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This type of information is very convenient for Boeing... Edit: It's likely true, but surely nearly every airline had a pilot 'warn of dangers'. But why is thi

This type of information is very convenient for Boeing... Edit: It's likely true, but surely nearly every airline had a pilot 'warn of dangers'. But why is this a news story being promoted?

jamisteven 7y ago
Why is it convenient for Boeing?
- tomglynch 7y ago
  Boeing is trying to claim inadequate training (by the airlines) is the problem, not the fact the MCAS software bandaid had serious design flaws yet Boeing pushed for it in order to compete with Airbus.
  - bkor 7y ago
    If poor training was the cause the plane shouldn't have received the same type number. So this is all still on Boeing. Boeing also specifically told these planes with the benefit that only a few hours of training would be enough. I'm not seeing how this is beneficial for Boeing.
    - sambull 7y ago
      I'm starting to think a plane that can't glide during a emergency because they decided to deny physics is just not a good design.
      - _ph_ 7y ago
        The 737 can glide as fine as a plane of that size can. The MAX didn't change anything at that and no one was denying physics. The problem was the MCAS, which as a result of a single sensor malfunction would aggressively point the nose down via the stabilizer trim.
        tomglynch 7y ago
        Yep, the reason they implemented MCAS was because they popped on some larger engines, which were too close to the ground, so they moved them up and forward on the wing a bit. This gave the plane a tendency to tilt up which could cause a stall, so Boeing added some software to bring the nose down. In both crashes, one of the two Angle of Attack sensors was incorrect. Boeing only use one AoA sensor per flight (alternating for some bewildering reason), and in this particular flight it was constantly incorrectly stating the plane was nearing a stall. So MCAS would continually kick in until the Pilot could no longer keep the plane in the air.
        liability 7y ago
        > "This gave the plane a tendency to tilt up which could cause a stall" That tendency also exists on Classic and NG 737's, and is something pilots are trained to compensate for. The issue with the MAX is the degree of this tendency changed. MCAS was meant to emulate the old (less severe) behavior.
        scifi6546 7y ago
        Couldn't Boeing just put in a bunch of gyroscopes into the chassis and use that as a backup AoA sensor? (I am not a pilot so I have no clue if that is reasonable)
        ddalex 7y ago
        The plane attitude (what you can sense with gyros) and angle of attack are very different things. They only coincide in level flight with no wind (the attitude is measured to the earth frame of reference (transposed by gyros) and the AoA is measured with reference to the local wind stream)
        glenneroo 7y ago
        OK then why not put a couple extra AoA sensors in? I thought everything critical on airliners was supposedly redundant?
      - peteradio 7y ago
        That is not what is wrong with the plane.
      - groby_b 7y ago
        This has very little to do with the plane's ability to glide. (A 737 glides just fine, if a bit steep for my taste). In that particular emergency, the control surfaces prevent it from gliding. You can even have issues on a Cessna - loss of elevator is not fun.[1] It's not about "denying physics", it's about having insufficient redundancy[2] and improper amount of control from MCAS - 3 times more than the FAA approved: [3] No plane is 100% safe. Boeing made this one worse for the sake of saving money - the physics work out just fine, and gliding ability is not really impacted. (But I don't think it'd be a normal response - I can't imagine a pilot thinking "oh, I'm getting a stall warning with nose down at 4,000 feet, I know, I'll cut power and glide".) [1] https://airfactsjournal.com/2018/12/elevator-failure-at-4500-feet-in-a-cessna-150/ https://airfactsjournal.com/2018/12/elevator-failure-at-4500... [2] https://www.seattletimes.com/business/boeing-aerospace/a-lack-of-redundancies-on-737-max-system-has-baffled-even-those-who-worked-on-the-jet/ https://www.seattletimes.com/business/boeing-aerospace/a-lac... [3] https://www.seattletimes.com/business/boeing-aerospace/failed-certification-faa-missed-safety-issues-in-the-737-max-system-implicated-in-the-lion-air-crash/ https://www.seattletimes.com/business/boeing-aerospace/faile...
