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I have no expertise in the area, but I doubt it's the same cause. Every 737 Max pilot will certainly be aware of the Lion Air crash and the ways to mitigate tha

I have no expertise in the area, but I doubt it's the same cause. Every 737 Max pilot will certainly be aware of the Lion Air crash and the ways to mitigate that particular behavior of the aircraft. We need to wait for the investigation before we jump to conclusions.

woodandsteel 8y ago
>Every 737 Max pilot will certainly be aware of the Lion Air crash and the ways to mitigate that particular behavior of the aircraft. I think that is a good point.
deleted 8y ago
[deleted]
nostromo 8y ago
Not necessarily. The 737 Max is the same type rating as all other 737. That means the pilots and crew switch back and forth between the Max and non-Max planes — despite the fact that they act very different in certain circumstances. This was intentional, it saves airlines money to have fewer type ratings. Besides, so soon after take off there’s very little time to recover when your plane is overriding you attempts to keep it from nose diving into the ground. It’s not as simple as flipping a single switch.
- neuronic 8y ago
  Why arent pilots able to take full and absolute control of a plane at any time whatsoever?
  - ThenAsNow 8y ago
    What does "full and absolute control" mean in the context of a fly-by-wire aircraft? AA587 is blamed on a pilot's inputs driving a structural capability exceedance in the vertical stabilizer. For reasons such as these, all fly-by-wire aircraft will have some measure of envelope protection whereby pilot inputs projected to exceed aircraft capability will be limited. There is always "interpretation" of pilot inputs involved in fly-by-wire systems. The key is in making available all control power to the pilot that will not result in catastrophic structural failure of the aircraft. And the associated challenges are knowing exactly where those boundaries should be set in the design of the control system, as well as the knowledge of the aircraft state to the flight computers.
    - neuronic 8y ago
      Thank you for the extensive response. With that context, I would say "full control" should amount to the ability of a pilot to overrule systems that may send an aircraft nosediving due to faulty sensors. Did the pilots of the Lion Air flight and possibly the Ethiopian Air flight understand what was wrong in-flight and were unable to fix it due to an inability to override aircraft controls? This is what I am getting out of the discussion so far but maybe I am gravely misunderstanding what's happening? So as a passenger without any knowledge of aviation systems my question is merely whether the pilot gets control over the aircraft when he demands it? Fly-by-wire should at least never lead to autopilot suicide, even if it has to ensure flight integrity to a certain degree due to the technical nature of large, modern aircraft.
      - m0llusk 8y ago
        We demand this level of conscious awareness and control of 4-5 year old children in our society but machines that carry dozens of lives are not held to such a standard of attention and interaction. This might be something that AI can address, but most current offerings still lack features we consider essential for even very young children.
      - ThenAsNow 8y ago
        > Thank you for the extensive response. With that context, I would say "full control" should amount to the ability of a pilot to overrule systems that may send an aircraft nosediving due to faulty sensors. Thanks for reading it :) . As you phrased it specifically, I can't disagree with you. But in these systems, the devil is in the details. For Boeing's MCAS, which is like an add-on piece of functionality to the core control system, it seems like an obvious piece which should have a manual override - and it does. The criticism, as I understand it based on Lion Air, is that the override functionality is not obvious and if you were previously a 737 pilot on non-Max variants, you might not know about this or have practiced its use. However, consider safety systems such as Automatic Ground Collision Avoidance System ("Auto