only think of Boeing and Airbus that are really legit in this space. What these companies do/build are insanely difficult, require decades of expertise, infrastructure, so much goes into...are these institutions or companies lol

toxictroller 8y ago

Perhaps the pilots didn't have the energy to pull up due to the famine?

henrygrew 8y ago
You don't belong in this community
- Spare_account 8y ago
  As per HN comment guidelines, it's best not to reply to comments like this and just flag them. The admins are usually quick to respond. https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html > Don't feed egregious comments by replying; flag them instead.
  - matt4077 8y ago
    FWIW in this case I appreciate the rather appropriate reply. If such comments simply disappear, it sometimes feels like all that protects HN are the two or three Moderators doing their duty. I feel more reassured by knowing the wider community will not tolerate such behavior. And it also sends a stronger message, one where these people can not delude themselves into thinking they are representative of us, and/or “speaking truth to power”.
- hombre_fatal 8y ago
  Better for a troll to see their post casually ignored than to receive exactly what they want.
  - markmm 8y ago
    True, replying just gives the attention they seek

rocqua 8y ago

If this was indeed MCAS, it is my understanding they 'could have' stopped this by turning off power to the electronic stabilizer trim.

jpatokal 8y ago
Per the friendly article, "Pilots "repeatedly" followed procedures recommended by Boeing before the crash, according to the first official report into the disaster."
- lorenzobr 8y ago
  Exactly. I find it embarrassing for the society as whole how many people these days comment on articles or posts by just reading the title.
  - rocqua 8y ago
    I read the article, hence my reaction. Because to me, the claims of the article do not match my understanding of the procedures defined for dealing with a failing MCAS.
- treis 8y ago
  I'm interested to see what the report says about this. My understanding is that the procedure is "turn off electric trim and don't turn it back on". Not a procedure that you can follow "repeatedly".
plq 8y ago
Maybe you're right, but were they trained to know about this?
Tsubasachan 8y ago
Ah yes ofcourse. Just hit pause to stop time, mute the people screaming in the rear, get a cup of coffee, sit back and think out of the box.
- 8y ago

WheelsAtLarge 8y ago

This is a software screwup. It's buggy software due to rush to market. I hope they do an analysis of the whole project. We can all learn from it.

GrumpyNl 8y ago
At the cost of 300 lives.
bobcostas55 8y ago
The software did what it was supposed to, the issue was the specification necessitated by the design change.
- sundvor 8y ago
  Yep, the issues started way earlier than the software. In fact the software is at the very end of the chain here, unless you also want to insert "no training". It all started when they wanted those big engines crammed into an airframe not designed to hold them, so as to try to quickly catch up to shifting market demands being met by Airbus.
  - cdolan 8y ago
    How can you say “no training” caused this second crash after reading the article? Did you read the article?
    - Tor3 8y ago
      (Edited) They had training (and sundvor didn't say otherwise), but still, remember Boeing's decision that little or no re-training for the Max was needed for pilots already having 737 training. See e.g. https://edition.cnn.com/2019/03/22/politics/boeing-737-manual/index.html https://edition.cnn.com/2019/03/22/politics/boeing-737-manua...
      - sundvor 8y ago

mhandley 8y ago

Will be interesting to see the details when the report is actually public. It does sound like the scenario that Mentourpilot explored in the simulator is close to what happened, namely: Bad AoA probe causes MCAS to trim down, and also to indicate IAS disagree. Pilots increase throttle as per non-normal checklist to reduce the risk of stalling due to unreliable airspeed. Pilots disable electric stabilizer trim, as per Boeing's advice, without trimming back to neutral trim. Plane is now low, accelerating, and trimmed nose down. Pilots likely started to trim up with the manual trim wheels, but that's very slow, and gets harder as airspeed increases. And you don't want to reduce power, because that will cause a pitch-down, and you're close to the ground. At this point you've run out of options that are recommended by Boeing. The only remaining option is to re-enable electric stabilizer trim, and use that to trim nose-up. Now, from what I understand, appying nose-up electric trim should override MCAS, and so this course of action should be possible. However, at this point, you're basically a test pilot - this is not on any of Boeing's checklists or training. Why didn't it work? We'll have to wait for the full report for that I think.

