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In the likely event that this is another MCAS related crash, I see only two possible reasons: 1. Boeing's suggested process (including flipping the two trim sw

In the likely event that this is another MCAS related crash, I see only two possible reasons: 1. Boeing's suggested process (including flipping the two trim switches and spinning a wheel) does not work for some reason. -or- 2. The Ethiopian pilots did not follow this process. I see #1 as putting a huge, huge amount of blame on Boeing and the FAA - especially given their months of "safe plane" reaction after Lion Air and their cavalier few days after Ethopian. I see #2 as still keeping a good deal of blame on Boeing, but also adding a significant training+capability element to Ethiopian and the pilots. Since Lion Air, how much had Boeing done to specify that the 737-MAX and the 737-NG are not the same plane and require different things to be aware of? Could a 737-MAX pilot really not have run through in their head a thousand times what MCAS related issues look like and what they would do if they started having those issues?

leggomylibro 8y ago
I was thinking about what you call '#2' the other day, when a family member remarked that the FAA was right to keep the planes in the sky because US airline unions felt like their pilots had received adequate advice and information from Boeing. I'm not sure where they got that from, but why would it be okay if the US pilots got training immediately, while others had to wait?
- crowdpleaser 8y ago
  It would be extremely irregular for an aviation company to give training / instruction to exclusive clubs. The reality is that occident pilots tend to be a cut above the rest of the world. American Airline pilots tend to have military aviation experience and/or thousands of hours of experience. Pilots in less developed nations tend to have significantly less training, I heard the copilot of the lion air flight only had a few hundred hours of experience.
  - cjbprime 8y ago
    But the pilot in the latest crash had been flying for Ethiopian for a decade, and Ethiopian's reputation for safety is excellent.
  - kniub 8y ago
    The copilot had 5000 flights hours. Bhavye Suneja, the pilot - Suneja had logged more than 6,000 flight hours, according to Lion Air. His co-pilot, whose name was Harvino - Harvino had logged more than 5,000 flight hours, according to Lion Air, which named him alongside Suneja. https://www.businessinsider.com.au/lion-air-plane-crash-victims-indonesia-2018-10?r=UK https://www.businessinsider.com.au/lion-air-plane-crash-vict...
    - deleted 8y ago
      [deleted]
    - acqq 8y ago
      To have some idea about the possible time span, we can estimate some "typical" flight frequency and length: if the average flight is 2.5 hours there, and if the pilot flights both to the destination and back in the same day (which is reasonable to expect) 6000 hours means 1200 flights to the destination and back, and if only one such is done per day (with the times on the ground it's surely more than 8 hours) then assuming 4 of such per week and 48 working weeks per year, that gives 6.5 years for the pilot and 5.2 years for the co-pilot.
  - inferiorhuman 8y ago
    Pilots in less developed nations tend to have significantly less training And yet at least one previous Lion Air crew had a run-in with MCAS and survived.
    - isostatic 8y ago
      And 83% of people playing russian roulette survive. Saying that some crews in some circumstances coped with the problem therefore all crews in all circumstances should be able to is disingenuous
  - tapland 8y ago
    The problem is mostly regulations allowing co-pilots to join in with extremely little experience. That was not the case here.
    - inferiorhuman 8y ago
      https://www.faa.gov/news/press_releases/news_story.cfm?newsId=14838 https://www.faa.gov/news/press_releases/news_story.cfm?newsI... Up until five or so years ago the FAA only mandated 250 hours of flight time to obtain an airline transport pilot license. Has American aviation gotten that much safer since then?
- isostatic 8y ago
  > because US airline unions felt like their pilots had received adequate advice and information from Boeing. And ET pilots felt they had received adequate advice and information from Boeing. > I'm not sure where they got that from, but why would it be okay if the US pilots got training immediately, while others had to wait? Something like https://www.forbes.com/sites/tedreed/2019/03/13/who-says-the-boeing-737max-is-safe-every-u-s-pilot-who-flies-it-says-so/amp/ https://www.forbes.com/sites/tedreed/2019/03/13/who-says-the... How that statement meshes with https://www.philly.com/business/boeing-max-pilots-complained-suspected-safety-flaw-20190312.html https://www.philly.com/business/boeing-max-pilots-complained... "Pilots repeatedly voiced safety concerns about the Boeing 737 Max 8 to federal authorities, with one captain calling the flight manual “inadequate and almost criminally insufficient” And "U.S. regulators are mandating that Boeing upgrade the plane’s software by April" is unclear. Back in 2016 it seems that the pilots union felt the MAX was a different plane: > hhttps://www.geekwire.com/2016/boeings-737-max-southwest-airlines-labor-dispute-pilots/ https://www.geekwire.com/2016/boeings-737-max-southwest-airl...
cjbprime 8y ago
