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Vortex Ring state - P3P - things I try to mitigate it...

Discussion in 'Pro/Adv Discussion' started by MoOriginal, Dec 31, 2015.

  1. MoOriginal

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    Ive read the threads about it not really affecting P3P through the anecdotal comments of members here.

    I have a question as to my practice.

    When I descend fast - I always try to put a yaw into the p3 so in other words its spinning as it comes down..
    I just thought that this might help mitigate the wash that im dropping into..
    Im no engineer, so is this not doing anything useful...?

    I also sometimes descend with a slight pitch forward or back - this would help move the p3 out of its wash as it descended.

    Thoughts please from the wise
     
  2. Adil J

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    Rotating it won't do much, however tilting side to side or forward and backward will definitely help!
     
  3. alokbhargava

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    I usually get it straight down or even RTH gets it down straight. I never noticed any issue so far. Lowering down is also a controlled action and P3 doesn't freely drop.
     
    #3 alokbhargava, Dec 31, 2015
    Last edited: Dec 31, 2015
  4. RedHotPoker

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    The canted motors helped eleviate the dreaded death wobble...
    It's a thing of the past, & not a current gremlin.

    RedHotPoker
     
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  5. MoOriginal

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    Can I ask then. What about with propeller guards installed?
     
  6. RedHotPoker

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    You should be fine.
    If you should ever see any wobble just give a little right stick input, and provide the bird some forward travel. There is nothing to be concerned about, just go enjoy...

    RedHotPoker
     
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  7. Jay H

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    If you take a close look at the motors, youll notice that all of the motors are on a tilt. Dji did that on purpose to prevent the VRS.
     
  8. Meta4

    Meta4 Moderator
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    Without prop guards = no problem
    If you feel you have to use prop guards, use a little caution in a fast descent.
    There was a crash last week that sounds a lot like VRS. It was a P3 with prop guards.
    Keeping a little forward motion is the way to avoid this situation - but without guards, it's no worry.
     
  9. RoyVa

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    DJI has put the proper decent speed to help prevent the issue of VRS. Haven't heard of this problem in ages since they coded it in the firmware. The problem was prominent when descending to fast into the prop wash. Slower decent corrected that problem.
     
  10. Mark The Droner

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    When you drive around in your car and you see a pot hole, do you just go over it, or do you try to go around it?

    What happens when you descend through the prop wash is your craft shakes - sometimes fairly violently. But the shaking is invisible through your camera because of your advanced gimbal.

    So you might want to come down at an angle - not because you're worried about a crash but because you don't like running over pot holes.
     
  11. msinger

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    VRS is pretty rare with the Phantom 3, but it's not impossible (see this crash).
     
  12. BigAl07

    BigAl07 Moderator
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    I always try to land with some degree of forward motion even though I have never seen any indication of VRS with the P3. The max decent coded into the FW along with the motors ever so slightly canted seems to almost have eliminated the issue.

    Great information noted above for sure.
     
  13. alokbhargava

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    Where did you read that DJI has reduced the speed to prevent issues of VRS?
     
  14. sbarton

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    I had a VRS crash with my P2V+ when I was coming down and rotating. I would not rotate when coming down. If you don't come straight down (moving forward, backward, or to the side), you aren't going into your prop wash so that helps.
     
  15. alokbhargava

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    Thickness of the prop guards is not enough to stop the back flow of air stream, thus may not produce significant net up thrust.
     
  16. Wibble

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    Prop guards do make VRS worse. I have seen plenty of crashes on Youtube that could have been caused by them.
    VRS is definitely much better on the P3 than the P2. I hardly ever hear the props losing grip anymore.
    This must beg the question - as the tilted props have helped so much how about giving us back a better rate of descent???
     
  17. jingthing

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    Had often wondered why the phantom seemed so slow on decent with the stick down as far as possible.
     
  18. Oso

    Oso

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    I'm hesitant about chaulking that crash up to VRS. For me it just feels like those non OEM props and those big dangling metal clips being used as anti drop pins played more of a role.

    My personal experience is that I do full throttle descents routinely without ever worrying at all about VRS. I'm not saying that a perfect storm of scenarios could never result in VRS with a stock P3, but I am saying I think it would be rare. Same as you advised. Rare but perhaps not impossible.
     
    #18 Oso, Dec 31, 2015
    Last edited: Dec 31, 2015
  19. snowghost

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    VRS because of those props. Unlikely on a stock bird, but there are certain times my P3A is on the cusp of VRS. I've had plenty of practice with it on the X5C, so I know it when I see/hear it.
     
  20. Meta4

    Meta4 Moderator
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    That happened when the P3 was designed.
    The P3 descends 50% faster than the P2 series.