Boeing 717 Deep Stall - Flight Test

Discussion in 'Flight Following' started by Ryan A, Jul 15, 2020.

  1. Ryan A

    Ryan A Filing Flight Plan

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    Just came across this on YouTube. Doesn't look like it has been posted here before.

    Pretty scary situation, especially with how far over Vne they were during the recovery.



    Any ideas as to why not just use ailerons to roll back to level instead of the "split-s"-style recovery?
     
  2. Doc Holliday

    Doc Holliday Pattern Altitude

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    Been posted on here several times. But still fun to watch.
     
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  3. smv

    smv Pattern Altitude

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    I am no 717 pilot, but my guess is by the time they got the nose down with enough airspeed to break the stall and make the ailerons effective, they were already vertical and all they needed to do at that point was recover from the dive.

    Using ailerons to try to "pick up" the wing in a stall is a pretty sure way to find yourself in a spin.
     
  4. Shepherd

    Shepherd En-Route

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  5. Larry in TN

    Larry in TN Pattern Altitude

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    Douglas built strong airplanes.
     
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  6. ChemGuy

    ChemGuy Cleared for Takeoff

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    What Doc said. Also I think i read somewhere that the wing or something was bent or out of rig and thats why it snapped over so hard.
     
  7. Maxnr

    Maxnr Pre-takeoff checklist

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    Why not ailerons? What do I know? I'm just a working class pilot. But one who was taught from the get-go to not input aileron when stalled. My basic understanding of a deep stall is when a high angle of attack causes the Tee tail to be blanked by the wake of the wing and becomes ineffective. I never read far enough to understand the recovery.
    I'm never surprised by what a test pilot does. I'm pretty sure this was tested in the wind tunnel first.
     
  8. 3393RP

    3393RP En-Route

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    No big deal. They only lost 18,000' while recovering. :eek:
     
  9. smv

    smv Pattern Altitude

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    ...but did they do their CHAPS checklist before the maneuver?
     
  10. Arm3

    Arm3 Filing Flight Plan

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    Legend has it the seat cushions still haven’t been recovered.
     
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  11. Jeff767

    Jeff767 Pre-takeoff checklist

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    Ailerons while stalled equals a spin in many high performance aircraft. One aircraft I flew considered it so important that if in a stall we put our elbows up wedged against the canopy rails to insure the ailerons remained dead neutral. I saw nothing like a split S recovery in the video.
     
  12. Seanaldinho

    Seanaldinho Pattern Altitude

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    To add on to everyone else...

    Ailerons are not your friend in a stall.

    Roll authority isn't great in any airliner therefore prolonging the recovery.

    Pulling straight back kept the load positive rather than allowing any negative load in. Most systems (including humans) are built to withstand much stronger positive loads than negative and the test pilots would want to rule out as many variables as possible.
     
  13. Ventucky Red

    Ventucky Red Cleared for Takeoff

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    In Long Beach, CA... "where da hood meets the good... if it is not the roar of the FedEx 767 it is the report' of a 357"

    Still remember the day the last one rolled of the line... :(
     
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