12 ms·

>Though I can’t help but wonder if this is a very subtle re-framing of the Max accidents to shift blame back towards pilots. Blame is a loaded word. Boeing as

by treis 7y ago

>Though I can’t help but wonder if this is a very subtle re-framing of the Max accidents to shift blame back towards pilots. Blame is a loaded word. Boeing assumed that pilots could be relied upon to recover from a MCAS induced runaway trim. Practice has shown that they can't. Whether Boeing or the pilots is at fault is, from a safety perspective, irrelevant. The bottom line is that an assumption was made, it was wrong, and a couple planes crashed. Using average pilots instead of highly experienced test pilots is a sensible step to prevent a repeat.

kayfox 7y ago
To be more precise, Boeing assumed that all pilots flying their aircraft would be up to the standards of the United States as opposed to the different standards around the world.
- jfim 7y ago
  Has there been a documented occurrence of a US pilot encountering an MCAS failure in the US and correctly dealing with it?
  - pdonis 7y ago
    Yes, there are many reported incidents from US pilots of stability trim incidents in the FAA's database which, in hindsight, were due to MCAS. The pilots couldn't identify them as such at the time because, of course, they didn't know MCAS existed. But they were able to figure out the corrective action in time to maintain safe flight. (The reports also criticize the flight manual for being inadequate.) https://www.google.com/search?client=ubuntu&channel=fs&q=us+pilots+mcas+incidents&ie=utf-8&oe=utf-8 https://www.google.com/search?client=ubuntu&channel=fs&q=us+...
    - kayfox 7y ago
      Most of those reports involved the autopilot or were while flaps were extended, which disables MCAS. The ones that did not were complaining about not being informed about MCAS and not about it actuating. There were even incidents reported as being MCAS that did not involve stabilizer trim or a 737 MAX.
      - pdonis 7y ago
        Reports like the one where the plane started descending when autopilot was engaged are still relevant because they indicate issues with the angle of attack sensor, which is also what MCAS relies on.
        kayfox 7y ago
        AoA sensors are notoriously unreliable and Boeing should not have depended on just one.
        pdonis 7y ago
        Yes, definitely.
    - davinic 7y ago
      Also all of the US-based MAXs had the optional AoA Sensor Disagree indicator, which would instantly show the source of the issue. The international pilots were in the dark because Boeing turned a critical safety feature into a revenue stream.
      - kayfox 7y ago
        AoA Disagree was supposed to be turned on on all 737 MAXs, but it depended on AoA indication, which was an option. This was a mistake Boeing admitted to and has since corrected. Options are not all tied to fees, the process of ordering an airplane is quite complicated because of the immense amount of customization each airline does before they even pay for the aircraft. Its unclear how much this option cost, if it cost anything. The reason why AoA indication is an option is that it requires more advanced training for the pilots, some airlines provide this training and some do not. The airlines are the ultimate decider on how much training pilots will get, Boeing and the FAA can only set minimums.
        computerex 7y ago
        Do you have any official sources to support anything you're saying? It seems unbelievable to me that Boeing would introduce MCAS, a complete flight characteristics "augmentation" system and pass it off as a standard 737 without any special training, but would only offer AoA indication as an option due to training.
  - kayfox 7y ago
    As far as anyone could tell, MCAS was not encountered before in the US.
- throw0101a 7y ago
  Or perhaps assumed that the pilots even knew that the MCAS existed and how to override it. Part of the debate is that Boeing told the FAA and everybody else that 'no special training' for the Max series was needed; just watch a couple-hour video or somesuch.
- JanSt 7y ago
  My understanding is that the pilots had only about 40 seconds time to solve the problem and were trained for one hour with an iPad (not on the MCAS, but the whole 737 Max). I'm not sure whether this is a question of pilots' standards in the US vs around the world.
  - kayfox 7y ago
