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There is strong evidence against the assumption that this should be something that a typical flight crew can handle, in the form of the smoldering wreckage of n

There is strong evidence against the assumption that this should be something that a typical flight crew can handle, in the form of the smoldering wreckage of not one but two planes, each with a trained, professional crew.

WalterBright 5y ago
You're right that there's something wrong with the training. There were 3 flights that had MCAS failure. All three were able to restore normal trim with the electric trim switches, which override MCAS. #1 turned off the trim system and continued the flight without incident. (This flight is almost never mentioned, as it doesn't fit the narrative.) #2 never turned off the trim system and crashed. At this point, an Emergency Airworthiness Directive was distributed to all MAX pilots instructing them to restore trim with the electric trim switches and then turn it off. #3 turned off the trim system when it was severely nose down, and crashed.
- salawat 5y ago
  >This flight is almost never mentioned, as it doesn't fit the narrative. It was mentioned repeatedly Walter; if not in the articles, then in the comments. The fact remains that afterward, when regulators put more pilots (two military and one civilian trained) pilots into single-event upset simulations, 1 of the three failed to recover the plane in time. If you acknowledge the training was faulty, then just let it be. Trim runaway presenting continuously vs. intermittently may not seem that important from a clean room engineer's perspective, but when viewed by a pilot through the lens of instruments, blaring alarms, and whatever else is going on in the cockpit, my engineer's optimism favors not relying on the human being perfect, or the defect only happening at a non-terminal part of the flight regime. It sucks that it played out the way it did. Maybe if someone would have spent as much time on MCAS and the pilot training as you did the 757 auto-trim, it wouldn't have been an issue. But they didn't. And innocents paid for it.
  - WalterBright 5y ago
    > 1 of the three failed to recover the plane in time Without more information on what the background and training of those pilots, and why the one failed, I'm afraid it's just an anecdote. In both crashes, the trim came on repeatedly and the crews repeatedly brought it back to normal with the electric trim switches. 25 times in the case of the LA crash. They obviously knew that the trim was the problem, because they took this corrective action. The trim running is obvious by the large black&white spinning wheels in the cockpit, and the deliberately loud clacking sound the running trim makes. All they had to do was then turn it off. > But they didn't. And innocents paid for it. That's right, and that's the tragedy. As to why they didn't, who knows. The stab trim cutoff switch is right there in a priority position on the console, because it's a damned important switch. Dealing with runaway trim is supposed to be a memory item, i.e. memorized. It does suggest a training problem.
    - salawat 5y ago
      Here's the article I was thinking of, though I think it was originally either in seattletimes or WSJ. http://airsoc.com/articles/view/id/5d5143c7c4263ce96fd616b6/newly-stringent-faa-tests-spur-a-fundamental-software-redesign-of-boeing-s-737-max-flight-controls http://airsoc.com/articles/view/id/5d5143c7c4263ce96fd616b6/... Differen source. https://aviationweek.com/air-transport/software-fix-will-address-most-recent-max-issue https://aviationweek.com/air-transport/software-fix-will-add... The civillian trained test pilot lost it. The two military pilots did not.
      - WalterBright 5y ago