lysp 8y ago
Does anyone have a mirror of that video?
- mhandley 8y ago
  This was posted on PPrune: "Originally Posted by infrequentflyer789 Since this video may not be coming back I'll post a sort of transcript from memory since I was lucky enough to get to watch it. I'll try and just describe what I saw and keep my commentary/speculation to a minimum - in <italic>. Bear in mind this is a non-pilot observer's take on it from flaky memory: There is a fair bit of intro talk then the sim. They are in NG sim, not MAX, no surprise there. Mentour in left seat. They start at low altitude, I think it was commented on, not at takeoff, I can't remember if they showed putting flaps up or started with flaps up and said it was just after flaps up. No stick shaker, that I saw. <presume means no elevator feel shift either, and that actual AOA error is not being simulated> IAS disagree then simulated - or they just did the memory items, I didn't notice warning light (not that I would) and he didn't note it, there was an aural alarm but I think that was for AP disconnect <I don't think this is exactly what the accident flights faced, they had shaker and IAS disagree from takeoff> IAS disagree memory items, AP/AT OFF, FDs OFF, 75% N1, 4degrees Throttles are pushed forward to get 75%, he comments that at low alt with denser air this is a lot of thrust and hence speed will increase Trim runs, obviously sim doesn't have MCAS so not sure if they are simulating runaway or if he is doing it with the column switches Comment is made that he was _expecting_ trim to run, because speed is changing, he says it will take a couple of cycles of fighting it with the switches before being definite that it is wrong They discuss (he raises) that he is having flight control issue, they conclude it is trim that is the problem, they now run the stab trim runaway memory items finishing by hitting the switches. At this point he is clearly holding quite a bit of pressure on the column, but not obviously losing control of pitch Now he points out that trim has only got down to (I think) 3 degrees on the indicator (zero being full nose down, I think) and that they are now going to "try something" - video captions say "don't try this at home", like we've all got a FFS in our shed or a 737 on the drive :-) At this point the guy in the right seat uses the handle to wind the trim further _forward_. He stops when he clearly cannot wind it further - but they point out that it's still not at full nose down Mentour is obviously struggling to keep the nose up at this point. I noticed he didn't seem to have the shoulder straps on (right seat did), possibly because he was frequently turning round to talk to the camera. That probably didn't help, but on the other hand he didn't have stick shaker or feel shift to cope with either. Now, with Mentour pulling back, the right seat guy tries to wind the trim back with the handle - and he struggles to move it at all They stop the sim, I think it was after stopping that he noted that at that point they were at 310 (maybe he said 340) knots. I think there was then some further commentary, at one point I think he mentioned the rollercoaster to unload the stab and allow trimming, but commented that close to the ground the instinct is to pull back - I may be imagining that or remembering it from another video though. And that was about it. I can try to answer questions on the video if anyone has any. The eye-opener for me wasn't the force on the control column (which was held anyway), it was that the trim couldn't be moved, in either direction. From somewhere I had got the impression that those wheels had a lot of leverage, due to the gearing, which was why a lot of turns would be required, but it seems that a lot of turns would be required and a gorilla to make them..."

raverbashing 8y ago

Funny how people were saying that it was just a matter of pilots shutting off the system... Looks like 1) Ethiopian pilots were up to date in training (good for them) 2) MCAS should have never been shipped

deepstream 8y ago

pilots should not have to fight the system. can there not be a simple button, "switch to manual"?

