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Main stream media made it sound like 40 seconds is way too short of a time to troubleshoot the issue. But now that you state it that way, I gotta agree with you

Main stream media made it sound like 40 seconds is way too short of a time to troubleshoot the issue. But now that you state it that way, I gotta agree with you it's not Only Boeings fault. Sure they are big significant part of the issue. But not the only part.

chopin 8y ago
40s is only enough if you know what to do right away from the start of the situation. A failing sensor may confront the pilots with many (unrelated to a trim runaway) warnings (like unreliable airspeed, stick shaker, alt disagree). That has been the case for Lion Air at least.
- sokoloff 8y ago
  Take a car analogy. Suppose your car starts drifting into oncoming traffic. Maybe the road crown changed, maybe your alignment changed from a debris strike, maybe you have a tire going down, maybe you have a crosswind. In all those cases, your reaction is the same and instinctive regardless of whether or not you know the root cause. Flying an airplane manually on instruments, the pilot sees the airplane undershooting the pitch target and pulls back on the control column every bit as naturally as the car driver above. When the pitch target is correct and the control force high, use the stab trim to take the force away. This is every bit as much a continual process as the driver lane keeping. If MCAS is trimming against you every time you let go of the trim, you get feedback that this is likely a trim issue. Keep flying the airplane and trimming as needed. This is not a case where the airplane automation fails and an airplane suddenly gets “dumped” onto a pilot who has to regain control and figure things out. It’s obvious that the time and space available was not enough for that Lion Air or that Ethiopian Air flight, so you have real world evidence to support your point. I acknowledge that fact, of course.
karlkatzke 8y ago
As someone who's done a bunch of human factors design training for critical situations in a previous career as a UI/UX designer and now works as a systems engineer doing a bunch of alerting, 40 seconds is too short of a time to troubleshoot the issue. When this situation happens, five things happen at once. MASTER CAUTION (whoop, whoop noises and a big red light!), ALT DISAGREE alert on the MFD, Incorrect Airspeed on the MFD, the stick shaker goes off, and by the way, if you take the time to look down at the throttle section of the dashboard with all those other alerts going off, you'd see that there is suddenly a lot of trim on the APL trim indicator but the trim wheel doesn't actually move (which would provide an audible 'click click click' that would probably trigger that there was a problem with trim. Each of those things has a separate memory checklist that you have to run down, and subtract ten seconds to register them, prioritize, communicate with the other pilot, and start executing them. The worst part here is that they've added another alert and then changed how the airplane will fly in the middle of an emergency. While the extra alert narrows down the number of branches from the "prioritization" part of the checklist, I'm not sure that's "fixing" the problem.
- ams6110 8y ago
  The trim wheel always moves on the 737. It's physically connected to the stabilizer. If the stabilizer is moving, the trim wheel is moving. Otherwise, yes I agree. A lot of stuff probably went crazy in a short time for them.
- VBprogrammer 8y ago
  The fix for the problem is that it can no longer repeatedly drive the trim to it's extremes. There should be plenty of elevator authority counter a single trim movement of 2.5 units. I appreciate your point about all of the alerts going off however the pilot is manually flying the aircraft at this point, they should feel that something is going on through the controls and react to that firstly. Imagine having a blow-out in a fancy car with pressure sensors, sure lots of alerts are going off but you have probably not registered that because keeping the car going in a straight line is taking 100% of your attention.
  - ams6110 8y ago
    Good point, and that's why there are two pilots. When stuff goes crazy, one flies the plane, the other one runs the checklists.

chopin 8y ago

40s is only enough if you know what to do right away from the start of the situation. A failing sensor may confront the pilots with many (unrelated to a trim runaway) warnings (like unreliable airspeed, stick shaker, alt disagree). That has been the case for Lion Air at least.

sokoloff 8y ago
Take a car analogy. Suppose your car starts drifting into oncoming traffic. Maybe the road crown changed, maybe your alignment changed from a debris strike, maybe you have a tire going down, maybe you have a crosswind. In all those cases, your reaction is the same and instinctive regardless of whether or not you know the root cause. Flying an airplane manually on instruments, the pilot sees the airplane undershooting the pitch target and pulls back on the control column every bit as naturally as the car driver above. When the pitch target is correct and the control force high, use the stab trim to take the force away. This is every bit as much a continual process as the driver lane keeping. If MCAS is trimming against you every time you let go of the trim, you get feedback that this is likely a trim issue. Keep flying the airplane and trimming as needed. This is not a case where the airplane automation fails and an airplane suddenly gets “dumped” onto a pilot who has to regain control and figure things out. It’s obvious that the time and space available was not enough for that Lion Air or that Ethiopian Air flight, so you have real world evidence to support your point. I acknowledge that fact, of course.

karlkatzke 8y ago

As someone who's done a bunch of human factors design training for critical situations in a previous career as a UI/UX designer and now works as a systems engineer doing a bunch of alerting, 40 seconds is too short of a time to troubleshoot the issue. When this situation happens, five things happen at once. MASTER CAUTION (whoop, whoop noises and a big red light!), ALT DISAGREE alert on the MFD, Incorrect Airspeed on the MFD, the stick shaker goes off, and by the way, if you take the time to look down at the throttle section of the dashboard with all those other alerts going off, you'd see that there is suddenly a lot of trim on the APL trim indicator but the trim wheel doesn't actually move (which would provide an audible 'click click click' that would probably trigger that there was a problem with trim. Each of those things has a separate memory checklist that you have to run down, and subtract ten seconds to register them, prioritize, communicate with the other pilot, and start executing them. The worst part here is that they've added another alert and then changed how the airplane will fly in the middle of an emergency. While the extra alert narrows down the number of branches from the "prioritization" part of the checklist, I'm not sure that's "fixing" the problem.

ams6110 8y ago
The trim wheel always moves on the 737. It's physically connected to the stabilizer. If the stabilizer is moving, the trim wheel is moving. Otherwise, yes I agree. A lot of stuff probably went crazy in a short time for them.
VBprogrammer 8y ago
The fix for the problem is that it can no longer repeatedly drive the trim to it's extremes. There should be plenty of elevator authority counter a single trim movement of 2.5 units. I appreciate your point about all of the alerts going off however the pilot is manually flying the aircraft at this point, they should feel that something is going on through the controls and react to that firstly. Imagine having a blow-out in a fancy car with pressure sensors, sure lots of alerts are going off but you have probably not registered that because keeping the car going in a straight line is taking 100% of your attention.
- ams6110 8y ago
  Good point, and that's why there are two pilots. When stuff goes crazy, one flies the plane, the other one runs the checklists.