    The general idea was that pilots would correctly recognize large amounts of undesired and uncommanded trim being runaway trim and perform the checklist to resolve that issue that they are expected to know by memory, since there is a need to execute it fast, without paging through the Quick Reference Handbook. This is not a checklist that was introduced with the 737 MAX, but one that has existed since the introduction of the 737 in 1969. I haven't gone and checked but IIRC a similar checklist exists for all Boeing jetliners and I would expect Airbus as well. In any system failure there is a chain of events that leads up to the ultimate failure, concentrating solely on Boeing's mistakes in these crashes overlooks all the other points at which they could have been averted: 1. In the Lion Air crash, there were some significant maintenance issues that lead up to the replacement for a failing AoA sensor with a used part older than the aircraft failing as well. 2. There were some significant failings in Crew Resource Management in the accident flights. 3. There appear to be issues in the pilots abilities to deal with unexpected situations. This is why simulator training exists, so that pilots can encounter unexpected issues and deal with them correctly. 4. The failure that lead to MCAS being activated also caused a whole ton of warnings to be activated, which may have been a situation Boeing was not expecting, and therefore did not put into the minimum baseline training they create. 5. The flight computer system and MCAS was implemented problematically, relying on one input because the expected control authority was very low, and then when that was not changed the system was not re-architected. 6. Boeing's designs reflect a US-centric expectation of pilots. In the US we expect pilots flying airliners to have spent at least 1500 hours flying before they can even sit in the co-pilot seat. In other parts of the world I have heard numbers as low as 240 hours, so pilot testing will need to reflect this going forward.
    - ClumsyPilot 7y ago
      > 5. 5. The flight computer system and MCAS was implemented problematically, relying on one input because the expected control authority was very low, and then when that was not changed the system was not re-architected. I like your approach: Pilot's failures caused the crash, and Boeing made an honest mistake. And you seem to think it would have been fine flying in the US. You do realise plane crashes and industrial accidents do happen in the US? A safe system assumes they are operated by humans who are not infallible, and should not go up in flames from minor issues. Otherwise we must conclude Chernobyl reactor was a perfectly fine design.
- chopin 7y ago
  From what I read, I'd assume that the US just got lucky.
elbrian 7y ago
> Boeing assumed that pilots could be relied upon to recover from a MCAS induced runaway trim. Practice has shown that they can't. Whether Boeing or the pilots is at fault is, from a safety perspective, irrelevant. From a practical perspective, however, Boeing making universal assumptions about pilot capabilities in life-or-death situations, utilizing new equipment that they were not trained on, is anything but irrelevant.
- treis 7y ago
  Their logic was that pilots are trained to deal with runaway trim, a MCAS failure is runaway trim, ergo pilots are trained to deal with a MCAS failure. Obviously that logic turned out to be faulty but it's not like Boeing made some outlandish leap here.
  - erikpukinskis 7y ago
    Do you really think that’s an appropriate level of analysis for the manufacturer of a brand new MCAS? “Any failure of this new thing we’re shipping is just a trim failure, pilots can handle it”?
    - treis 7y ago
      With the benefit of hindsight it looks obviously wrong, but without that the reasoning looks sound to me. IMHO, the failure lies in validating the analysis with realistic test conditions. They should be testing their assumptions against the worst pilots, not the best.
      - makomk 7y ago
        The problem with their testing wasn't just that they tested against the best pilots. They simulated MCAS failure as just the stabilizer trim running away, which of course their test pilots caught. Real-world MCAS failures were accompanied by a bunch of warnings about loss of accurate airspeed and altitude (because those also used the angle-of-attack sensor), which meant that in reality pilots were occupied trying to sort through that and figure out if any of the conflicting airspeed and altitude readings could be trusted. That is, as I understand it, hard enough to deal with and demanding enough on its own that even well-trained Western pilots screw it up, occasionally with tragic results. Then whilst all that's happening they're meant to notice that the trim wheel is moving in an uncommanded and unwanted fashion, turn electric trim off, and manually wrestle the trim wheel back into the correct position (whatever that even is). Boeing didn't simulate any of those added complications according to the NTSB.
dahart 7y ago