GCAS") or Automatic Air Collision Avoidance System ("Auto ACAS"). These systems are designed as reactions to multiple known cases of human error that have resulted in otherwise under-control aircraft being flown into the ground or other aircraft. They are specifically designed to override a mistaken human. Technically, it's not impossible that pathological failures or spoofing could trigger these automated systems, which would wrest control away from pilots. Should such systems be overridable at all times? Resolving these kinds of issues does involve some judgment and adopting a philosophy prior to the implementation. Airbus and Boeing, for example, have historically differed in their philosophies, each with reasonable rationale. I personally favor the approach Boeing has historically used, with AF447 and QF32 illustrating some of the pitfalls of Airbus' approach. For example, as pointed out by ggreer in https://news.ycombinator.com/item?id=19355402 https://news.ycombinator.com/item?id=19355402 , being susceptible to common mode faults. However, I still fly on either manufacturer's aircraft without hesitation.
- A2017U1 8y ago
  > It’s not as simple as flipping a single switch. Except that's exactly what it is and then manually setting the trim. The NY times had an excellent article about the procedure: > The crucial step, would be to reach across to the central console to a pair of switches, and flip the switches off. Those switches disable electric control of the motor that moves the stabilizers up and down, preventing the anti-stall system from exerting control over their position. https://www.nytimes.com/interactive/2018/11/16/world/asia/lion-air-crash-cockpit.html https://www.nytimes.com/interactive/2018/11/16/world/asia/li...
  - kcmastrpc 8y ago
    If you're used to flying a plane for several thousand hours that's not going to be second nature at all (when the procedure has changed). You really should watch this video just to get an idea of how catastrophic this error is: https://youtu.be/baK39CrgW-4?t=363 https://youtu.be/baK39CrgW-4?t=363
    - A2017U1 8y ago
      Not sure what I'm meant to glean from that video? It's the last 10 seconds of the flight? The lion air pilots had 15 mins to disable the automatic trim system and simply set the trim manually. It's turning off a switch and spinning a wheel. Manually setting trim is second nature to student pilots. They should also have read the log prior to departure and seen the previous four flights had this problem that did exactly this. Quite sure pilot error will be the outcome for lion air. There's absolutely no difference in procedure here a normal 737. Unsure where you got that idea from.
      - kcmastrpc 8y ago
        Perhaps how catastrophic this issue could be while the flight is still in low altitude during one of the busiest phases of operations? The procedure to set the trim manually was the same, but I assume that in most flights the actual flywheel is never turned by hand (and thus rarely deactivated). I'm sure most pilots use the fly-by-wire systems or autopilot. The procedure which was different was the automated MCAS system - pilots who have logged significant hours flying the previous model of 737 would be unprepared for this during an extremely busy phase of the flight. Ultimately, yes, it was the pilots error when they didn't take the proper actions when the problem first occurred. Nevertheless, we must first take into account why the automated system failed to begin with, and why the pilots made the error (lack of training, sleep, preparation). This isn't binary, and the fact Boeing is issuing a patch for the software systems as a direct result of Lion Air tells me there is more to the story than just "pilot error".
avs733 8y ago
That's like suggesting that once a patch exists for a vulnerability in software that tye vulnerability no longer exists. Dissemination of information about a risk is an entirely separate issue from creating a solution to the underlying flaw.
dclowd9901 8y ago
Nope. We ground the planes until we figure out what’s wrong. There is simply too much risk in “not jumping to conclusions,” unless you wouldn’t mind the deaths of a couple hundred people on your head?

