6 ms·

Except, of course, from Boeing's aircraft-software QA... which killed hundreds of people already.

actionfromafar 3y ago
The problem was not really the software in isolation, but that pilots expected the 737 NG to behave exactly like the old version - because Boeing decided it was too expensive to retrain pilots.
- WalterBright 3y ago
  The expense for retraining pilots falls on the airline. Retraining has its own problems. No matter how well retraining is done, pilots still make mistakes from doing the right thing for the previous plane that is the wrong thing for the one they are currently flying. Adjusting airplanes to fly the same way is a major safety advantage.
  - ethbr1 3y ago
    Arguably, Boeing hit the uncanny safety valley -- similar enough so that pilots and airlines relaxed, but different enough so that relaxation ultimately killed people.
    - WalterBright 3y ago
      The emergency procedure for runaway trim was the same for both aircraft types, and was not followed. After the first crash, an Emergency Airworthiness Directive was issued to all MAX pilots reiterating the procedure, which was not followed in the second crash, as well as not reacting to an overspeed warning. Unreported by the media, there was another MAX incident before the first crash. The crew had no knowledge of MCAS, but did follow the emergency runaway trim procedure, and continued the flight and landed safely.
      - 9659 3y ago
        "Runaway stab trim". It is a memory item, every pilot should be able to perform it from memory. Turn off the motor, and the trim is manual. There is a crank right there in the cockpit. If it is too hard to turn, change aircraft configuration to reduce the forces required to. Pilot know how to do this. This pilot stuff, they understand the forces on the flight controls and what impacts them. Boeing made an engineering mistake. The pilots also made an operational mistake. Unfortunately, both mistakes at the same time were fatal. I pray that pilot training has improved. And that Boeing has made systems level changes to the aircraft that will preclude it happening in the future. And that is how aviation becomes safer every year; at a significant cost of customers lives.
        ethbr1 3y ago
        > And that is how aviation becomes safer every year; at a significant cost of customers lives. "Significant" might be inaccurate. It looks like FAA Part 121 accidents over the last 10 years with fatalities have been... 4. [0] For a total of 6 fatalities. [0] https://www.ntsb.gov/Pages/AviationQueryV2.aspx https://www.ntsb.gov/Pages/AviationQueryV2.aspx; 2018 (1 passenger fatality) https://www.ntsb.gov/investigations/Pages/DCA18MA142.aspx https://www.ntsb.gov/investigations/Pages/DCA18MA142.aspx ; 2019 (3 crew fatalities, cargo flight) https://www.ntsb.gov/investigations/Pages/DCA19MA086.aspx https://www.ntsb.gov/investigations/Pages/DCA19MA086.aspx and (1 passenger fatality) https://www.ntsb.gov/investigations/Pages/DCA20MA002.aspx https://www.ntsb.gov/investigations/Pages/DCA20MA002.aspx ; 2022 (1 ramp fatality) https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/106517/pdf https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/G...
        WalterBright 3y ago
        That low accident rate is nigh inconceivable. It's an incredible achievement.
        ethbr1 3y ago
        The fatal accident count is higher for GA, but I didn't normalize against flight hours or flights, just glanced at it. I'm sure there's been a study somewhere that attempts to untangle all the factors that differ between commercial carriers and GA, to see which safety is most sensitive to -- continuous highly professional maintenance, highly trained and experienced crew, rigorous airliner certification regime, etc.
  - ShadowBanThis01 3y ago
    If a pilot can't be expected to maintain the pitch of a plane on takeoff, he has no business flying ANYTHING. What Boeing did (and is STILL doing) is expect pilots to know or remember obscure NON-PILOTAGE (and in the case of MCAS, BURIED) trivia to prevent disaster. Now... what's the more-responsible approach? Expect pilots to pilot, or expect them to recall an ever-growing list of workarounds to incompetent system design?
    - gmokki 3y ago
      The whole MCAS was just unnecessary feature (bug fix). Without it the plane would have worked just fine. The pilots would just have had to go some amount of training scenarios to get the certification on how the MAX plain flies.
      - ShadowBanThis01 3y ago
        Exactly. Unless the "upward-pitching tendency" under high power is extreme, any competent pilot should be able to keep the plane's attitude as desired.
- unyttigfjelltol 3y ago
  The problem was software that prioritized input from a fauly external sensor, over pilot control, and literally crashed planes directly into the ground. At a certain step in the sequence it was not physically possible for a pilot to pull hard enough on the control element to counteract the software. Could they have disabled the system? Only if they could figure out the specific software trying to crash the plane. Is that what you meant by "the problem wasn't the software?" Because the pilots should have been trained to unplug the computer to stop it from crashing the plane?
  - ethbr1 3y ago
    Pilots are definitely trained how to disable the autopilot, if needed. Afaic, the fault apportionment was Boeing documentation > airlines >> pilots > Boeing technical design.
    - diabeetusman 3y ago
      Not sure why you’re bringing up autopilot— the MCAS system runs even when the autopilot is disabled. Edit: Also, how does the fault lie with the airlines? Boeing didn’t document the existence of MCAS in the flight manual or training materials.
      - ethbr1 3y ago
        Because the comment I was replying to >> Because the pilots should have been trained to unplug the computer to stop it from crashing the plane? Yes. The fault lies with the airlines because I don't for a second believe they didn't put pressure on Boeing to get the MAX certified without mandating retraining. And then once that was done, didn't dig into the details too hard about what changes were made. I have a low tolerance for 'I set up all the conditions and incentives to encourage you to break the law... but you should take all the blame when it explodes.' At some point, the customer has to take some responsibility for what they asked for.
        actionfromafar 3y ago
- ShadowBanThis01 3y ago
  Wrong.

