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21 sats \ 4 replies \ @clr 21 Jan freebie \ parent \ on: Fighting The Cancer Of Society culture
The 737 Max problem, as someone explained very well on Twitter:
  1. Boeing wanted to create an alternative to the A320neo, but it couldn't be a new model, because that means that the pilots must receive long training and simulator sessions before they are FAA certified to fly a new plane model.
  2. So Boeing decided to improve the 737 rather than design a new plane from scratch.
  3. They chose a new engine with a higher bypass ratio for higher fuel efficiency, but the new engine has a bigger diameter than the older one. The 737 has a low landing gear, so the new engine would be too close to the ground.
  4. The solution was to move the engine forward in front of the wing so that it could be higher.
  5. This changed the flying behavior of the plane. Maybe it moved the gravity center of the plane and/or it increased the "wing" surface because the engine now was forward rather than below the wing. Bottom line, the 737 Max has a tendency to tilt upwards and it could get too vertical under certain circumstances.
  6. Remember, Boeing had promised to the airlines a 737 variant, not a new plane. So the new plane needed to have the same behavior as the previous 737.
  7. This is where the MCAS comes in. To avoid pilot recertification, the 737 Max had to "feel" like the previous 737 to the pilots. So they decided to compensate for the tilting upwards by using the elevator in the tail to counteract. This is done automatically by the plane without telling the pilots. The input sensor is the angle of attack sensor. Boeing chose to use only one sensor instead of building in redundancy. The training materials for the pilots only mentioned this whole new system in passing, so less experienced pilots wouldn't probably be fully aware of what had changed.
  • Boeing prioritized short term profits before long term sustainability. This can be at least in part be traced back to fiat/short term economy. The state, in short.
  • The FAA allowed and approved that design and that whole chain of fuckery.
  • Only after hundreds of people died they had to ground the planes because the problems couldn't be hidden anymore.
So no, the FAA is no hero in this story. They are the villains, together with Boeing.
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21 sats \ 1 reply \ @clr 22 Jan
Here is a source with a very detailed explanation: https://spectrum.ieee.org/how-the-boeing-737-max-disaster-looks-to-a-software-developer
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0 sats \ 0 replies \ @TomK OP 22 Jan
Cool. Very interesting. Thank You
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21 sats \ 1 reply \ @BlokchainB 22 Jan
Villains? Where is the malicious intent? They tried to innovate on a design and it failed. Things like this happen all the time. Even Satoshi had an inflation bug in the bitcoin protocol.
Blaming the state for Boeing’s design choices is a stretch. Aviation is a tough business with very low profit margin. But yet they brought the cost down to fly to where your normal middle class family can take 2 to 3 flights a year. The death rate for flying in a Boeing plane is near negligible.
Overall regulation is in place to protect people. Just like anything in life we have good regulation and bad regulation and overall enforcement of those regulations. Mind you if you hate it nothing is stopping you from flying with countries with lackluster regulations.
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100 sats \ 0 replies \ @clr 22 Jan
I am not sure if you have read this post: https://spectrum.ieee.org/how-the-boeing-737-max-disaster-looks-to-a-software-developer
It's long but well worth reading. It answers all your questions.
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