        Thanks for the reference. I haven't seen this information before. "In one scenario, the bits chosen first told the computer that MCAS was engaged when it wasn’t. This had the effect of disabling the cut-off switches inside the pilot-control column, which normally stop any uncommanded movement of the horizontal tail if the pilot pulls in the opposite direction." The cutoff switches cannot be disabled on the airplane. "They flew the same fault scenario again, this time deliberately allowing the fault to run for some time before responding. This time, one of the three pilots didn’t manage to recover and lost the aircraft." That's kinda vague.
- MayeulC 5y ago
  IIRC, #1 also had an extra pilot at hand, and that extra pilot is the one who suggested turning off the trim system.
- oldsecondhand 5y ago
  > #1 turned off the trim system and continued the flight without incident. (This flight is almost never mentioned, as it doesn't fit the narrative.) I.e. they piloted the plane without the MCAS, which they were not trained to do. The whole reason of the existence of the MCAS is to avoid training the pilots to fly the planes without it.
  - salawat 5y ago
    This is the part that bugs me as well. When you have to disable MCAS, you're flying a plane you've not trained for. Particularly given the fact MCAS featured prominently in the landing regime.
  - throwaway0a5e 5y ago
    >I.e. they piloted the plane without the MCAS, which they were not trained to do. The whole reason of the existence of the MCAS is to avoid training the pilots to fly the planes without it. This kind of hand wringing shares a non-negligible part of the blame for why hundreds of people are dead. If Boeing had been allowed to say "of course our new engines are gonna pull the nose up a little harder, throttle back and climb slower if you don't like it" the MCAS system would never have been built to be the safety critical boondoggle it became. The plane itself handled just fine but the problem that they tried to solve with MCAS is that it wasn't identical to the prior 737. Even the most incompetent professional 737 pilot can fly a 737 that wants to <insert control input here> slightly when <insert other control input here> so long as they're expecting it (remember, they train for this stuff in simulator and most of these pilots are certified for multiple different aircraft) but just letting the pilots deal with it wasn't an option because the regulations disallowed that due in large part to decades of "people are just dumb cogs" type thinking. And once the airplanes started falling out of the sky nobody could say "just turn of MCAS, it won't handle the same but close enough" because Boeing, the airlines and the FAA were all so balls deep in the lie they'd look like idiots if they changed their opinions and thanks to the society we've cultivated nobody is willing to be the first to break formation because that's who gets targeted by the bulk of the fallout.
    - Gwypaas 5y ago
- caconym_ 5y ago
  I don't think GP is suggesting there was some issue with the training. I think they are suggesting that it's very difficult to justify MCAS (as originally implemented) as WAI when it quite clearly brought down two airplanes full of people. This seems a bit of a non sequitur from your first comment, but you did reply (here). I'm still not sure what your point is, though. What "narrative" are you referring to?
- hinkley 5y ago
  The classical problem in software and apparently in engineering is that some suit with a big mouth makes promises that can't be kept, and then makes everything difficult for everyone else by trying to make their lie true. Either people sacrifice their health, sanity and families bending over backward trying to cover for them, or some safety problem makes it into the product due to false constraints. The 737 Max was sold on not having to do certain kinds of retraining. "Something wrong with the training" is a divide by zero error here. There was no training. If memory serves this was also tied up in how much and what kind of recertification the FAA would require for a 'new' plane versus a refit of an existing one. Training means newness, and newness means retesting. The lies snowballed into dead passengers.