I think both end up with blame on Boeing. If a discussion in world news isn't enough to prepare an experienced 737 pilot (ten years!) to counteract spurious MCAS, then nothing is, at least to the level of safety expected in airline travel. A plausible explanation for (1) that I've seen discussed is that, after disabling the auto trim, it may be impossible to manually re-trim while the yoke's pulled back, without first relieving aerodynamic stress on the elevator -- in this case by pointing the nose even farther down temporarily, which no sane pilot is going to want to do close to the ground. (I don't know whether it could actually happen this way.)
- honestoHeminway 8y ago
  So basically the auto-trim gets the plane into a impossible to recover from position at start? Seems plausible.
- VBprogrammer 8y ago
  I think it's unlikely that this crash will be attributed to the same set of circumstances as the lion air crash. I don't find it credible that an experienced pilot would fail to catch what, in essence, is a trim runaway event. There is a reason trim runaway is a memory item on almost all aircraft. Even in the Lion air case the previous flight experienced difficulty with the system and dealt with it. This was before the publication and a great deal of publicity of the details around MCAS. I don't think we've heard anything yet to suggest this particular aircraft had a fault in previous flights. Another failure in the AoA sensor on a brand new aircraft seems unlikely. I don't find 1 particularly compelling, it would have been noted by now if it was impossible to trim the aircraft using the manual trim wheels. Unless this is very specific to the MAX. That said, I think it's entirely possible there is something else wrong in the control of the MAX.
  - mattmcknight 8y ago
    >Another failure in the AoA sensor on a brand new aircraft seems unlikely. From another perspective, having one new sensor fail would seem to suggest that one should increase the prior probability for failure.
raverbashing 8y ago
1 can only be done after the problem is detected, which by then your plane is pointing dangerously down This happens in a critical time of flight, when pilots are busy with other tasks and are at a low altitude (less time to fix any problems). So no, Boeing's process is not a good solution.
- mannykannot 8y ago
  > 1 can only be done after the problem is detected, which by then your plane is pointing dangerously down. If you are referring to the documented procedure for recovering from a trim runaway, then all 737s would be dangerous, as this is the same procedure for trim runaway recovery as it is for the prior versions, and regardless of whether it is caused by an MCAS fault or for any other reason. The pilot is not expected to determine whether it is an MCAS fault before acting, because the recovery from runaway trim is the same, regardless of cause.
ulfw 8y ago
There is always option 3. Delay in processing of information and conflict resolution. It is possible the captains took to long to understand what is wrong, training or not and do the appropriate maneuvers to get the plane under control again. Option 3 happening at 40,000 feet has a very much better chance of a positive outcome than at 4,000 feet
LoSboccacc 8y ago
https://en.wikipedia.org/wiki/Lauda_Air_Flight_004#Previous_testing_of_thrust_reversers https://en.wikipedia.org/wiki/Lauda_Air_Flight_004#Previous_... > 1. Boeing's suggested process so I just happened to see the dramatization of this crash yesterday, and here boeing suggestion for a thrust reversal engaging in flight was likewise simple: cut throttle and fuel to engines. that was based under specific assumption of limited testing, while in the crash the pilot had 6 seconds between the engagement and total irrecoverable loss of control. > -or- assuming that just because there's a process the plane is safe is somewhat disingenuous, as it is placing the blame as an 'either/or' preposition. it might be that training is insufficient, but pilots don't control the training material. and following a checklist is somewhat hard if the plane constantly pulls down.
matwood 8y ago
> I see #2 as still keeping a good deal of blame on Boeing, Agreed. When users of my software fail to use the software properly some large part of the blame is still on me.
mannykannot 8y ago
I think there is a certain amount of hindsight in your response to scenario 1. While there is a good case to be made that Boeing was wrong to minimize the differences between the latest models and their predecessors, the Lion Air crash investigation did not produce any evidence that an MCAS fault could not be remedied by following the published procedure, and as far as I can tell, no other incidents prior to the Ethiopian Airlines crash have suggested that that, either. Up until possibly this crash, there has been no evidence that an MCAS fault presents any more risk, with a properly informed pilot at the controls, than would a trim runaway in the prior models. That is considered to be an acceptable risk, and the issue with properly informing pilots seemed to have been addressed. They should have reacted faster after the latest crash, but fortunately this delay has had no consequences. One would hope that the question of MCAS not being triply redundant will be reassessed, but the argument that it could do no more harm than a fault in the existing trim mechanism is not an unreasonable one, again if considered without hindsight.
- VBprogrammer 8y ago
  Perhaps it's just because I've been trying in vain to make similar points but I don't understand why you've been down voted here. It seems the only acceptable response is that Boeing deliberately killed people by trying to subvert the certification requirements and/or failing to inform pilots of a new system.
  - mannykannot 8y ago
    I am wondering why, if it was obvious that the 737 MAX should be grounded after the Lion Air crash, no one seemed to be saying that until the Ethiopian Airlines crash?

