Planes Thread

Discussion in 'Off Topic' started by Jarhead, Dec 29, 2015.

  1. hmscott

    hmscott Notebook Nobel Laureate

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    Last edited: Mar 25, 2019
  2. hmscott

    hmscott Notebook Nobel Laureate

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    Boeing 737 MAX 8 - Start and Takeoff Procedures - Santa Cruz - Bolivia
    Mr Fabio
    Published on Jul 24, 2018
     
  3. killkenny1

    killkenny1 Too weird to live, too rare to die.

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    That's AOA disagree light, and both crashed planes lacked that feature.
    IIRC 737 MAX has 2 Angle Of Attack sensors, and under normal ops each pilot gets data from their own AOA sensor. What Boeing sold safety feature does is compare the data between the two so that there is no discrepancies between the two. If there are, it makes a warning.
     
  4. hmscott

    hmscott Notebook Nobel Laureate

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    OMG, that's nutz, an option? I would think that would be a required if not obvious fail-safe built in to the software to validate the sensor data. With not only a warning light but a quick disconnect of the autopilot and / or MCAS.

    How can the autopilot / MCAS software manage the flight attitude without valid AOA data? That seems pretty basic, not an option.
     
    Last edited: Mar 25, 2019
  5. killkenny1

    killkenny1 Too weird to live, too rare to die.

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    Thing is, the whole MCAS thingy that they are having problem with was meant to be safety feature during hand flying (aka autopilot disengaged).
     
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  6. hmscott

    hmscott Notebook Nobel Laureate

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    Right, MCAS only comes on during manual controlled flight. Aren't the AOA sensors used as part of the autopilot function as well? I would assume that bad AOA data would be bad for either / both autopilot and/or MCAS.

    Edit: Maybe not, I thought American added AOA sensors to their autopilot software in the 90's, but it looks like it's an independent add-on. Here's an add-on's for "reasonable" money (not $80k):

    Standalone Angle-of-Attack: AOA Pro & Sport
    An AOA instrument is something every aircraft builder should consider.
    http://www.advancedflightsystems.com/advanced-aoa.php
     
    Last edited: Mar 25, 2019
  7. hmscott

    hmscott Notebook Nobel Laureate

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    An earlier computer vs man autopilot issue:

    When 'psycho' automation left this pilot powerless
    The Sydney Morning Herald
    Published on May 14, 2017
    For the first time since 2008, the captain of the imperilled Qantas Flight 72 reveals his horrific experience of automation's dark side.
     
    Last edited: Mar 25, 2019
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  8. cucubits

    cucubits Notebook Consultant

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    Bad times for aviation. We're too advanced to fly completely manually yet the computers controlling things aren't very well designed to keep us safe.

    To be honest I can't wait for things to smooth out in all the automation areas and remove the human factor completely.
     
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  9. cucubits

    cucubits Notebook Consultant

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  10. hmscott

    hmscott Notebook Nobel Laureate

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    This report and others have been removed, they said the pilots turned off the MCAS stabilizer trim power per procedure, but then turned it back on just before the crash.

    New details on pilots' actions in Ethiopian Airlines crash

    ABC News
    Published on Apr 3, 2019
    Plus, the latest on Boeing's software fix delay that will keep the fleet of Boeing 737 Max planes grounded, cancelling more than 200 flights in one day in the U.S. alone.
     
    Last edited: Apr 5, 2019
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