WalterBright 5y ago

You're right that there's something wrong with the training. There were 3 flights that had MCAS failure. All three were able to restore normal trim with the electric trim switches, which override MCAS. #1 turned off the trim system and continued the flight without incident. (This flight is almost never mentioned, as it doesn't fit the narrative.) #2 never turned off the trim system and crashed. At this point, an Emergency Airworthiness Directive was distributed to all MAX pilots instructing them to restore trim with the electric trim switches and then turn it off. #3 turned off the trim system when it was severely nose down, and crashed.

salawat 5y ago
>This flight is almost never mentioned, as it doesn't fit the narrative. It was mentioned repeatedly Walter; if not in the articles, then in the comments. The fact remains that afterward, when regulators put more pilots (two military and one civilian trained) pilots into single-event upset simulations, 1 of the three failed to recover the plane in time. If you acknowledge the training was faulty, then just let it be. Trim runaway presenting continuously vs. intermittently may not seem that important from a clean room engineer's perspective, but when viewed by a pilot through the lens of instruments, blaring alarms, and whatever else is going on in the cockpit, my engineer's optimism favors not relying on the human being perfect, or the defect only happening at a non-terminal part of the flight regime. It sucks that it played out the way it did. Maybe if someone would have spent as much time on MCAS and the pilot training as you did the 757 auto-trim, it wouldn't have been an issue. But they didn't. And innocents paid for it.
- WalterBright 5y ago
  > 1 of the three failed to recover the plane in time Without more information on what the background and training of those pilots, and why the one failed, I'm afraid it's just an anecdote. In both crashes, the trim came on repeatedly and the crews repeatedly brought it back to normal with the electric trim switches. 25 times in the case of the LA crash. They obviously knew that the trim was the problem, because they took this corrective action. The trim running is obvious by the large black&white spinning wheels in the cockpit, and the deliberately loud clacking sound the running trim makes. All they had to do was then turn it off. > But they didn't. And innocents paid for it. That's right, and that's the tragedy. As to why they didn't, who knows. The stab trim cutoff switch is right there in a priority position on the console, because it's a damned important switch. Dealing with runaway trim is supposed to be a memory item, i.e. memorized. It does suggest a training problem.
  - salawat 5y ago
    Here's the article I was thinking of, though I think it was originally either in seattletimes or WSJ. http://airsoc.com/articles/view/id/5d5143c7c4263ce96fd616b6/newly-stringent-faa-tests-spur-a-fundamental-software-redesign-of-boeing-s-737-max-flight-controls http://airsoc.com/articles/view/id/5d5143c7c4263ce96fd616b6/... Differen source. https://aviationweek.com/air-transport/software-fix-will-address-most-recent-max-issue https://aviationweek.com/air-transport/software-fix-will-add... The civillian trained test pilot lost it. The two military pilots did not.
    - WalterBright 5y ago
      Thanks for the reference. I haven't seen this information before. "In one scenario, the bits chosen first told the computer that MCAS was engaged when it wasn’t. This had the effect of disabling the cut-off switches inside the pilot-control column, which normally stop any uncommanded movement of the horizontal tail if the pilot pulls in the opposite direction." The cutoff switches cannot be disabled on the airplane. "They flew the same fault scenario again, this time deliberately allowing the fault to run for some time before responding. This time, one of the three pilots didn’t manage to recover and lost the aircraft." That's kinda vague.
MayeulC 5y ago
IIRC, #1 also had an extra pilot at hand, and that extra pilot is the one who suggested turning off the trim system.
oldsecondhand 5y ago
> #1 turned off the trim system and continued the flight without incident. (This flight is almost never mentioned, as it doesn't fit the narrative.) I.e. they piloted the plane without the MCAS, which they were not trained to do. The whole reason of the existence of the MCAS is to avoid training the pilots to fly the planes without it.
- salawat 5y ago
  This is the part that bugs me as well. When you have to disable MCAS, you're flying a plane you've not trained for. Particularly given the fact MCAS featured prominently in the landing regime.
- throwaway0a5e 5y ago
  >I.e. they piloted the plane without the MCAS, which they were not trained to do. The whole reason of the existence of the MCAS is to avoid training the pilots to fly the planes without it. This kind of hand wringing shares a non-negligible part of the blame for why hundreds of people are dead. If Boeing had been allowed to say "of course our new engines are gonna pull the nose up a little harder, throttle back and climb slower if you don't like it" the MCAS system would never have been built to be the safety critical boondoggle it became. The plane itself handled just fine but the problem that they tried to solve with MCAS is that it wasn't identical to the prior 737. Even the most incompetent professional 737 pilot can fly a 737 that wants to <insert control input here> slightly when <insert other control input here> so long as they're expecting it (remember, they train for this stuff in simulator and most of these pilots are certified for multiple different aircraft) but just letting the pilots deal with it wasn't an option because the regulations disallowed that due in large part to decades of "people are just dumb cogs" type thinking. And once the airplanes started falling out of the sky nobody could say "just turn of MCAS, it won't handle the same but close enough" because Boeing, the airlines and the FAA were all so balls deep in the lie they'd look like idiots if they changed their opinions and thanks to the society we've cultivated nobody is willing to be the first to break formation because that's who gets targeted by the bulk of the fallout.
  - Gwypaas 5y ago
caconym_ 5y ago
I don't think GP is suggesting there was some issue with the training. I think they are suggesting that it's very difficult to justify MCAS (as originally implemented) as WAI when it quite clearly brought down two airplanes full of people. This seems a bit of a non sequitur from your first comment, but you did reply (here). I'm still not sure what your point is, though. What "narrative" are you referring to?
hinkley 5y ago
The classical problem in software and apparently in engineering is that some suit with a big mouth makes promises that can't be kept, and then makes everything difficult for everyone else by trying to make their lie true. Either people sacrifice their health, sanity and families bending over backward trying to cover for them, or some safety problem makes it into the product due to false constraints. The 737 Max was sold on not having to do certain kinds of retraining. "Something wrong with the training" is a divide by zero error here. There was no training. If memory serves this was also tied up in how much and what kind of recertification the FAA would require for a 'new' plane versus a refit of an existing one. Training means newness, and newness means retesting. The lies snowballed into dead passengers.