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strange sudden up movement when landing manualy

Discussion in 'Pro/Adv Discussion' started by cypher007, May 26, 2016.

  1. cypher007

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    might be a noob question but when landing my p3p manually it will sometimes suddenly gain height when im about 1ft from the ground, almost as if it is fighting me to land. im in p mode.
     
  2. Oso

    Oso

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    Sounds like VPS or updraft.
     
  3. cypher007

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    blimy that was quick. realised ive spelt the title wrong but cant edit it, I blame the wine.

    anyway don't think its an updraft as the motors suddenly pulse. could be vps and im guessing this is the cause.
     
  4. flyNfrank

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    It's the barometer sensor that is responsible for this. Called Pogo-ing.
     
  5. Mark The Droner

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    +1

    Yes - the air pressure increases dramatically as you come close to the surface because the props are blowing air down onto the ground and it's hitting the ground and coming back up. So the increased air pressure makes the craft "think" it has suddenly dropped too much and compensates.
     
  6. Multicoptertec

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    Could also be your stick handling. There is quite a bit of prop wash downward. Try being a little more deliberate with left stick down. Hold left stick straight down for 3 seconds to stop the motors once you have landed.
     
  7. Digdat0

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    I'd disable VPS, see if it still occurs. What are you landing on? Grass, concrete, etc?
     
  8. N017RW

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    Without seeing this it's hard to really evaluate.
    I don't give much creedance to any of the barometer based guesses. In an otherwise normally functioning aircraft when you command the craft down it should continue to do so despite the Barometer.
    My first thought is Ground Effect. Simply put... additional lift created by proximity to the ground.
    It may also be your technique. Again without witnessing it it's hard to evaluate with certainty.
     
  9. Roamer105

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    Yes, I have experienced this with my P3P several times. Mostly it happened when approaching the ground very slowly hovering to focus in on the exact landing spot, then just as I pull back to land, it quickly "hops" up maybe a foot or so prior to comply with my pulling back the throttle.
    I thought it might have to do with the VPS, but the barometer theory sounds more plausible.



    Sent from my iPad using PhantomPilots mobile app
     
  10. Leenanj

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    Haha, that wine can also effect landings.

    But I agree mine does that to if you come down to fast, turning off VPS usually helps eliminate it.
     
  11. N017RW

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    Ahh. I see I overlooked the motor pulsing aspect. VPS is a serious consideration.
     
  12. Wibble

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    I have never experienced this becuase I always hand catch. It is much easier!
     
  13. alokbhargava

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    Usually I hand catch it but whenever I land on ground, I use a flat board and never noticed upward sudden movement. There is definitely some ground effect but notice alarming.