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Thanks for giving the link to the document. Looking at the context, the sentence you quoted is more a built-in disclaimer than a procedure that the pilots were

by acqq 6y ago

Thanks for giving the link to the document. Looking at the context, the sentence you quoted is more a built-in disclaimer than a procedure that the pilots were supposed to learn to apply in only a few seconds they would have before the airplane crashes to the ground for overriding pilot close to the ground. After all the changes, it's at the end, and uses the weaseling "may be needed" and "can be used". We saw that not doing very specific sequence in a few seconds makes the plane non steerable. Edit: Answering: "The LA pilots worked the problem for 5 minutes, the EA 2 minutes. Quite a bit more than seconds." They "worked the problem" during that time by actively attempting to prevent the plane to crash. It's surely not that they simply had that much time to think about what to do next. Also, during most of that time of "minutes", if I remember correctly, the plane was most of the time actively turning to the ground, overriding their attempts to force it flying in the safe direction and doing that repeatedly. I really don't see that for these two accidents it can be said that it was "a pilot error" and I don't see any institution claiming that publicly anymore, even if some would really, really like to be able to do that and would immediately do, if it were possible. "Two simple steps"? Well "may be needed" and "can be used" is surely not even "after X happens do P and then do Q, if not exactly done in that sequence and at that point, the plane will surely crash." Nobody had the training to fight against the program that every time they straightened the plane up turned it back to the ground, making the manual trim impossible to be applied.

WalterBright 6y ago
The LA pilots worked the problem for 5 minutes, the EA 2 minutes. Quite a bit more than seconds. Frankly, I'm baffled by the EA pilots. If I was a MAX pilot, and I received an EMERGENCY AIRWORTHINESS DIRECTIVE about how to not crash like LA pilots, it's my job to read, understand, and remember those instructions. And not just my job, it'd save my own life, too. It's not like it's complicated, either. Two simple steps. After all, what would you do?
- bkor 6y ago
  A crash is not due to one cause. Multiple things have to fail for this to be a problem. Blaming pilots is way too simplistic. The design of those warnings were highly confusing and overwhelming. Saying "oh, just have better pilots" it NOT good enough. It should be as per the Swiss cheese theory where multiple things should fail before there's a problem. Further, not hide things like MCAS, downplay the need for additional training, refuse additional training when requested, change MCAS without notifying FAA, pressure people into being quick over safe, design MCAS to rely on a sensor, have a critical system (MCAS) rely on one sensor despite this not being allowed (critical systems MUST have multiple sensor inputs), etc. But yeah, it was the pilots not reading a message. Looking back, MCAS was not a good idea. But whatever led up to MCAS might have given the 737 MAX also some other bad changes. At the moment we don't know, maybe in future it'll be "obviously aside from MCAS the 737 MAX should also have a fix for X".
  - WalterBright 6y ago
    > A crash is not due to one cause. Multiple things have to fail for this to be a problem. You're entirely correct. > Blaming pilots is way too simplistic. Also correct, but in my opinion the pilots were one of the multiple causes of the accidents, based on the published accounts of their actions. Ignoring Emergency Airworthiness Directives is inexcusable. Ignoring EADs is a problem that should be dealt with as part of the corrective actions required by the FAA. Recall that immediately prior to the LA crash, the previous flight crew on the same airplane had the same problem, dealt with it, and landed safely. (That was also before the EAD was issued.) Let me put it another way - would you want to get on an airplane with a crew that didn't pay attention to Emergency Airworthiness Directives? I wouldn't. And yes, Boeing must fix the MCAS system. I'm not excusing Boeing's role in the accidents.
  - acqq 6y ago
    > it was the pilots not reading a message. It was that the message (see the whole, the link was quoted) definitely wasn't clear. It has multiple weasel words and it is far from a clear and actionable sequence checklist for the exact condition in which two planes were put due to the MCAS. Only with the hindsight of knowing how two accidents developed and the independent pilots trying to reconstruct on the simulators these events it can be claimed that that formulation described something usable. Just with the pilots "reading it" at that time and even having it in front of them at the moment of the accident, without any special training for that situation (where the plane multiple times "undoes" the actions of the pilot, orienting the plane toward ground as the plane is still flying low) it's still improbable that the accident wouldn't happen. Note: It's Boeing who insisted that the training for MCAS is not needed.
    - WalterBright 6y ago
      It's written in airplane jargon, of course, but it's plenty clear. > It's Boeing who insisted that the training for MCAS is not needed. It's not completely unreasonable to expect the pilots to be able to handle runaway trim, especially given an EMERGENCY AIRWORTHINESS DIRECTIVE reiterating how to do it. Runaway trim is a critical problem, which is why the electric trim switches are there as well as the cutoff switches, all in easy reach. Dealing with this is supposed to be a "memory item", meaning something the pilots must know. But clearly in hindsight, dealing with runaway trim must be specifically and better trained for. > special training The thing about runaway trim is it turns on when it's not supposed to. That's why the electric trim overrides are there and the cutoff switches. Those are there for all Boeing jets since electric trim was installed going back to at least 1960 and probably much earlier. When I worked on the stabilizer trim system on the 757, I worked mostly on the gearbox, but was peripherally involved with the electrical system for it. The cutoff switches were there for "when demons possess the control system and try to drive you into the ground."