I appreciate the attempt to be diplomatic, and I agree that using average pilots is sensible. But, with respect, I could not disagree more with the rest of that. > Blame is a loaded word. Boeing’s response to the accidents was to blame the pilots, there is precedent for this word in this situation. https://www.cnn.com/2019/05/23/business/american-airlines-boeing-pilots-union/index.html https://www.cnn.com/2019/05/23/business/american-airlines-bo... > Boeing assumed that pilots could be relied upon No, Boeing intentionally hid information from pilots. This is well known. https://www.wsj.com/articles/boeing-withheld-information-on-737-model-according-to-safety-experts-and-others-1542082575 https://www.wsj.com/articles/boeing-withheld-information-on-... > Whether Boeing or the pilots is at fault is, from a safety perspective, irrelevant No. If you want to fix the problem, you must know what the problem is. The cause may be irrelevant to the people who are dead, but it is absolutely relevant to solving the problem in the future especially from a safety perspective.
- totally 7y ago
  It sounds like you're advocating for blame-ful post mortems. Is that the case and what's your reasoning?
  - aeonsky 7y ago
    Yes, when 400 people die for a company to save money, you must assign blame and put people in jail.
    - fennecfoxen 7y ago
      I have downvoted your comment, because I believe it does more to obscure understanding than to enlighten. > when 400 people die for a company to save money Let me take a step back and ask: Why? Is it because we're vindictive, and demand blood? Or is it because this actually does something to help keep people from dying in the future? If the latter is more important than the former -- which I hope is the case -- how can we trust that we're pursuing a course that improves the future of society while also using rhetoric to the effect of "when 400 people die for a company to save money"? Consider, for instance: Part of reason for the company "saving money" is that it results in lower costs for planes, and ultimately lower airfare for customers who pay airlines' capital expenses, potentially resulting in fewer miles driven and fewer accident. Is reducing this statistical danger more or less than the danger of the planes? Quite possibly, it's not -- but using this rhetoric certainly won't help us find out. More broadly the "omg greed" narrative, which -- to me, at least -- just doesn't make too much sense. If the corner-cutting that led to 737 Max problems is to be understood as a "greed" move, it's a pretty incompetent one, because Boeing is almost certainly out billions over the mess. People who seek to maximize profits for their own self-interest also seek to mitigate risk, for the same reason. I would suggest that a "hubris" narrative, or something similar, is probably more appropriate here. If this is so, the remedies are entirely different, and the assertion that we MUST jail people, because it fits our "greed" narrative and whatever cognitive bias we drag into the picture, ensures that we will not remedy the problem effectively. This means people may die.
StreamBright 7y ago
You cannot really assume such thing in a situation like flying when the consequences of your assumption is loss of life potentially.
ryacko 7y ago
>Boeing assumed that pilots could be relied upon to recover from a MCAS induced runaway trim. The incidents of MCAS errors with US pilots who reported it to the FAA did result in recovery. But later cases did result in tragic accidents. https://static.seattletimes.com/wp-content/uploads/2018/11/LionAir-BlackBox-WEB-1020x680.jpg https://static.seattletimes.com/wp-content/uploads/2018/11/L... But when you make that statement, I don't think you're really imagining what it would be like to be on a plane like that. The above infographic shows what it is like. The plane was operating in an erratic manner. I don't design planes, but does Boeing at least have a system that detects whether or not pilots are resisting against the controls?
- salawat 7y ago
  They did actually. Older 737 models have an "oh shit" trim override when the pilot pulls the yoke back. This was specifically removed from the MAX to accommodate MCAS.
sterileopinions 7y ago
>Whether Boeing or the pilots is at fault is, from a safety perspective, irrelevant. It's quite literally the most relevant talking point in this entire conversation.
markdown 7y ago
> Using average pilots instead of highly experienced test pilots is a sensible step to prevent a repeat. It wouldn't have made a difference without the training for this specific MCAS issue. Highly experienced test pilots would have been equally unable to recover had they been flying the planes that crashed. Normal runaway trim is easily handled, but the MCAS-induced runaway trip had the cockpit lighting up with all sorts of errors and warning lights and beeps. The only way to deal with this is to pick up checklists and start going through them... which you simply couldn't do because there was no time. So using pilots selected at random from various airlines is a great idea and should be implemented, but it would not have prevented this situation. Only training might have.
smaddox 7y ago
> Using average pilots instead of highly experienced test pilots is a sensible step to prevent a repeat. Or a good way to kill average pilots. How about using highly skilled pilots, but failing a plane when anything unusual happens?

