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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 wat

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".
  - A2017U1 8y ago
    Sensors fail all the time modern aircraft, people would probably be quite scared knowing how often. After the Airfrance airbus incident they also introduced a "patch" to protect the aircraft from erroneous pilot actions leading to stalls when indicators are incorrect, those fixes were certainly not indicative of guilt but just another layer to stop pilots making mistakes.
- inferiorhuman 8y ago
  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. To put it bluntly only a fool is going to start flipping switches willy nilly. Boeing has a procedure out to handle runaway stabilizer trim, and that's to flip the switches, but the Lion Air pilots did not encounter a runaway stabilizer so why would they go down that checklist and potentially add to their troubles? In the case of the cutout switches, those switches do different things on the NG and MAX (and are thus labeled differently) which potentially adds to the confusion and reduces the incentive to experiment. You're talking about counteracting a system that Boeing hid from pilots — hardly pilot error. In fact if you look at the FDR data you'll see that the pilots were able to temporarily disable MCAS with the trim buttons on the yoke. Every time MCAS trimmed down, the pilot trimmed up and was able to maintain appropriate trim. That worked, and it seemed like the plane was largely under control (until it wasn't). Meanwhile the unreliable airspeed indicators were illuminated and one of the stick shakers was going off, and there was probably an EICAS message about the elevator feel system but no actual indication of the underlying problem with AoA was given because Boeing charges extra for that. So, with the assumption that you had the stabilizer trim under control, why would you add to the significant workload by disabling the electrical control of the stabilizer?
  - A2017U1 8y ago
    > with the assumption that you had the stabilizer trim under control, why would you add to the significant workload by disabling the electrical control of the stabilizer? I'm struggling to see how you think having to make manual adjustments every 30 seconds is "under control". Check the flight profile, it was never under control. > the Lion Air pilots did not encounter a runaway stabilizer What did the pilots on the four previous flights encounter? Did they not follow procedure correctly by overriding it? The trim stabiliser had to be adjusted 23 times during the the fatal flight, this is a solid fact. After a few times it should have been very apparent that there was a problem related to the automatic trim system and switched to manual. Manual trim would only get adjusted a only few times during a regular flight, it's a very basic skill and the trim wheel itself takes up a huge amount of real estate in modern cockpits. Sorry but you've written a lot of terribly inaccurate stuff here. Let's see what the report says. There are dozens of design flaws in modern aircraft, a miniscule amount are unrecoverable following procedure. The process to manually override trim on a 737 that should have been followed: 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...

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".
- A2017U1 8y ago
  Sensors fail all the time modern aircraft, people would probably be quite scared knowing how often. After the Airfrance airbus incident they also introduced a "patch" to protect the aircraft from erroneous pilot actions leading to stalls when indicators are incorrect, those fixes were certainly not indicative of guilt but just another layer to stop pilots making mistakes.
inferiorhuman 8y ago
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. To put it bluntly only a fool is going to start flipping switches willy nilly. Boeing has a procedure out to handle runaway stabilizer trim, and that's to flip the switches, but the Lion Air pilots did not encounter a runaway stabilizer so why would they go down that checklist and potentially add to their troubles? In the case of the cutout switches, those switches do different things on the NG and MAX (and are thus labeled differently) which potentially adds to the confusion and reduces the incentive to experiment. You're talking about counteracting a system that Boeing hid from pilots — hardly pilot error. In fact if you look at the FDR data you'll see that the pilots were able to temporarily disable MCAS with the trim buttons on the yoke. Every time MCAS trimmed down, the pilot trimmed up and was able to maintain appropriate trim. That worked, and it seemed like the plane was largely under control (until it wasn't). Meanwhile the unreliable airspeed indicators were illuminated and one of the stick shakers was going off, and there was probably an EICAS message about the elevator feel system but no actual indication of the underlying problem with AoA was given because Boeing charges extra for that. So, with the assumption that you had the stabilizer trim under control, why would you add to the significant workload by disabling the electrical control of the stabilizer?
- A2017U1 8y ago
  > with the assumption that you had the stabilizer trim under control, why would you add to the significant workload by disabling the electrical control of the stabilizer? I'm struggling to see how you think having to make manual adjustments every 30 seconds is "under control". Check the flight profile, it was never under control. > the Lion Air pilots did not encounter a runaway stabilizer What did the pilots on the four previous flights encounter? Did they not follow procedure correctly by overriding it? The trim stabiliser had to be adjusted 23 times during the the fatal flight, this is a solid fact. After a few times it should have been very apparent that there was a problem related to the automatic trim system and switched to manual. Manual trim would only get adjusted a only few times during a regular flight, it's a very basic skill and the trim wheel itself takes up a huge amount of real estate in modern cockpits. Sorry but you've written a lot of terribly inaccurate stuff here. Let's see what the report says. There are dozens of design flaws in modern aircraft, a miniscule amount are unrecoverable following procedure. The process to manually override trim on a 737 that should have been followed: 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...