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I do not understand why there isn’t more uproar about Boeing. 346 people are dead because of grievous and clearly attributable error. Relying on one sensor is bonkers, as literally everyone who is asked agrees. In the name of expediency and cost saves. nytimes.com/2019/06/01/bus…
The original MCAS design was meant to trigger only in extremely rare circumstances 
But the plane still had problems. So MCAS use case expanded dramatically, making it much more likely to trigger. Oh, and:
“modern 737 jets have two angle-of-attack sensors, the final version of MCAS took data from just one”
“modern 737 jets have two angle-of-attack sensors, the final version of MCAS took data from just one”
“That’s nuts”
“I’m shocked”
“It seems like somebody didn’t understand what they were doing”
“I’m shocked”
“It seems like somebody didn’t understand what they were doing”
Demon of Our Own Design is a great book. It has one of the best intro sentences of all time: “let’s just say I was in the vicinity”.
Bookstaber talks about tight coupling: “components of a process are critically interdependent”
“Flying an airplane is fraught with tightly coupled processes”
Interactive complexity
The greatest dangers arise when there is both interactive complexity and a tightly coupled system
Making a tightly coupled interactively complex system reliant on one sensor is “nuts”
This is worth a reread
Mistakes were made
“They could have designed a two channel system”
Not a great look
“Fix No. 1 to MCAS is that in version 12.1, it will take input from both sensors. If they disagree by 5.5 degrees or more, MCAS will shut down and not fire at all.”
Interesting article on testing the software upgrade to MCAS. But my god it’s incredible Boeing brought the original to market. wsj.com/articles/testi…
A key selling point of the Max was minimizing pilot training to save customers money
American now intends to train all its pilots
Again, a bunch of people are dead because Boeing dgaf