    - tomglynch 7y ago
      Boeing seem to be pushing part of the blame to the pilot's -"Pilot error" - but this isn't due to 'lack of training' but the fact there was NO training and MCAS was not included in the manuals [1][2]. [1] https://www.seattletimes.com/business/boeing-aerospace/u-s-pilots-flying-737-max-werent-told-about-new-automatic-systems-change-linked-to-lion-air-crash/ https://www.seattletimes.com/business/boeing-aerospace/u-s-p... > Jon Weaks, president of the Southwest Airlines Pilots Association, said Monday the airline and the pilots “were kept in the dark.” “We do not like the fact that a new system was put on the aircraft and wasn’t disclosed to anyone or put in the manuals,” he said in an interview. What’s more, he noted, Boeing and the Federal Aviation Administration have now warned “that the system may not be performing as it should.” [2] https://theaircurrent.com/aviation-safety/what-is-the-boeing-737-max-maneuvering-characteristics-augmentation-system-mcas-jt610/ https://theaircurrent.com/aviation-safety/what-is-the-boeing... > "Since it operates in situations where the aircraft is under relatively high g load and near stall, a pilot should never see the operation of MCAS. As such, Boeing did not include an MCAS description in its FCOM. The explainer continues: "In this case, MCAS will trim nose as designed to assist the pilot during recover, likely going unnoticed by the pilot." There is another explanation, according to a Tuesday report in The Wall Street Journal: "One high-ranking Boeing official said the company had decided against disclosing more details to cockpit crews due to concerns about inundating average pilots with too much information - and significantly more technical data - than they needed or could digest."
- hammock 7y ago
  Because it focuses blame on the airlines and pilots for executing poor judgment, and suggests that Boeing didn't create any risk that the downstream parties weren't aware of or in control of.
StreamBright 7y ago
In one it helps them, pushing the narrative that more training would have avoided the disaster, on the other hand this questions if MAX should have been approved by FAA as a 737 variant that does not require re-training.
- tomglynch 7y ago
  If I'm not mistaken, Boeing themselves were the auditor for this on behalf of the FAA.
  - tremon 7y ago
    It is both. FAA establishes guidelines for planes and designs to meet, and the airlines (not just Boeing) are responsible for certifying and rating their planes according to those guidelines. This is not simply a case of regulatory capture, the FAA simply doesn't have the expertise and in-depth knowledge to perform completely independent verification. Requiring the FAA to do so might be prohibitively expensive, so this arrangement is the result of pragmatic realism more than regulatory capture. It does require a great amount of trust between all partners though, and it seems to me Boeing has been more than happy to skirt their responsibility in this case.
    - dillonmckay 7y ago
      You say airlines, but I think you mean airplane manufacturers? Perhaps the airplane manufacturer and certifier should be separate manufacturers? How is the NHTSA able to certify crash tests for every make and model vehicle sold each year?
      - tomglynch 7y ago
        The FAA delegate much of the certification to Boeing [1], and to me it seems either the FAA is underfunded, or Boeing was in bed with the FAA to push things through quicker. [1] https://www.seattletimes.com/business/boeing-aerospace/failed-certification-faa-missed-safety-issues-in-the-737-max-system-implicated-in-the-lion-air-crash/ https://www.seattletimes.com/business/boeing-aerospace/faile...