by acqq 6y ago

WalterBright 6y ago

The LA pilots worked the problem for 5 minutes, the EA 2 minutes. Quite a bit more than seconds. Frankly, I'm baffled by the EA pilots. If I was a MAX pilot, and I received an EMERGENCY AIRWORTHINESS DIRECTIVE about how to not crash like LA pilots, it's my job to read, understand, and remember those instructions. And not just my job, it'd save my own life, too. It's not like it's complicated, either. Two simple steps. After all, what would you do?

bkor 6y ago
A crash is not due to one cause. Multiple things have to fail for this to be a problem. Blaming pilots is way too simplistic. The design of those warnings were highly confusing and overwhelming. Saying "oh, just have better pilots" it NOT good enough. It should be as per the Swiss cheese theory where multiple things should fail before there's a problem. Further, not hide things like MCAS, downplay the need for additional training, refuse additional training when requested, change MCAS without notifying FAA, pressure people into being quick over safe, design MCAS to rely on a sensor, have a critical system (MCAS) rely on one sensor despite this not being allowed (critical systems MUST have multiple sensor inputs), etc. But yeah, it was the pilots not reading a message. Looking back, MCAS was not a good idea. But whatever led up to MCAS might have given the 737 MAX also some other bad changes. At the moment we don't know, maybe in future it'll be "obviously aside from MCAS the 737 MAX should also have a fix for X".
- WalterBright 6y ago
  > A crash is not due to one cause. Multiple things have to fail for this to be a problem. You're entirely correct. > Blaming pilots is way too simplistic. Also correct, but in my opinion the pilots were one of the multiple causes of the accidents, based on the published accounts of their actions. Ignoring Emergency Airworthiness Directives is inexcusable. Ignoring EADs is a problem that should be dealt with as part of the corrective actions required by the FAA. Recall that immediately prior to the LA crash, the previous flight crew on the same airplane had the same problem, dealt with it, and landed safely. (That was also before the EAD was issued.) Let me put it another way - would you want to get on an airplane with a crew that didn't pay attention to Emergency Airworthiness Directives? I wouldn't. And yes, Boeing must fix the MCAS system. I'm not excusing Boeing's role in the accidents.
- acqq 6y ago
  > it was the pilots not reading a message. It was that the message (see the whole, the link was quoted) definitely wasn't clear. It has multiple weasel words and it is far from a clear and actionable sequence checklist for the exact condition in which two planes were put due to the MCAS. Only with the hindsight of knowing how two accidents developed and the independent pilots trying to reconstruct on the simulators these events it can be claimed that that formulation described something usable. Just with the pilots "reading it" at that time and even having it in front of them at the moment of the accident, without any special training for that situation (where the plane multiple times "undoes" the actions of the pilot, orienting the plane toward ground as the plane is still flying low) it's still improbable that the accident wouldn't happen. Note: It's Boeing who insisted that the training for MCAS is not needed.
  - WalterBright 6y ago
    It's written in airplane jargon, of course, but it's plenty clear. > It's Boeing who insisted that the training for MCAS is not needed. It's not completely unreasonable to expect the pilots to be able to handle runaway trim, especially given an EMERGENCY AIRWORTHINESS DIRECTIVE reiterating how to do it. Runaway trim is a critical problem, which is why the electric trim switches are there as well as the cutoff switches, all in easy reach. Dealing with this is supposed to be a "memory item", meaning something the pilots must know. But clearly in hindsight, dealing with runaway trim must be specifically and better trained for. > special training The thing about runaway trim is it turns on when it's not supposed to. That's why the electric trim overrides are there and the cutoff switches. Those are there for all Boeing jets since electric trim was installed going back to at least 1960 and probably much earlier. When I worked on the stabilizer trim system on the 757, I worked mostly on the gearbox, but was peripherally involved with the electrical system for it. The cutoff switches were there for "when demons possess the control system and try to drive you into the ground."