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Rapid uncontrolled descent

Discussion in 'Phantom 2 Vision + Help' started by ajohnson, Sep 16, 2014.

  1. ajohnson

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    This is likely a similar question as was posed a few days ago, but here goes. We recently purchased a Phantom 2 Vision + and have just taken our first flights. Because we are total newbies we do have the prop guards and strings attached. We went out flying today and had several instances where the quad more or less fell out of the sky. Certainly it wasn't like a stone falling, but it came down hard and completely out of our control. Once it happened when in a hover and once it happened while trying to bee-line it back to "base". I first thought that it might be a dead air issue when it was hovering, but when it happened while gong full forward that seemed unlikely. The battery phantom battery was at about 45% when it first happened and then progressively lower as it continued happening. Some answered "VRS" to the other post...what does that mean? Thanks in advance for any ideas. BTW flying conditions were warm (80s), inconsistent breeze, fairly humid (at least for SW CO).
     
  2. BWJ

    BWJ

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    Have you the latest SW installed ?
     
  3. ajohnson

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    We are just using it out of the box; should it have the latest software installed if we just received it last week?
     
  4. BWJ

    BWJ

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    Its a good idea to check it, both Controller and Phantom.
     
  5. Buckaye

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    VRS= vortex ring state

    It's a physics thing... Basically if your rapidly descending and pulling air through the rotors... Basically the heli gets into it's own down wash creating a state where the rotors no longer can produce lift. So the heli or quad just drops.
     
  6. noiseboy72

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    If it happens again, full left or right stick to get out of the disturbed air, then apply power to pull out of the death dive!

    Removing prop guards does help, but does not eradicate the issue. You need to learn to spot the very early signs - like instability, make sure you descend more slowly and when landing, fly into the wind on a glideslope, never with the wind behind the quad, as this make things much worse.
     
  7. Wedeliver

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    i am wondering if folks who are experiencing this "falling from the sky" issues might be turning off the props when they are trying to descend. To the op.. in VRS I have been told that your motor noise should get louder when this is occuring.
     
  8. ajohnson

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    All good ideas and it gives me something to look for. As a real beginner the subtleties are still a little foreign to me. I will go through today and make sure all software/firmware is up to date and that the controller is calibrated. If it continues to happen I'll see what other observations I can add to the discussion.
     
  9. archersc

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    I am a very experienced operator and this same scenario happened to me on three flights in a row recently. Definitely not VRS in my case -- and doesn't sound like that applies here either. My present theory is that this may be a bug in the new RTH function of the low battery warning system. My initial tests seem to confirm this after disabling Go-Home (Advanced ยป Battery), but I'm not making a definitive statement as this point.
     
  10. jetlag

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    I have a new Phantom vision 2+ with seven flights. No prop guards, just like it came out of the box. I have taken mine very high and pulled the throttle/ collective stick all the way back and watched with zero issues. it may be the new software, but it comes down fairly slowly.
     
  11. Wedeliver

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    I have a question, could you have pulled down on the left stick and shut off the props. If you hold the left stick down all the way for like 3 seconds it will turn off the props. When I hear uncontrolled descent, I first want to check and see if the motors were louder then normal, which might indicated VRS as the quad trys very hard to stay up or did the sound of the motors become much less?
     
  12. rrmccabe

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    I have descended over a minute at a time with left stick fully down.. many times. This will not shut off motors with current firmware.