matt4077 8y ago
Airline safety has increased by a factor of 100 in the last 50 years, in terms of fatalities / miles travelled. Both in the past and now, far more accidents are the result of pilot error than failure of any system. Gloryfing the good old days of pilot jocks just isn’t supported by the actual data, this incident nonewithstanding.
- xmeyers 8y ago
  Isn't that orthogonal to the previous statement? The ideal situation would be to have fly-by-wire and a single hands-off button instead of HAL saying "Sorry Dave, but I cannot do that". Of course, commercial pilots would need to have an actual interest in flying manually. The Gimli glider pilot was an enthusiastic pilot outside professional aviation. I don't know if such an interest is still possible with modern exploitative labor practices.
  - femto113 8y ago
    I’d go beyond an “off switch” and argue that any software that’s smart enough to turn itself on without being asked needs to turn itself off if it’s obvious that the pilot is fighting against it. It’s like a classic Bayesian probability problem where the chance of a false positive is high. The software has to take into account that the stall scenario it thinks is happening is rare, and that happening followed by a pilot yanking back on the stick is vanishingly rare, accept that it was probably wrong and undo its actions.
- deepstream 8y ago
  at least you're not in charge of anything. the plane's crashing, and you're telling the pilots (who you think might be jocks which makes you feel...even less safe?), "No don't turn it off, I have 50 years of data that says systems are safe." perfect example of doing data wrong. crazy dangerous arrogant ideas like this contributed to this tragedy. when the systems are failing, you better hope you have some pilot jocks / true fixed wing enthusiasts at the controls, who know how to make the systems work for them, or take control if they fail, rather than some data jocks, with blinkered faith in the systems, who count cost of lives as "notwithstanding". flyers deserve competence from their systems and data, not just from their pilots. we need pilots who have earned their capabilities, and systems that have earned their impression of reliability. current MCAS occupies a privileged position in charge of safety it has not earned.

matt4077 8y ago

I’d love to see those people who accused the airline and crew of being incompetent to apologize in the light of these reports. It was shameful to see Boeing actively encouraging that narrative behind the scenes. Especially considering it plays on racist stereotypes equating „Africa“ with bad training/bad safety record/…. The idea of „dingy third world airline“ was ridiculous on its face, considering how bad a fit flying the most modern airliner is with it. And it was also contradicted by the factual record of Ethopian being a competent airline on par with any in Europe or North America. Their safety rating is better than easyjet, Ryanair, Spirit, WOW, and Southwest: https://www.airlineratings.com/safety-rating-tool/ https://www.airlineratings.com/safety-rating-tool/

watwat1 8y ago
You’re right. Africa is clearly a haven of technological innovation and progress.
drsim 8y ago
While I agree with your sentiment on stereotypes, looking at the link your comment seems misleading. The airlines you mention score lower on 'Safety Rating' due to lack of IOSA certification. "Registering for IOSA certification and auditing is not mandatory therefore an airline that does not have IOSA certification may have either failed the IOSA audit or alternatively chosen not to participate." For a budget airline I can see them not participating for cost reasons. Does this make them less safe?
- matt4077 8y ago
  Safety incidents in air travel are thankfully low. Therefore, it is impossible to find meaningful differences in that primary data alone. You have to find some proxies, and certification schemes seem at least defensible in that regard. In any case, not being a „budget“ airline that has to cut such costs would seem to fit rather well with my argument that Ethopian is not some gravel-airstrip bush operation flying leftover Sowiet machinery.
  - 8y ago

DanielBMarkham 8y ago

There you have it, folks, programmers killing people. No, it wasn't on-purpose, but that doesn't mean it didn't happen. This, of course, has been happening for a long time, it's just getting more and more obvious now. I feel strongly that AF 447 was an example. It's important to understand that this is the natural result of two trends. One, software/hardware systems continue to become more and more complex, many times leading to unforeseen interactions. Two, programmers and programming management teams love to bunch up the work by things not related to the end-users: hardware component, new modules, architectural tier, underlying technology involved. It doesn't take very much of that at all before you have a whole bunch of people all doing work of various quality in small enough isolated silos such that everybody can do a wonderful job -- and the system still kill people. There's a lot more to add here. It's nothing new, and there are a ton of ways we've tried to fix this. My belief is that we've failed because we don't understand exactly what goes into making successful software at scale. I am quite concerned about it and I have been writing on this topic for several years. If you're interested in more, see my profile.

