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I shouldn't be surprised if there aren't several people within Boeing with exactly the right expertise. Whether they were identified and listened to by managem

I shouldn't be surprised if there aren't several people within Boeing with exactly the right expertise. Whether they were identified and listened to by management is a separate question. If Musk is right (IANA Battery Guy), I would presume there are cost / design trade-offs involved. And some exec had to evaluate those against safety issues. Those are engineering decisions, they're also business decisions. If the execs deciding that didn't have the proper background to make an engineering evaluation himself, they are left trying to decide which engineers to trust. It isn't at all hard to see someone getting that wrong.

starpilot 14y ago
I'm an aeromechanical engineer, not an electrical one, but I suspect the fewer-cells design was chosen to save weight. Many unconventional design decisions in aerospace (everything with holes, novel materials which trickle down to cars and golf clubs) are driven by the need to reduce weight.
- chernevik 14y ago
  These systems replaced hydraulics for surface control, right? On a weight advantage? Making good on a decision like that is exactly what confirmation bias is all about.
  - cpleppert 14y ago
    The hydraulics are controlled exactly the same as any other fly by wire aircraft like the 777 or a modern airbus. The computer takes the pilot inputs and combines them with a flight computer that controls electric motors which move the flight surfaces with hydraulics. The big increase in electrical supply (4x over the 777 i believe) is the result of the bleedless air architecture that boeing chose. There was a big push by boeing to make the system work as it was a selling point for the public and carriers. I think that decision didn't receive the scrutiny that it probably should have.
- deleted 14y ago
  [deleted]
fnordfnordfnord 14y ago
Yes, the situation you describe is not unlike the one at Morton Thiokol prior to the Challenger accident. You should look up the story of how Feynman (who was not an Aerospace engineer, gasp!) managed to bring the Challenger accident cause to light, despite some of the accident investigation committee's best efforts.

starpilot 14y ago

I'm an aeromechanical engineer, not an electrical one, but I suspect the fewer-cells design was chosen to save weight. Many unconventional design decisions in aerospace (everything with holes, novel materials which trickle down to cars and golf clubs) are driven by the need to reduce weight.

chernevik 14y ago
These systems replaced hydraulics for surface control, right? On a weight advantage? Making good on a decision like that is exactly what confirmation bias is all about.
- cpleppert 14y ago
  The hydraulics are controlled exactly the same as any other fly by wire aircraft like the 777 or a modern airbus. The computer takes the pilot inputs and combines them with a flight computer that controls electric motors which move the flight surfaces with hydraulics. The big increase in electrical supply (4x over the 777 i believe) is the result of the bleedless air architecture that boeing chose. There was a big push by boeing to make the system work as it was a selling point for the public and carriers. I think that decision didn't receive the scrutiny that it probably should have.
deleted 14y ago
[deleted]

fnordfnordfnord 14y ago

Yes, the situation you describe is not unlike the one at Morton Thiokol prior to the Challenger accident. You should look up the story of how Feynman (who was not an Aerospace engineer, gasp!) managed to bring the Challenger accident cause to light, despite some of the accident investigation committee's best efforts.