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> 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

> 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.
      - perl4ever 7y ago
        Doing X number of complicated routine things at once, in general, is infinitely easier than any situation where you are suddenly told "part of your system isn't reliable, now come up with a new model of what you can trust on the fly". It boggles me how people can't put themselves in the place of someone in the latter situation. Like, even if you haven't crashed a plane, haven't you experienced something similar on a small scale? Haven't you observed other people with such problems?
- computerex 7y ago
  I think they made a very outlandish leap and that resulted in hundreds of lives being lost. There is no room for assumptions when it comes to flight procedures.
- hitekker 7y ago
  > it's not like Boeing made some outlandish leap here. Your attempts to whitewash Boeing's negligence seems rather dishonest.
- olliej 7y ago
  Boeing did though - they decided unintentional trim was the same as a flight system that was deliberately hidden from the pilots was just a “trim” issue. They needed to classify it as a ordinary trim problem because otherwise they would have needed to have testing for it, which would have meant acknowledging MCAS existed. The evidence that it wasn’t just a normal trim issue is the second crash, which occurred when pilots already knew about the design fault. When it turned out that it wasn’t physically possible for a pilot to take the corrective actions. Boeing is still trying to blame the pilots for their own decision to fraudulently sell an unsafe aircraft.
- justesjc 7y ago
  It seems to me that your statement has some assumptions that may not be true, that a MCAS failure caused runaway trim would be recognized as such by the pilots. The ultimate issue may be a runaway trim, but a MCAS failure may not produce the normal indicators that would lead the pilots to diagnose the failure correctly within the time available. Assuming that a MCAS failure is the same thing as a runaway trim failure and should have been handled by the pilots, while technically correct, might not be an appropriate conclusion.
- dahart 7y ago
  You're right. Boeing did not make an outlandish leap of logic, or any leap of logic at all in this context, because it was fully their intent to get away with no training. They worked their butts off to minimize the training, to minimize even the very idea that training was needed, and to prevent the Max from having to be re-certified by the FAA.
  - bdamm 7y ago
    Of course, we can just as easily blame the FAA. If it's so hard to establish a differential training program then maybe the re-certification program the FAA requires (to certify a pilot to fly a slightly different aircraft) is too onerous. It's easy for the government to require too much work and seize up innovation, and I think we see that at work here. If the re-certification program wasn't so onerous, we could have seen Boeing put in some new warning conditions, or a better control layout that more clearly indicates the presence and activation of the MCAS, train pilots on that, and have a better, safer, airplane.
    - dahart 7y ago
      The FAA definitely bears some responsibility, but not because the regulation is too stringent, it’s because they looked the other way. Recertification is onerous for a reason; it’s safety we’re talking about, and the result of not being careful enough is exactly what happened, hundreds of deaths. The FAA’s process in this case is already a product of regulatory capture; Boeing is already practically certifying themselves. Lots of reporting on this already; it’s easy to find more info.

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.
    - perl4ever 7y ago
      Doing X number of complicated routine things at once, in general, is infinitely easier than any situation where you are suddenly told "part of your system isn't reliable, now come up with a new model of what you can trust on the fly". It boggles me how people can't put themselves in the place of someone in the latter situation. Like, even if you haven't crashed a plane, haven't you experienced something similar on a small scale? Haven't you observed other people with such problems?
computerex 7y ago
I think they made a very outlandish leap and that resulted in hundreds of lives being lost. There is no room for assumptions when it comes to flight procedures.
hitekker 7y ago
> it's not like Boeing made some outlandish leap here. Your attempts to whitewash Boeing's negligence seems rather dishonest.
olliej 7y ago
Boeing did though - they decided unintentional trim was the same as a flight system that was deliberately hidden from the pilots was just a “trim” issue. They needed to classify it as a ordinary trim problem because otherwise they would have needed to have testing for it, which would have meant acknowledging MCAS existed. The evidence that it wasn’t just a normal trim issue is the second crash, which occurred when pilots already knew about the design fault. When it turned out that it wasn’t physically possible for a pilot to take the corrective actions. Boeing is still trying to blame the pilots for their own decision to fraudulently sell an unsafe aircraft.
justesjc 7y ago
It seems to me that your statement has some assumptions that may not be true, that a MCAS failure caused runaway trim would be recognized as such by the pilots. The ultimate issue may be a runaway trim, but a MCAS failure may not produce the normal indicators that would lead the pilots to diagnose the failure correctly within the time available. Assuming that a MCAS failure is the same thing as a runaway trim failure and should have been handled by the pilots, while technically correct, might not be an appropriate conclusion.
dahart 7y ago
You're right. Boeing did not make an outlandish leap of logic, or any leap of logic at all in this context, because it was fully their intent to get away with no training. They worked their butts off to minimize the training, to minimize even the very idea that training was needed, and to prevent the Max from having to be re-certified by the FAA.
- bdamm 7y ago
  Of course, we can just as easily blame the FAA. If it's so hard to establish a differential training program then maybe the re-certification program the FAA requires (to certify a pilot to fly a slightly different aircraft) is too onerous. It's easy for the government to require too much work and seize up innovation, and I think we see that at work here. If the re-certification program wasn't so onerous, we could have seen Boeing put in some new warning conditions, or a better control layout that more clearly indicates the presence and activation of the MCAS, train pilots on that, and have a better, safer, airplane.
  - dahart 7y ago
    The FAA definitely bears some responsibility, but not because the regulation is too stringent, it’s because they looked the other way. Recertification is onerous for a reason; it’s safety we’re talking about, and the result of not being careful enough is exactly what happened, hundreds of deaths. The FAA’s process in this case is already a product of regulatory capture; Boeing is already practically certifying themselves. Lots of reporting on this already; it’s easy to find more info.