carbocation 8y ago
Why is this a software problem? Even if there is a software “fix,” doesn’t it seem that this tells us more about regulatory capture than using software to patch over bad hardware decisions?
- carlmr 8y ago
  It's a bad mechanical design, Boeing didn't want to spend money on retraining pilots, they asked software to fix it, software fixed it so that it remained the same, software had a bug, training didn't incorporate new system, because that was the point of the software, to not require a new type rating. I think this is process failure from start to finish. Any sufficiently complex system will have bugs in it, whether it's software or not. I think the other failures are much worse. You have to account for your system maybe failing and your pilots have to be trained to deal with this failure. And yes, software kills people, but no software kills even more people. Just look at how airplanes, cars etc. have improved safety through assistance systems.

vfinn 8y ago

Every time I read about these plane accidents, I wonder why planes don't have any emergency features to save these people. Couldn't you build a plane that would eject the cabin as a parachute module or something. Yes, I'm sure this is naive, but why? Edit: My point is that almost anything is better than crashing down with the plane.

jfk13 8y ago
Can you imagine the scale of parachute that would be needed to safely bring an airliner cabin to earth? Could a parachute on that scale actually be made sufficiently strong (and light), and successfully deployed? I doubt it.
- ajuc 8y ago
  Yes. It would be expansive though.
- agumonkey 8y ago
  I want a wingsuit on my ticket. If I die at least I'll be superman-like for 30minutes
- saiya-jin 8y ago
  Imagine 500m wide parachute. Would probably weight few tonnes, be very complex to deploy (say only above 1-2km altitude), very hard to inspect regularly etc. The other problem is, a lot of death/damage is done after plane hits the ground and starts to burn. You wouldn't be able to prevent that, since emergency parachute falls are hard ones. So you might still end up killing everybody on plane.
agumonkey 8y ago
costs and motivation I suppose some air vehicles have whole frame parachutes but not the scale of 737. I was wondering if a plane could not be made out of separate cabins coupled together (I can hear engineers die of laughter) so that they could be break loose with their own parachute.
- 8y ago

prmph 8y ago

Maybe this is a naive question, but why can't the automated controls on plane be designed such that: 1. They can be independently disabled? 2. For MCAS in particular, disabling it will automatically revert to the previous trim level before it shuts off? 3. They can rely on sensors that are kept in enclosed storage (thus much less likely to fail due to freezing, etc) and immediately deployed when there is a problem with the usual sensors? Like the RAM air turbine? Most auto-pilot malfunctions seem to be due to sensors going bad. Edit: Sorry I wasn't clearer the first time, but I meant the enclosed redundant sensors would be brought outside when needed, and retracted when not in use. Even the pitot tube could benefit from such a scheme

Neil44 8y ago
I guess it would be the complexity of the troubleshooting procedures involved if every feature had it's own disabler. You only have a short time under high pressure to resolve these issues so I can see that fewer, broader stroke options would be better.
crocal 8y ago
Implementor of similar systems here. 1. It's possible, but you have to understand that a pilot, however bright he may be, cannot be overloaded with too many modes of operations. You can't always have Neil Armstrong driving... 2. We have to wait for the conclusions of the investigation. There is obviously still a lot of question marks about what /should/ occur and what /did/ occur, so it's difficult to speculate (at least for me) on what a correct implementation of the system should have been. 3. Each sensor has pros and cons. For an AOA, I am not an expert, but well, it's supposed to measure the lift under the wing, so I don't see how you can avoid being outdoor to get a direct measure of this quantity. I believe someone on HN more expert could give more insight here, but my experience when you try to use indirect sensors is that it générâtes the need for /more/ computational complexity to deduce the intended measure from indirect sources. For your last comment, I would complement that auto pilots malfunction due to sensors going bad /unnoticed/. We should take "going bad" very broadly: either the sensor is broken, or it is not picking up something that it should because, well, the designer just did not think about it.

aaron695 8y ago

Currently we are quoting an Ethiopian Transport Minister. We should be worried that they are setting the narrative before the report is released. What people hear now will override what the report actually says tomorrow, a normal tactic of politicians. And even if you think capitalism means the airline will be world standard, at 114/179 on the corruption index I'd not trust their politicians. We get to check when the report comes out I guess.