by treis 7y ago

kayfox 7y ago

To be more precise, Boeing assumed that all pilots flying their aircraft would be up to the standards of the United States as opposed to the different standards around the world.

jfim 7y ago
Has there been a documented occurrence of a US pilot encountering an MCAS failure in the US and correctly dealing with it?
- pdonis 7y ago
  Yes, there are many reported incidents from US pilots of stability trim incidents in the FAA's database which, in hindsight, were due to MCAS. The pilots couldn't identify them as such at the time because, of course, they didn't know MCAS existed. But they were able to figure out the corrective action in time to maintain safe flight. (The reports also criticize the flight manual for being inadequate.) https://www.google.com/search?client=ubuntu&channel=fs&q=us+pilots+mcas+incidents&ie=utf-8&oe=utf-8 https://www.google.com/search?client=ubuntu&channel=fs&q=us+...
  - kayfox 7y ago
    Most of those reports involved the autopilot or were while flaps were extended, which disables MCAS. The ones that did not were complaining about not being informed about MCAS and not about it actuating. There were even incidents reported as being MCAS that did not involve stabilizer trim or a 737 MAX.
    - pdonis 7y ago
      Reports like the one where the plane started descending when autopilot was engaged are still relevant because they indicate issues with the angle of attack sensor, which is also what MCAS relies on.
      - kayfox 7y ago
        AoA sensors are notoriously unreliable and Boeing should not have depended on just one.
        pdonis 7y ago
        Yes, definitely.
  - davinic 7y ago
    Also all of the US-based MAXs had the optional AoA Sensor Disagree indicator, which would instantly show the source of the issue. The international pilots were in the dark because Boeing turned a critical safety feature into a revenue stream.
    - kayfox 7y ago
      AoA Disagree was supposed to be turned on on all 737 MAXs, but it depended on AoA indication, which was an option. This was a mistake Boeing admitted to and has since corrected. Options are not all tied to fees, the process of ordering an airplane is quite complicated because of the immense amount of customization each airline does before they even pay for the aircraft. Its unclear how much this option cost, if it cost anything. The reason why AoA indication is an option is that it requires more advanced training for the pilots, some airlines provide this training and some do not. The airlines are the ultimate decider on how much training pilots will get, Boeing and the FAA can only set minimums.
      - computerex 7y ago
        Do you have any official sources to support anything you're saying? It seems unbelievable to me that Boeing would introduce MCAS, a complete flight characteristics "augmentation" system and pass it off as a standard 737 without any special training, but would only offer AoA indication as an option due to training.
- kayfox 7y ago
  As far as anyone could tell, MCAS was not encountered before in the US.
throw0101a 7y ago
Or perhaps assumed that the pilots even knew that the MCAS existed and how to override it. Part of the debate is that Boeing told the FAA and everybody else that 'no special training' for the Max series was needed; just watch a couple-hour video or somesuch.
JanSt 7y ago
My understanding is that the pilots had only about 40 seconds time to solve the problem and were trained for one hour with an iPad (not on the MCAS, but the whole 737 Max). I'm not sure whether this is a question of pilots' standards in the US vs around the world.
- kayfox 7y ago
  The general idea was that pilots would correctly recognize large amounts of undesired and uncommanded trim being runaway trim and perform the checklist to resolve that issue that they are expected to know by memory, since there is a need to execute it fast, without paging through the Quick Reference Handbook. This is not a checklist that was introduced with the 737 MAX, but one that has existed since the introduction of the 737 in 1969. I haven't gone and checked but IIRC a similar checklist exists for all Boeing jetliners and I would expect Airbus as well. In any system failure there is a chain of events that leads up to the ultimate failure, concentrating solely on Boeing's mistakes in these crashes overlooks all the other points at which they could have been averted: 1. In the Lion Air crash, there were some significant maintenance issues that lead up to the replacement for a failing AoA sensor with a used part older than the aircraft failing as well. 2. There were some significant failings in Crew Resource Management in the accident flights. 3. There appear to be issues in the pilots abilities to deal with unexpected situations. This is why simulator training exists, so that pilots can encounter unexpected issues and deal with them correctly. 4. The failure that lead to MCAS being activated also caused a whole ton of warnings to be activated, which may have been a situation Boeing was not expecting, and therefore did not put into the minimum baseline training they create. 5. The flight computer system and MCAS was implemented problematically, relying on one input because the expected control authority was very low, and then when that was not changed the system was not re-architected. 6. Boeing's designs reflect a US-centric expectation of pilots. In the US we expect pilots flying airliners to have spent at least 1500 hours flying before they can even sit in the co-pilot seat. In other parts of the world I have heard numbers as low as 240 hours, so pilot testing will need to reflect this going forward.
  - ClumsyPilot 7y ago
    > 5. 5. The flight computer system and MCAS was implemented problematically, relying on one input because the expected control authority was very low, and then when that was not changed the system was not re-architected. I like your approach: Pilot's failures caused the crash, and Boeing made an honest mistake. And you seem to think it would have been fine flying in the US. You do realise plane crashes and industrial accidents do happen in the US? A safe system assumes they are operated by humans who are not infallible, and should not go up in flames from minor issues. Otherwise we must conclude Chernobyl reactor was a perfectly fine design.
chopin 7y ago
From what I read, I'd assume that the US just got lucky.