leggomylibro 8y ago

I was thinking about what you call '#2' the other day, when a family member remarked that the FAA was right to keep the planes in the sky because US airline unions felt like their pilots had received adequate advice and information from Boeing. I'm not sure where they got that from, but why would it be okay if the US pilots got training immediately, while others had to wait?

crowdpleaser 8y ago
It would be extremely irregular for an aviation company to give training / instruction to exclusive clubs. The reality is that occident pilots tend to be a cut above the rest of the world. American Airline pilots tend to have military aviation experience and/or thousands of hours of experience. Pilots in less developed nations tend to have significantly less training, I heard the copilot of the lion air flight only had a few hundred hours of experience.
- cjbprime 8y ago
  But the pilot in the latest crash had been flying for Ethiopian for a decade, and Ethiopian's reputation for safety is excellent.
- kniub 8y ago
  The copilot had 5000 flights hours. Bhavye Suneja, the pilot - Suneja had logged more than 6,000 flight hours, according to Lion Air. His co-pilot, whose name was Harvino - Harvino had logged more than 5,000 flight hours, according to Lion Air, which named him alongside Suneja. https://www.businessinsider.com.au/lion-air-plane-crash-victims-indonesia-2018-10?r=UK https://www.businessinsider.com.au/lion-air-plane-crash-vict...
  - deleted 8y ago
    [deleted]
  - acqq 8y ago
    To have some idea about the possible time span, we can estimate some "typical" flight frequency and length: if the average flight is 2.5 hours there, and if the pilot flights both to the destination and back in the same day (which is reasonable to expect) 6000 hours means 1200 flights to the destination and back, and if only one such is done per day (with the times on the ground it's surely more than 8 hours) then assuming 4 of such per week and 48 working weeks per year, that gives 6.5 years for the pilot and 5.2 years for the co-pilot.
- inferiorhuman 8y ago
  Pilots in less developed nations tend to have significantly less training And yet at least one previous Lion Air crew had a run-in with MCAS and survived.
  - isostatic 8y ago
    And 83% of people playing russian roulette survive. Saying that some crews in some circumstances coped with the problem therefore all crews in all circumstances should be able to is disingenuous
- tapland 8y ago
  The problem is mostly regulations allowing co-pilots to join in with extremely little experience. That was not the case here.
  - inferiorhuman 8y ago
    https://www.faa.gov/news/press_releases/news_story.cfm?newsId=14838 https://www.faa.gov/news/press_releases/news_story.cfm?newsI... Up until five or so years ago the FAA only mandated 250 hours of flight time to obtain an airline transport pilot license. Has American aviation gotten that much safer since then?
isostatic 8y ago
> because US airline unions felt like their pilots had received adequate advice and information from Boeing. And ET pilots felt they had received adequate advice and information from Boeing. > I'm not sure where they got that from, but why would it be okay if the US pilots got training immediately, while others had to wait? Something like https://www.forbes.com/sites/tedreed/2019/03/13/who-says-the-boeing-737max-is-safe-every-u-s-pilot-who-flies-it-says-so/amp/ https://www.forbes.com/sites/tedreed/2019/03/13/who-says-the... How that statement meshes with https://www.philly.com/business/boeing-max-pilots-complained-suspected-safety-flaw-20190312.html https://www.philly.com/business/boeing-max-pilots-complained... "Pilots repeatedly voiced safety concerns about the Boeing 737 Max 8 to federal authorities, with one captain calling the flight manual “inadequate and almost criminally insufficient” And "U.S. regulators are mandating that Boeing upgrade the plane’s software by April" is unclear. Back in 2016 it seems that the pilots union felt the MAX was a different plane: > hhttps://www.geekwire.com/2016/boeings-737-max-southwest-airlines-labor-dispute-pilots/ https://www.geekwire.com/2016/boeings-737-max-southwest-airl...

cjbprime 8y ago

I think both end up with blame on Boeing. If a discussion in world news isn't enough to prepare an experienced 737 pilot (ten years!) to counteract spurious MCAS, then nothing is, at least to the level of safety expected in airline travel. A plausible explanation for (1) that I've seen discussed is that, after disabling the auto trim, it may be impossible to manually re-trim while the yoke's pulled back, without first relieving aerodynamic stress on the elevator -- in this case by pointing the nose even farther down temporarily, which no sane pilot is going to want to do close to the ground. (I don't know whether it could actually happen this way.)