This type of information is very convenient for Boeing... Edit: It's likely true, but surely nearly every airline had a pilot 'warn of dangers'. But why is this a news story being promoted?

jamisteven 7y ago

Why is it convenient for Boeing?

tomglynch 7y ago
Boeing is trying to claim inadequate training (by the airlines) is the problem, not the fact the MCAS software bandaid had serious design flaws yet Boeing pushed for it in order to compete with Airbus.
- bkor 7y ago
  If poor training was the cause the plane shouldn't have received the same type number. So this is all still on Boeing. Boeing also specifically told these planes with the benefit that only a few hours of training would be enough. I'm not seeing how this is beneficial for Boeing.
  - sambull 7y ago
    I'm starting to think a plane that can't glide during a emergency because they decided to deny physics is just not a good design.
    - _ph_ 7y ago
      The 737 can glide as fine as a plane of that size can. The MAX didn't change anything at that and no one was denying physics. The problem was the MCAS, which as a result of a single sensor malfunction would aggressively point the nose down via the stabilizer trim.
      - tomglynch 7y ago
        Yep, the reason they implemented MCAS was because they popped on some larger engines, which were too close to the ground, so they moved them up and forward on the wing a bit. This gave the plane a tendency to tilt up which could cause a stall, so Boeing added some software to bring the nose down. In both crashes, one of the two Angle of Attack sensors was incorrect. Boeing only use one AoA sensor per flight (alternating for some bewildering reason), and in this particular flight it was constantly incorrectly stating the plane was nearing a stall. So MCAS would continually kick in until the Pilot could no longer keep the plane in the air.
        liability 7y ago
        > "This gave the plane a tendency to tilt up which could cause a stall" That tendency also exists on Classic and NG 737's, and is something pilots are trained to compensate for. The issue with the MAX is the degree of this tendency changed. MCAS was meant to emulate the old (less severe) behavior.
        scifi6546 7y ago
        Couldn't Boeing just put in a bunch of gyroscopes into the chassis and use that as a backup AoA sensor? (I am not a pilot so I have no clue if that is reasonable)
        ddalex 7y ago
        The plane attitude (what you can sense with gyros) and angle of attack are very different things. They only coincide in level flight with no wind (the attitude is measured to the earth frame of reference (transposed by gyros) and the AoA is measured with reference to the local wind stream)
        glenneroo 7y ago
        OK then why not put a couple extra AoA sensors in? I thought everything critical on airliners was supposedly redundant?
    - peteradio 7y ago
      That is not what is wrong with the plane.
    - groby_b 7y ago
      This has very little to do with the plane's ability to glide. (A 737 glides just fine, if a bit steep for my taste). In that particular emergency, the control surfaces prevent it from gliding. You can even have issues on a Cessna - loss of elevator is not fun.[1] It's not about "denying physics", it's about having insufficient redundancy[2] and improper amount of control from MCAS - 3 times more than the FAA approved: [3] No plane is 100% safe. Boeing made this one worse for the sake of saving money - the physics work out just fine, and gliding ability is not really impacted. (But I don't think it'd be a normal response - I can't imagine a pilot thinking "oh, I'm getting a stall warning with nose down at 4,000 feet, I know, I'll cut power and glide".) [1] https://airfactsjournal.com/2018/12/elevator-failure-at-4500-feet-in-a-cessna-150/ https://airfactsjournal.com/2018/12/elevator-failure-at-4500... [2] https://www.seattletimes.com/business/boeing-aerospace/a-lack-of-redundancies-on-737-max-system-has-baffled-even-those-who-worked-on-the-jet/ https://www.seattletimes.com/business/boeing-aerospace/a-lac... [3] https://www.seattletimes.com/business/boeing-aerospace/failed-certification-faa-missed-safety-issues-in-the-737-max-system-implicated-in-the-lion-air-crash/ https://www.seattletimes.com/business/boeing-aerospace/faile...
  - tomglynch 7y ago
    Boeing seem to be pushing part of the blame to the pilot's -"Pilot error" - but this isn't due to 'lack of training' but the fact there was NO training and MCAS was not included in the manuals [1][2]. [1] https://www.seattletimes.com/business/boeing-aerospace/u-s-pilots-flying-737-max-werent-told-about-new-automatic-systems-change-linked-to-lion-air-crash/ https://www.seattletimes.com/business/boeing-aerospace/u-s-p... > Jon Weaks, president of the Southwest Airlines Pilots Association, said Monday the airline and the pilots “were kept in the dark.” “We do not like the fact that a new system was put on the aircraft and wasn’t disclosed to anyone or put in the manuals,” he said in an interview. What’s more, he noted, Boeing and the Federal Aviation Administration have now warned “that the system may not be performing as it should.” [2] https://theaircurrent.com/aviation-safety/what-is-the-boeing-737-max-maneuvering-characteristics-augmentation-system-mcas-jt610/ https://theaircurrent.com/aviation-safety/what-is-the-boeing... > "Since it operates in situations where the aircraft is under relatively high g load and near stall, a pilot should never see the operation of MCAS. As such, Boeing did not include an MCAS description in its FCOM. The explainer continues: "In this case, MCAS will trim nose as designed to assist the pilot during recover, likely going unnoticed by the pilot." There is another explanation, according to a Tuesday report in The Wall Street Journal: "One high-ranking Boeing official said the company had decided against disclosing more details to cockpit crews due to concerns about inundating average pilots with too much information - and significantly more technical data - than they needed or could digest."
hammock 7y ago
Because it focuses blame on the airlines and pilots for executing poor judgment, and suggests that Boeing didn't create any risk that the downstream parties weren't aware of or in control of.

StreamBright 7y ago

In one it helps them, pushing the narrative that more training would have avoided the disaster, on the other hand this questions if MAX should have been approved by FAA as a 737 variant that does not require re-training.

tomglynch 7y ago
If I'm not mistaken, Boeing themselves were the auditor for this on behalf of the FAA.
- tremon 7y ago
  It is both. FAA establishes guidelines for planes and designs to meet, and the airlines (not just Boeing) are responsible for certifying and rating their planes according to those guidelines. This is not simply a case of regulatory capture, the FAA simply doesn't have the expertise and in-depth knowledge to perform completely independent verification. Requiring the FAA to do so might be prohibitively expensive, so this arrangement is the result of pragmatic realism more than regulatory capture. It does require a great amount of trust between all partners though, and it seems to me Boeing has been more than happy to skirt their responsibility in this case.
  - dillonmckay 7y ago
    You say airlines, but I think you mean airplane manufacturers? Perhaps the airplane manufacturer and certifier should be separate manufacturers? How is the NHTSA able to certify crash tests for every make and model vehicle sold each year?
    - tomglynch 7y ago
      The FAA delegate much of the certification to Boeing [1], and to me it seems either the FAA is underfunded, or Boeing was in bed with the FAA to push things through quicker. [1] https://www.seattletimes.com/business/boeing-aerospace/failed-certification-faa-missed-safety-issues-in-the-737-max-system-implicated-in-the-lion-air-crash/ https://www.seattletimes.com/business/boeing-aerospace/faile...