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dis-sys 8y ago

With such new evidence, how FAA which refused to ground the 737 Max should be allowed to walk away from all these for nothing?

jki275 8y ago
The FAA did ground the 737 Max.
- dis-sys 8y ago
  FAA defended 737 Max to the very last minute, FAA is nothing else but a cheap tool for big corporations like Boeing.
  - jki275 8y ago
    The last minute when they grounded them? I don't recall them "defending" anything, anyway, they simply held off grounding them until they got a little bit of data to back it up.
    - dis-sys 8y ago
      > they simply held off grounding them until they got a little bit of data to back it up In my dictionary I have the following term which FAA and Boeing both actively ignored/violated. pre·cau·tion /prəˈkôSH(ə)n/ noun a measure taken in advance to prevent something dangerous, unpleasant, or inconvenient from happening.
      - jki275 8y ago
        You have to balance "precaution" with "knee-jerk".

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antocv 8y ago

Change the title please, now it reads as if the Ethiopian Airlines were at fault for "not stopping nosedive" Title should be "Boeing 737 nose-dived and crashed due to capitalism, killing Ethiopians".

SmellyGeekBoy 8y ago
The reason they were flying in the first place was due to capitalism. The reason you're able to read this story on this website is due to capitalism. I don't get your point.
matt4077 8y ago
Somehow your opinion of capitalism is on par with your idea that only Ethiopians fly on Ethopian Airlines.

markmm 8y ago

If this was a bug it would have presented in other airliners as software is an exact copy. Sound's like human or hardware fault.

rutthenut 8y ago

Some other info aggregated here https://www.theverge.com/2019/4/4/18294317/boeing-737-max-ethiopian-airlines-crash-report https://www.theverge.com/2019/4/4/18294317/boeing-737-max-et... Clear to most that the software has/had an appalling design for error-handling, with tragic results, and blame from Boeing to deflect that

draw_down 8y ago

After the second crash of this plane model within 6 months, the call to ground the 737 Max until we understand why the crashes happened was labeled an overreaction. As if safety should not be the first priority, as if abundance of caution is a bad thing. It was very interesting to watch this happen; I thought, why wouldn’t you want to be cautious? My take on it is there’s a “boy who cried wolf” effect where everything gets branded as over-the-top, unnecessary outrage, etc, that our judgement has been affected. Our ability to recognize and respond to truly exceptional circumstances is diminished. It’s so easy now to paint people as being hysterical or whatever, but sometimes cool calm and collected is actually not the correct stance.

hckr123 8y ago

Old news https://www.bloomberg.com/news/articles/2018-03-08/american-airlines-to-retire-45-boeing-737s-over-next-two-years https://www.bloomberg.com/news/articles/2018-03-08/american-... Just retire the whole plane

segmondy 8y ago

I thought this was a software failure initially, but upon following the case, I have come to realize it's not. I still see plenty of people saying this is a software failure in this thread. This is not a software failure. This is a system/process failure on many level. The plane was rushed to beat a competitor. A mismatch between the plane & engine happened which can cause it to be off balance. A system was added in place to correct it, but this system only used one sensor instead of 2. The display could have displayed angle of attack which is a safety gauge, but it's optional and was charged for. $80k on a $120 million plane. It's now standard. The display could also display a disagree light if the 2 sensors disagree, but that is also an optional feature, which will now be made standard. The MCSA was only suppose to adjust for .5 degrees and when Boeing & FAA worked together, this was the agreed parameter, but Boeing changed it after the fact to I believe 2.5 and never informed the FAA. FAA only discovered this after the Lion crash. This new system was not documented. It was not in the flight manual or training. Boeing lied to pilots when they asked if there's any new system they should know about. FAA wasn't through in certification process and allowed Boeing to sign off some things themselves. The failure was on so many levels it's ridiculous. It's a whole collapse of a system. Boeing, FAA, certification, QA, hardware design, etc. If anything I won't even blame the software team much, software has no choice but to rely on the signal it's reading from the sensor if invalid. My concern is that the plane wasn't tested with faulty sensor. A happy path was followed. Testing with faulty sensor data might have shown the tug of war that would have happened between the pilot & plane. All in all, failure is across so many levels, it's terrible.

salawat 8y ago
This has been just about my exact conclusion. I've just been checking things off as the evidence rolls in.