honestoHeminway 8y ago
So basically the auto-trim gets the plane into a impossible to recover from position at start? Seems plausible.
VBprogrammer 8y ago
I think it's unlikely that this crash will be attributed to the same set of circumstances as the lion air crash. I don't find it credible that an experienced pilot would fail to catch what, in essence, is a trim runaway event. There is a reason trim runaway is a memory item on almost all aircraft. Even in the Lion air case the previous flight experienced difficulty with the system and dealt with it. This was before the publication and a great deal of publicity of the details around MCAS. I don't think we've heard anything yet to suggest this particular aircraft had a fault in previous flights. Another failure in the AoA sensor on a brand new aircraft seems unlikely. I don't find 1 particularly compelling, it would have been noted by now if it was impossible to trim the aircraft using the manual trim wheels. Unless this is very specific to the MAX. That said, I think it's entirely possible there is something else wrong in the control of the MAX.
- mattmcknight 8y ago
  >Another failure in the AoA sensor on a brand new aircraft seems unlikely. From another perspective, having one new sensor fail would seem to suggest that one should increase the prior probability for failure.

raverbashing 8y ago

1 can only be done after the problem is detected, which by then your plane is pointing dangerously down This happens in a critical time of flight, when pilots are busy with other tasks and are at a low altitude (less time to fix any problems). So no, Boeing's process is not a good solution.

mannykannot 8y ago
> 1 can only be done after the problem is detected, which by then your plane is pointing dangerously down. If you are referring to the documented procedure for recovering from a trim runaway, then all 737s would be dangerous, as this is the same procedure for trim runaway recovery as it is for the prior versions, and regardless of whether it is caused by an MCAS fault or for any other reason. The pilot is not expected to determine whether it is an MCAS fault before acting, because the recovery from runaway trim is the same, regardless of cause.

ulfw 8y ago

There is always option 3. Delay in processing of information and conflict resolution. It is possible the captains took to long to understand what is wrong, training or not and do the appropriate maneuvers to get the plane under control again. Option 3 happening at 40,000 feet has a very much better chance of a positive outcome than at 4,000 feet

LoSboccacc 8y ago

https://en.wikipedia.org/wiki/Lauda_Air_Flight_004#Previous_testing_of_thrust_reversers https://en.wikipedia.org/wiki/Lauda_Air_Flight_004#Previous_... > 1. Boeing's suggested process so I just happened to see the dramatization of this crash yesterday, and here boeing suggestion for a thrust reversal engaging in flight was likewise simple: cut throttle and fuel to engines. that was based under specific assumption of limited testing, while in the crash the pilot had 6 seconds between the engagement and total irrecoverable loss of control. > -or- assuming that just because there's a process the plane is safe is somewhat disingenuous, as it is placing the blame as an 'either/or' preposition. it might be that training is insufficient, but pilots don't control the training material. and following a checklist is somewhat hard if the plane constantly pulls down.

matwood 8y ago

> I see #2 as still keeping a good deal of blame on Boeing, Agreed. When users of my software fail to use the software properly some large part of the blame is still on me.

mannykannot 8y ago

I think there is a certain amount of hindsight in your response to scenario 1. While there is a good case to be made that Boeing was wrong to minimize the differences between the latest models and their predecessors, the Lion Air crash investigation did not produce any evidence that an MCAS fault could not be remedied by following the published procedure, and as far as I can tell, no other incidents prior to the Ethiopian Airlines crash have suggested that that, either. Up until possibly this crash, there has been no evidence that an MCAS fault presents any more risk, with a properly informed pilot at the controls, than would a trim runaway in the prior models. That is considered to be an acceptable risk, and the issue with properly informing pilots seemed to have been addressed. They should have reacted faster after the latest crash, but fortunately this delay has had no consequences. One would hope that the question of MCAS not being triply redundant will be reassessed, but the argument that it could do no more harm than a fault in the existing trim mechanism is not an unreasonable one, again if considered without hindsight.

VBprogrammer 8y ago
Perhaps it's just because I've been trying in vain to make similar points but I don't understand why you've been down voted here. It seems the only acceptable response is that Boeing deliberately killed people by trying to subvert the certification requirements and/or failing to inform pilots of a new system.
- mannykannot 8y ago
  I am wondering why, if it was obvious that the 737 MAX should be grounded after the Lion Air crash, no one seemed to be saying that until the Ethiopian Airlines crash?