The problem was not really the software in isolation, but that pilots expected the 737 NG to behave exactly like the old version - because Boeing decided it was too expensive to retrain pilots.

WalterBright 3y ago
The expense for retraining pilots falls on the airline. Retraining has its own problems. No matter how well retraining is done, pilots still make mistakes from doing the right thing for the previous plane that is the wrong thing for the one they are currently flying. Adjusting airplanes to fly the same way is a major safety advantage.
- ethbr1 3y ago
  Arguably, Boeing hit the uncanny safety valley -- similar enough so that pilots and airlines relaxed, but different enough so that relaxation ultimately killed people.
  - WalterBright 3y ago
    The emergency procedure for runaway trim was the same for both aircraft types, and was not followed. After the first crash, an Emergency Airworthiness Directive was issued to all MAX pilots reiterating the procedure, which was not followed in the second crash, as well as not reacting to an overspeed warning. Unreported by the media, there was another MAX incident before the first crash. The crew had no knowledge of MCAS, but did follow the emergency runaway trim procedure, and continued the flight and landed safely.
    - 9659 3y ago
      "Runaway stab trim". It is a memory item, every pilot should be able to perform it from memory. Turn off the motor, and the trim is manual. There is a crank right there in the cockpit. If it is too hard to turn, change aircraft configuration to reduce the forces required to. Pilot know how to do this. This pilot stuff, they understand the forces on the flight controls and what impacts them. Boeing made an engineering mistake. The pilots also made an operational mistake. Unfortunately, both mistakes at the same time were fatal. I pray that pilot training has improved. And that Boeing has made systems level changes to the aircraft that will preclude it happening in the future. And that is how aviation becomes safer every year; at a significant cost of customers lives.
      - ethbr1 3y ago
        > And that is how aviation becomes safer every year; at a significant cost of customers lives. "Significant" might be inaccurate. It looks like FAA Part 121 accidents over the last 10 years with fatalities have been... 4. [0] For a total of 6 fatalities. [0] https://www.ntsb.gov/Pages/AviationQueryV2.aspx https://www.ntsb.gov/Pages/AviationQueryV2.aspx; 2018 (1 passenger fatality) https://www.ntsb.gov/investigations/Pages/DCA18MA142.aspx https://www.ntsb.gov/investigations/Pages/DCA18MA142.aspx ; 2019 (3 crew fatalities, cargo flight) https://www.ntsb.gov/investigations/Pages/DCA19MA086.aspx https://www.ntsb.gov/investigations/Pages/DCA19MA086.aspx and (1 passenger fatality) https://www.ntsb.gov/investigations/Pages/DCA20MA002.aspx https://www.ntsb.gov/investigations/Pages/DCA20MA002.aspx ; 2022 (1 ramp fatality) https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/106517/pdf https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/G...
        WalterBright 3y ago
        That low accident rate is nigh inconceivable. It's an incredible achievement.
        ethbr1 3y ago
        The fatal accident count is higher for GA, but I didn't normalize against flight hours or flights, just glanced at it. I'm sure there's been a study somewhere that attempts to untangle all the factors that differ between commercial carriers and GA, to see which safety is most sensitive to -- continuous highly professional maintenance, highly trained and experienced crew, rigorous airliner certification regime, etc.
- ShadowBanThis01 3y ago
  If a pilot can't be expected to maintain the pitch of a plane on takeoff, he has no business flying ANYTHING. What Boeing did (and is STILL doing) is expect pilots to know or remember obscure NON-PILOTAGE (and in the case of MCAS, BURIED) trivia to prevent disaster. Now... what's the more-responsible approach? Expect pilots to pilot, or expect them to recall an ever-growing list of workarounds to incompetent system design?
  - gmokki 3y ago
    The whole MCAS was just unnecessary feature (bug fix). Without it the plane would have worked just fine. The pilots would just have had to go some amount of training scenarios to get the certification on how the MAX plain flies.
    - ShadowBanThis01 3y ago
      Exactly. Unless the "upward-pitching tendency" under high power is extreme, any competent pilot should be able to keep the plane's attitude as desired.
unyttigfjelltol 3y ago
The problem was software that prioritized input from a fauly external sensor, over pilot control, and literally crashed planes directly into the ground. At a certain step in the sequence it was not physically possible for a pilot to pull hard enough on the control element to counteract the software. Could they have disabled the system? Only if they could figure out the specific software trying to crash the plane. Is that what you meant by "the problem wasn't the software?" Because the pilots should have been trained to unplug the computer to stop it from crashing the plane?
- ethbr1 3y ago
  Pilots are definitely trained how to disable the autopilot, if needed. Afaic, the fault apportionment was Boeing documentation > airlines >> pilots > Boeing technical design.
  - diabeetusman 3y ago
    Not sure why you’re bringing up autopilot— the MCAS system runs even when the autopilot is disabled. Edit: Also, how does the fault lie with the airlines? Boeing didn’t document the existence of MCAS in the flight manual or training materials.
    - ethbr1 3y ago
      Because the comment I was replying to >> Because the pilots should have been trained to unplug the computer to stop it from crashing the plane? Yes. The fault lies with the airlines because I don't for a second believe they didn't put pressure on Boeing to get the MAX certified without mandating retraining. And then once that was done, didn't dig into the details too hard about what changes were made. I have a low tolerance for 'I set up all the conditions and incentives to encourage you to break the law... but you should take all the blame when it explodes.' At some point, the customer has to take some responsibility for what they asked for.
      - actionfromafar 3y ago
ShadowBanThis01 3y ago
Wrong.