Boeing - Design Issues...

Discussion in 'Rules and Regulations / Flight Safety / Better Pil' started by TXFlyGuy, Apr 11, 2019.

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  1. May 1, 2019 #81

    Jerry Lytle

    Jerry Lytle

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    A lot of good comments here. Any ideas of what contributed to the excessive speads recorded for the Ethiopian crash.
     
  2. May 1, 2019 #82

    BBerson

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    If the autopilot won't engage with bogus conflicting inputs then MCAS should not engage either.
    It seems the designers and approvers of MCAS stepped into a new era where pilots are not allowed the final control.
    At least not without having some superhuman ability to outwit the MCAS while under conflicting stress.
     
  3. May 1, 2019 #83

    BJC

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    Yup, grab the trim wheel, or operate two side-by-side switches.


    BJC
     
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  4. May 1, 2019 #84

    BBerson

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    So if the stick shakers are activated in the clouds, should the first pilot reaction be to pull up and turn off the trim? Of course not, but with a MCAS malfunction it would need to be the first reaction.
     
    Last edited: May 2, 2019
  5. May 1, 2019 #85

    davidb

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    Agreed. That is part of the software fix moving forward. There’s many combinations of system design and pilot knowledge that could have averted these tragedies. Those will all be in place before we get to fly it again.
     
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  6. May 1, 2019 #86

    Vigilant1

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    In IMC (which neither of these crashes were), the first step would be to confirm the stick shaker indication. There's already an indication that something might be amiss because only one shaker is on, so check the AoA on the other side. Use both AoA indicators and the artificial horizon/gyro instruments.
    That will resolve much of the mystery. Then apply controls as required. The trim switches still work fine, though they may re-cycle nose down after 5-10 seconds . Disconnect the trim with the switches and trim manually with the wheel. Keep it trimmed and control pressures will never get excessive.
     
    Last edited: May 2, 2019
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  7. May 1, 2019 #87

    BBerson

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    That's good news.
     
  8. May 1, 2019 #88

    davidb

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    Are you a pilot?
     
  9. May 1, 2019 #89

    BBerson

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    That's my fear. When seconds count the pilot should be not confirming and disabling these malfunctioning safety layers. Why even have a pilot at all?
    In my view at this point, MCAS caused these crashes. Of course the final report will take a year or more.
     
  10. May 1, 2019 #90

    davidb

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    Are you asking about the physics or about the human factors?
     
  11. May 1, 2019 #91

    BBerson

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    Sorry, my post 84 was intended as a rhetorical question. Perhaps not appropriate response. I edited the post 84.
    I will sit out now.
     
    Last edited: May 2, 2019
  12. May 2, 2019 #92

    kgwilson

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    Self certification is a failure of concept. The fact that it has crept in over time as governments cut funding and services is a slow slide in the wrong direction. Profit is what drives companies to exist and they will do only what is absolutely necessary to keep costs down and their product competitive.

    It is absolutely obvious that commercial considerations completely trumped safety considerations. Boeing was so desperate to get back in the single aisle jet sales race to recoup some lost market share that their financial masters called the shots. The MCAS detail was deleted from the manual and they forgot to remove its definition from the glossary. This simple error shows to me when those people who were told to make the changes did so under some duress and while it could have been an oversight it also may not have been. Boeing had a good reputation. It doesn't any more. You can't buy a reputation after you have thrown it away.

    The 737 was renamed 737 NG (New Generation) in 1993 with 4 variants carrying between 110 and 210 passengers and is the 3rd generation of the airliner following the classic which began production in the 1980s. At that stage the new engine cowls had to be flattened at the bottom to provide adequate ground clearance. As we know the Max engines were just too big so had to be moved forwards and upwards to achieve adequate clearance. The NEO is the Airbus A320 NEO (New Engine Option) introduced in 2010
     
  13. May 2, 2019 #93

    bmcj

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    As government cuts engineer/inspectors, self certification becomes the default fallback. However, it might be said that self certification goes beyond product delivery as the customers become part of the vetting process. If the government doesn’t step in, then the level and detail of self certification will adjust, in part, according to how much market share they lose.
     
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  14. May 2, 2019 #94

    davidb

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    But that is a primary role of the pilot. Pilots are trained to verify and quickly analyze warnings and alerts. Pilots aren’t and shouldn’t be machines. They are the safety layer with cognition and the ability to react to unforeseen circumstances.

    It takes a split second to determine if the stick shaker is a false warning or an actual impending stall. Think of it as an alert to the pilot that has somehow been distracted away from flying or monitoring the autopilot. It quickly gets your attention focused if you were distracted away from flying the airplane. On takeoff or other times when your attention is focused on flying to precision parameters, a bogus stick shaker is instantly apparent.

    We all want perfect aircraft with no chance of taxing a pilot’s ability to safely operate. Boeing certainly missed the mark. The flip side is we should all want perfect pilots. I think more and better training is actually just as important. When you achieve a design that only has a one in a billion chance of failure, wouldn’t you still want a pilot trained to handle that failure? Not rhetorical.
     
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  15. May 2, 2019 #95

    BJC

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    It would be interesting to see the history of the root causes of commercial air transport crashes both world wide and in the USA. I suspect that the vast majority over that past thirty or forty years were caused by pilot or controller error. We may be transitioning to an era where the root causes will primarily be problems with the aircraft design.

    In either case, the overall safety record of USA and many European carriers is outstanding.

    Wrt self certification, what would happen to the quality / safety record of USA air carriers if the FAA were eliminated today?


    BJC
     
  16. May 2, 2019 #96

    Hot Wings

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    Don't forget the lawyers - they won't let us. :eek: :D

    The customers also only have a say in the process if there is real competition in the market. There appears to be plenty of competition at the LSA/Experimental level but maybe not enough between Boeing and Airbus?

    The way things are shaping up in the media, that I've seen, the customers may have a say with the Max. Boeing may have to change the name?o_O
     
  17. May 2, 2019 #97

    TXFlyGuy

    TXFlyGuy

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    How did the pilots of AF 447 fair in this environment?
     
  18. May 2, 2019 #98

    litespeed

    litespeed

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    My apologies over mixing up A320 neo and 737 ng.

    I was commenting on the 737 ng.

    No one has commented on the 737 ng been built in a uncertified manner.

    What are your thoughts?
     
  19. May 2, 2019 #99

    BJC

    BJC

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  20. May 2, 2019 #100

    litespeed

    litespeed

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    That is just corporate speil about the max.

    Does not address the potential the 737 ng was not certified under the letter of law.
     

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