Comments by "Tim Trewyn" (@timtrewyn453) on "Boeing's Fatal Flaw (full documentary) | FRONTLINE" video.

  1. I remember in engineering college the emphasis on modeling systems on paper and, if possible, in computer simulation before you build them, because it is cheaper to find a problem and fix it then. More powerful computers and software can and have improved modeling. If you rush the modeling process, then you are just asking for trouble later on. Of course, prototypes are also very valuable for rooting out things the modeling process may have missed but rushing that as well compounds the potential problems down the road. It happens again and again with automobile recalls. And although I am not an aeronautical engineer, I do somewhat wonder about the fix of adding another AOA sensor as enough to rule out the problem. If an AOA has a obscure vulnerability, both AOAs might fail when presented with that vulnerability. If you have a computer controlling the envelope, then why wouldn't airspeed and altimeter indications, even pilot vitals of some kind like asking the crew to reply with a word, show the program that continuing to pitch the nose is going to take the plane into the ground? It seems to me that the software still is not thorough in modeling and coping with near envelope scenarios. I mean, once MCAS starts a stall correction, should it not have a time parameter that is the outer boundary of how long a stall takes to be corrected and give control back to the pilot if MCAS cannot correct the stall? There just seems to be all kinds of parameters available to be checked and indicate to the program and pilots that some parameter has become untrustworthy and nullify its input. It sounds like this AOA addition is still a safety feature quick fix instead of a thorough modeling of the aircraft envelope and writing the software accordingly. I can imagine this is a huge task requiring many more lines of code and the computer processing power to cope with that (a testament to the value of a pilot), but public confidence in air travel should be the foundation of the business. As we can see, it not always is for those in leadership.
    1