elbrian 7y ago

> Boeing assumed that pilots could be relied upon to recover from a MCAS induced runaway trim. Practice has shown that they can't. Whether Boeing or the pilots is at fault is, from a safety perspective, irrelevant. From a practical perspective, however, Boeing making universal assumptions about pilot capabilities in life-or-death situations, utilizing new equipment that they were not trained on, is anything but irrelevant.

treis 7y ago
Their logic was that pilots are trained to deal with runaway trim, a MCAS failure is runaway trim, ergo pilots are trained to deal with a MCAS failure. Obviously that logic turned out to be faulty but it's not like Boeing made some outlandish leap here.
- erikpukinskis 7y ago
  Do you really think that’s an appropriate level of analysis for the manufacturer of a brand new MCAS? “Any failure of this new thing we’re shipping is just a trim failure, pilots can handle it”?
  - treis 7y ago
    With the benefit of hindsight it looks obviously wrong, but without that the reasoning looks sound to me. IMHO, the failure lies in validating the analysis with realistic test conditions. They should be testing their assumptions against the worst pilots, not the best.
    - makomk 7y ago
      The problem with their testing wasn't just that they tested against the best pilots. They simulated MCAS failure as just the stabilizer trim running away, which of course their test pilots caught. Real-world MCAS failures were accompanied by a bunch of warnings about loss of accurate airspeed and altitude (because those also used the angle-of-attack sensor), which meant that in reality pilots were occupied trying to sort through that and figure out if any of the conflicting airspeed and altitude readings could be trusted. That is, as I understand it, hard enough to deal with and demanding enough on its own that even well-trained Western pilots screw it up, occasionally with tragic results. Then whilst all that's happening they're meant to notice that the trim wheel is moving in an uncommanded and unwanted fashion, turn electric trim off, and manually wrestle the trim wheel back into the correct position (whatever that even is). Boeing didn't simulate any of those added complications according to the NTSB.

dahart 7y ago

I appreciate the attempt to be diplomatic, and I agree that using average pilots is sensible. But, with respect, I could not disagree more with the rest of that. > Blame is a loaded word. Boeing’s response to the accidents was to blame the pilots, there is precedent for this word in this situation. https://www.cnn.com/2019/05/23/business/american-airlines-boeing-pilots-union/index.html https://www.cnn.com/2019/05/23/business/american-airlines-bo... > Boeing assumed that pilots could be relied upon No, Boeing intentionally hid information from pilots. This is well known. https://www.wsj.com/articles/boeing-withheld-information-on-737-model-according-to-safety-experts-and-others-1542082575 https://www.wsj.com/articles/boeing-withheld-information-on-... > Whether Boeing or the pilots is at fault is, from a safety perspective, irrelevant No. If you want to fix the problem, you must know what the problem is. The cause may be irrelevant to the people who are dead, but it is absolutely relevant to solving the problem in the future especially from a safety perspective.

