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Thread: 777 Crash and Fire at SFO

  1. #901
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    I thought there had auto-throttle OFF, and they were convinced it was ON.

    Wasn't this the main cause on the crash? i.e. relying on some automatism (that was, in fact disengaged)

  2. #902
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    Quote Originally Posted by loupiote View Post
    I thought there had auto-throttle OFF, and they were convinced it was ON.

    Wasn't this the main cause on the crash? i.e. relying on some automatism (that was, in fact disengaged)
    They had autothrottle active, in IDLE hold, for the critical phase of flight that led them to a situation where they needed energy and had none available. If they were hand flying (i.e. hand on the thrust levers) this would have been more obvious to them.

    Of all the approaches in all the world, I can't think of a more appropriate one for straight in, stabilized autoflight ILS 3° final. And yes, the ILS is working just fine most of the time.

    As Gabriel said, large slow excursions are more indicative of manual flight. The 777 FBW will make very active control surface reactions for small deviations from the flight path via the FCC feedback loop. Depending on the A/T mode (speed on elevator vs speed on thrust, etc.), the thrust can be quite active as well. Even without autopilot, A/T is usually engaged, but I doubt anyone is recommending handflown approaches to SFO over ILS automation.

  3. #903
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    Ok, thanks. I stand corrected.

  4. #904
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    Gabe, No ILS with G/S = NO auto-land. New Guy, You would NEVER be able to tell if the auto-throttles were on from the back from them being "smooth" or not. The same goes for the aileron movement looking out the window. Depending on the flap setting the inboards are locked out and there will be more movement of the outboards. Sorry!

  5. #905
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    Quote Originally Posted by loupiote View Post
    I thought there had auto-throttle OFF, and they were convinced it was ON.

    Wasn't this the main cause on the crash? i.e. relying on some automatism (that was, in fact disengaged)
    Indeed. That was a primary factor (not sure about 'convinced'...perhaps 'assumed' is a better verb)

    However, since you are a private pilot,

    ...do you ever glance at the little gauge towards the upper left of the 6 main instruments?

    ...maybe reasonably often?

    ...maybe, do you watch it just a little bit closer on short final?

    ...maybe do you keep your hand on the throttle and add power if you get low and/or slow? (and possibly put a a small amount of nose down input for the slowness?)

    ...and even though you are not an instrument rated ATP with a 777 type rating, do you think it might be a good idea to glance at the airspeed on that really big jet much like you do in your __________ (please supply type)

    ...even if the big jet's autopilot and auto throttle and auto yaw damper and auto brakes and auto spoilers and automatic lavatory blue water injector and tank equalizing systems are all turned on?

    No flaming here- I want to know what your answers are!
    Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

  6. #906
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    Yes, air-speed is the most important parameter to monitor on final approach.

    And I always keep my hand on the throttle - except when I am piloting a glider in which case, we control the approach using air-brakes.

  7. #907
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    Quote Originally Posted by loupiote View Post
    Yes, air-speed is the most important parameter to monitor on final approach.
    Concur.

    Don't listen to Gabriel when he says AOA is most important, it's secondary, slightly secondary.
    Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

  8. #908
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    AoA is of course what determine is the aircraft is at risk of a stall, but in most smaller planes, there is no AoA sensor.

    And AoA is, in most cases, very related to air speed, when the plane is flying horizontally without major change of pitch, in a reasonably stable air mass.

    Of course if you do acrobatics or if the plane is in a very unorthodox position, you can go very slow with still a small AoA (like, at the top of a loop or lazy eight), or very fast with a high AoA. But in "normal" horizontal flight in a stable air mass, sufficient air-speed will be a very good indication that the AoA is in the safe region.

  9. #909
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    Quote Originally Posted by loupiote View Post
    AoA is of course what determine is the aircraft is at risk of a stall, but in most smaller planes, there is no AoA sensor.

    And AoA is, in most cases, very related to air speed, when the plane is flying horizontally without major change of pitch, in a reasonably stable air mass.

    Of course if you do acrobatics or if the plane is in a very unorthodox position, you can go very slow with still a small AoA (like, at the top of a loop or lazy eight), or very fast with a high AoA. But in "normal" horizontal flight in a stable air mass, sufficient air-speed will be a very good indication that the AoA is in the safe region.
    ...But there's one other sentence you are required to say.

    Remember, if you dive at your girlfriend's house, you'll probably have pretty good airspeed...
    Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

  10. #910
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    But in "normal" horizontal flight in a stable air mass, sufficient air-speed will be a very good indication that the AoA is in the safe region.
    True, but stalls very rarely happen in "normal" horizontal flight.

  11. #911
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    Default New Video

    New video from what appears to be an airport cam.

    https://www.yahoo.com/news/video-shows-more-fatal-2013-san-francisco-airliner-005222903.html




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