woodandsteel 8y ago

>Every 737 Max pilot will certainly be aware of the Lion Air crash and the ways to mitigate that particular behavior of the aircraft. I think that is a good point.

deleted 8y ago

[deleted]

nostromo 8y ago

Not necessarily. The 737 Max is the same type rating as all other 737. That means the pilots and crew switch back and forth between the Max and non-Max planes — despite the fact that they act very different in certain circumstances. This was intentional, it saves airlines money to have fewer type ratings. Besides, so soon after take off there’s very little time to recover when your plane is overriding you attempts to keep it from nose diving into the ground. It’s not as simple as flipping a single switch.

neuronic 8y ago
Why arent pilots able to take full and absolute control of a plane at any time whatsoever?
- ThenAsNow 8y ago
  What does "full and absolute control" mean in the context of a fly-by-wire aircraft? AA587 is blamed on a pilot's inputs driving a structural capability exceedance in the vertical stabilizer. For reasons such as these, all fly-by-wire aircraft will have some measure of envelope protection whereby pilot inputs projected to exceed aircraft capability will be limited. There is always "interpretation" of pilot inputs involved in fly-by-wire systems. The key is in making available all control power to the pilot that will not result in catastrophic structural failure of the aircraft. And the associated challenges are knowing exactly where those boundaries should be set in the design of the control system, as well as the knowledge of the aircraft state to the flight computers.
  - neuronic 8y ago
    Thank you for the extensive response. With that context, I would say "full control" should amount to the ability of a pilot to overrule systems that may send an aircraft nosediving due to faulty sensors. Did the pilots of the Lion Air flight and possibly the Ethiopian Air flight understand what was wrong in-flight and were unable to fix it due to an inability to override aircraft controls? This is what I am getting out of the discussion so far but maybe I am gravely misunderstanding what's happening? So as a passenger without any knowledge of aviation systems my question is merely whether the pilot gets control over the aircraft when he demands it? Fly-by-wire should at least never lead to autopilot suicide, even if it has to ensure flight integrity to a certain degree due to the technical nature of large, modern aircraft.
    - m0llusk 8y ago
      We demand this level of conscious awareness and control of 4-5 year old children in our society but machines that carry dozens of lives are not held to such a standard of attention and interaction. This might be something that AI can address, but most current offerings still lack features we consider essential for even very young children.
    - ThenAsNow 8y ago
      > Thank you for the extensive response. With that context, I would say "full control" should amount to the ability of a pilot to overrule systems that may send an aircraft nosediving due to faulty sensors. Thanks for reading it :) . As you phrased it specifically, I can't disagree with you. But in these systems, the devil is in the details. For Boeing's MCAS, which is like an add-on piece of functionality to the core control system, it seems like an obvious piece which should have a manual override - and it does. The criticism, as I understand it based on Lion Air, is that the override functionality is not obvious and if you were previously a 737 pilot on non-Max variants, you might not know about this or have practiced its use. However, consider safety systems such as Automatic Ground Collision Avoidance System ("Auto GCAS") or Automatic Air Collision Avoidance System ("Auto ACAS"). These systems are designed as reactions to multiple known cases of human error that have resulted in otherwise under-control aircraft being flown into the ground or other aircraft. They are specifically designed to override a mistaken human. Technically, it's not impossible that pathological failures or spoofing could trigger these automated systems, which would wrest control away from pilots. Should such systems be overridable at all times? Resolving these kinds of issues does involve some judgment and adopting a philosophy prior to the implementation. Airbus and Boeing, for example, have historically differed in their philosophies, each with reasonable rationale. I personally favor the approach Boeing has historically used, with AF447 and QF32 illustrating some of the pitfalls of Airbus' approach. For example, as pointed out by ggreer in https://news.ycombinator.com/item?id=19355402 https://news.ycombinator.com/item?id=19355402 , being susceptible to common mode faults. However, I still fly on either manufacturer's aircraft without hesitation.
A2017U1 8y ago
> It’s not as simple as flipping a single switch. Except that's exactly what it is and then manually setting the trim. The NY times had an excellent article about the procedure: > The crucial step, would be to reach across to the central console to a pair of switches, and flip the switches off. Those switches disable electric control of the motor that moves the stabilizers up and down, preventing the anti-stall system from exerting control over their position. https://www.nytimes.com/interactive/2018/11/16/world/asia/lion-air-crash-cockpit.html https://www.nytimes.com/interactive/2018/11/16/world/asia/li...
- kcmastrpc 8y ago
  If you're used to flying a plane for several thousand hours that's not going to be second nature at all (when the procedure has changed). You really should watch this video just to get an idea of how catastrophic this error is: https://youtu.be/baK39CrgW-4?t=363 https://youtu.be/baK39CrgW-4?t=363
  - A2017U1 8y ago
    Not sure what I'm meant to glean from that video? It's the last 10 seconds of the flight? The lion air pilots had 15 mins to disable the automatic trim system and simply set the trim manually. It's turning off a switch and spinning a wheel. Manually setting trim is second nature to student pilots. They should also have read the log prior to departure and seen the previous four flights had this problem that did exactly this. Quite sure pilot error will be the outcome for lion air. There's absolutely no difference in procedure here a normal 737. Unsure where you got that idea from.
    - kcmastrpc 8y ago
      Perhaps how catastrophic this issue could be while the flight is still in low altitude during one of the busiest phases of operations? The procedure to set the trim manually was the same, but I assume that in most flights the actual flywheel is never turned by hand (and thus rarely deactivated). I'm sure most pilots use the fly-by-wire systems or autopilot. The procedure which was different was the automated MCAS system - pilots who have logged significant hours flying the previous model of 737 would be unprepared for this during an extremely busy phase of the flight. Ultimately, yes, it was the pilots error when they didn't take the proper actions when the problem first occurred. Nevertheless, we must first take into account why the automated system failed to begin with, and why the pilots made the error (lack of training, sleep, preparation). This isn't binary, and the fact Boeing is issuing a patch for the software systems as a direct result of Lion Air tells me there is more to the story than just "pilot error".

avs733 8y ago

That's like suggesting that once a patch exists for a vulnerability in software that tye vulnerability no longer exists. Dissemination of information about a risk is an entirely separate issue from creating a solution to the underlying flaw.

dclowd9901 8y ago

Nope. We ground the planes until we figure out what’s wrong. There is simply too much risk in “not jumping to conclusions,” unless you wouldn’t mind the deaths of a couple hundred people on your head?