totally 7y ago
It sounds like you're advocating for blame-ful post mortems. Is that the case and what's your reasoning?
- aeonsky 7y ago
  Yes, when 400 people die for a company to save money, you must assign blame and put people in jail.
  - fennecfoxen 7y ago
    I have downvoted your comment, because I believe it does more to obscure understanding than to enlighten. > when 400 people die for a company to save money Let me take a step back and ask: Why? Is it because we're vindictive, and demand blood? Or is it because this actually does something to help keep people from dying in the future? If the latter is more important than the former -- which I hope is the case -- how can we trust that we're pursuing a course that improves the future of society while also using rhetoric to the effect of "when 400 people die for a company to save money"? Consider, for instance: Part of reason for the company "saving money" is that it results in lower costs for planes, and ultimately lower airfare for customers who pay airlines' capital expenses, potentially resulting in fewer miles driven and fewer accident. Is reducing this statistical danger more or less than the danger of the planes? Quite possibly, it's not -- but using this rhetoric certainly won't help us find out. More broadly the "omg greed" narrative, which -- to me, at least -- just doesn't make too much sense. If the corner-cutting that led to 737 Max problems is to be understood as a "greed" move, it's a pretty incompetent one, because Boeing is almost certainly out billions over the mess. People who seek to maximize profits for their own self-interest also seek to mitigate risk, for the same reason. I would suggest that a "hubris" narrative, or something similar, is probably more appropriate here. If this is so, the remedies are entirely different, and the assertion that we MUST jail people, because it fits our "greed" narrative and whatever cognitive bias we drag into the picture, ensures that we will not remedy the problem effectively. This means people may die.

StreamBright 7y ago

You cannot really assume such thing in a situation like flying when the consequences of your assumption is loss of life potentially.

ryacko 7y ago

>Boeing assumed that pilots could be relied upon to recover from a MCAS induced runaway trim. The incidents of MCAS errors with US pilots who reported it to the FAA did result in recovery. But later cases did result in tragic accidents. https://static.seattletimes.com/wp-content/uploads/2018/11/LionAir-BlackBox-WEB-1020x680.jpg https://static.seattletimes.com/wp-content/uploads/2018/11/L... But when you make that statement, I don't think you're really imagining what it would be like to be on a plane like that. The above infographic shows what it is like. The plane was operating in an erratic manner. I don't design planes, but does Boeing at least have a system that detects whether or not pilots are resisting against the controls?

salawat 7y ago
They did actually. Older 737 models have an "oh shit" trim override when the pilot pulls the yoke back. This was specifically removed from the MAX to accommodate MCAS.

sterileopinions 7y ago

>Whether Boeing or the pilots is at fault is, from a safety perspective, irrelevant. It's quite literally the most relevant talking point in this entire conversation.

markdown 7y ago

> Using average pilots instead of highly experienced test pilots is a sensible step to prevent a repeat. It wouldn't have made a difference without the training for this specific MCAS issue. Highly experienced test pilots would have been equally unable to recover had they been flying the planes that crashed. Normal runaway trim is easily handled, but the MCAS-induced runaway trip had the cockpit lighting up with all sorts of errors and warning lights and beeps. The only way to deal with this is to pick up checklists and start going through them... which you simply couldn't do because there was no time. So using pilots selected at random from various airlines is a great idea and should be implemented, but it would not have prevented this situation. Only training might have.

smaddox 7y ago

> Using average pilots instead of highly experienced test pilots is a sensible step to prevent a repeat. Or a good way to kill average pilots. How about using highly skilled pilots, but failing a plane when anything unusual happens?