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> At the time that would have been a very difficult decision to make internally at Boeing, given that the 737MAX has $250 Billion worth of orders That is exac

by jussij 8y ago

> At the time that would have been a very difficult decision to make internally at Boeing, given that the 737MAX has $250 Billion worth of orders That is exactly right and exactly why they need to be nailed for this. No hindsight is required to know Boeing was focused on making sure the welfare of Boeing and it's shareholders was taken care of, with little or no regard to the welfare of the flying public.

KMag 8y ago
It's not that simple. There's no denying that there was tremendous commercial pressure, but ... from a single data point (prior to the second crash), it wasn't obvious that the risk of continuing to fly the aircraft was greater than grounding the planes, which results in cancelled flights and greater risk of road deaths due to some passengers taking road alternatives instead of re-booking flights. Also, the 737 MAX is a longer-range aircraft, and some of the slack would be taken up by capacity in shorter-range aircraft, converting direct flights to multi-leg flights, where most of the risk is in takeoff and landing. All else being equal, more flight legs means more risk. Some of the slack would be taken up by smaller regional airlines flying older planes, and I'm not sure how those safety records generally compare to larger airlines flying newer planes. In any case, I expect the majority of the offsetting risk would be from people deciding to drive when their flights got cancelled. Now that we see that training and procedural changes appear to be a less effective mitigant than expected, we can say that with a high degree of certainty that the risk of increased road deaths does not offset the risks of continuing to fly the aircraft.
- jussij 8y ago
  > from a single data point (prior to the second crash), it wasn't obvious that the risk of continuing to fly the aircraft was greater than grounding the planes Call me a skeptic but I have no doubt Boeing was well aware of the issue with the MCAS well before that first data point. Even before that first crash, there have been reports in the media that claim many pilots had complained about the dangers of the MCAS.
  - ejstronge 8y ago
    > Even before that first crash, there have been reports in the media that claim many pilots had complained about the dangers of the MCAS. I don't think this is true - the newspaper that first made this claim overstated their findings. Pilots, in general, did not know about MCAS before the Lion Air crash.
    - jussij 8y ago
      This has very little to do with the existence of the MCAS but instead was the plane actually safe to fly and when did information come to hand to show that it was not. Consider this link: https://www.abc.net.au/news/2019-03-13/737-max-pilots-reported-two-control-issues-in-2018-to-nasa/10895542 https://www.abc.net.au/news/2019-03-13/737-max-pilots-report... From that link: Airline pilots on at least two US flights have reported that an automated system seemed to cause their Boeing 737 MAX 8 planes to tilt down suddenly. That reporting suggests problems were known well in advance of the first crash.
- Bendingo 8y ago
  > and greater risk of road deaths due to some passengers taking road alternatives Such a consideration (while valid) is not Boeing's to make.
- cjbprime 8y ago
  Almost no-one decides they'll just drive instead of flying because their plane was delayed. After the first crash, Boeing certainly knew that it had hooked up MCAS to a single AoA vane. I don't think they could sincerely argue that hooking up a single sensor to a primary control surface with no backup sensor is airworthy -- either practically or legally. There are regulations about it, and that's why Airbus has three AoA vanes and uses majority quorum. That's why I think the grounding should have happened earlier.

by jussij 8y ago

KMag 8y ago

It's not that simple. There's no denying that there was tremendous commercial pressure, but ... from a single data point (prior to the second crash), it wasn't obvious that the risk of continuing to fly the aircraft was greater than grounding the planes, which results in cancelled flights and greater risk of road deaths due to some passengers taking road alternatives instead of re-booking flights. Also, the 737 MAX is a longer-range aircraft, and some of the slack would be taken up by capacity in shorter-range aircraft, converting direct flights to multi-leg flights, where most of the risk is in takeoff and landing. All else being equal, more flight legs means more risk. Some of the slack would be taken up by smaller regional airlines flying older planes, and I'm not sure how those safety records generally compare to larger airlines flying newer planes. In any case, I expect the majority of the offsetting risk would be from people deciding to drive when their flights got cancelled. Now that we see that training and procedural changes appear to be a less effective mitigant than expected, we can say that with a high degree of certainty that the risk of increased road deaths does not offset the risks of continuing to fly the aircraft.

jussij 8y ago
> from a single data point (prior to the second crash), it wasn't obvious that the risk of continuing to fly the aircraft was greater than grounding the planes Call me a skeptic but I have no doubt Boeing was well aware of the issue with the MCAS well before that first data point. Even before that first crash, there have been reports in the media that claim many pilots had complained about the dangers of the MCAS.
- ejstronge 8y ago
  > Even before that first crash, there have been reports in the media that claim many pilots had complained about the dangers of the MCAS. I don't think this is true - the newspaper that first made this claim overstated their findings. Pilots, in general, did not know about MCAS before the Lion Air crash.
  - jussij 8y ago
    This has very little to do with the existence of the MCAS but instead was the plane actually safe to fly and when did information come to hand to show that it was not. Consider this link: https://www.abc.net.au/news/2019-03-13/737-max-pilots-reported-two-control-issues-in-2018-to-nasa/10895542 https://www.abc.net.au/news/2019-03-13/737-max-pilots-report... From that link: Airline pilots on at least two US flights have reported that an automated system seemed to cause their Boeing 737 MAX 8 planes to tilt down suddenly. That reporting suggests problems were known well in advance of the first crash.
Bendingo 8y ago
> and greater risk of road deaths due to some passengers taking road alternatives Such a consideration (while valid) is not Boeing's to make.
cjbprime 8y ago
Almost no-one decides they'll just drive instead of flying because their plane was delayed. After the first crash, Boeing certainly knew that it had hooked up MCAS to a single AoA vane. I don't think they could sincerely argue that hooking up a single sensor to a primary control surface with no backup sensor is airworthy -- either practically or legally. There are regulations about it, and that's why Airbus has three AoA vanes and uses majority quorum. That's why I think the grounding should have happened earlier.