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Mid-flight scare 1 mile offshore

Discussion in 'Pro/Adv Discussion' started by silverstoned83, Jun 20, 2015.

  1. silverstoned83

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    I'm hoping someone can help me understand why my Phantom behaved the way it did during my last flight. You'll see at 1:17 in the video where my gimbal makes a strange movement suddenly. I thought for a second that a prop came off! :eek: Of course it happens for the first time while I'm over a mile off shore..

    I would have liked to get some better shots of the ferry, but I took too long to launch because my compass was detecting abnormal conditions. All was fine after calibrating the compass. I'm wondering if there might have been HV power lines buried directly under where I was launching from. My previous compass calibration was done only a few miles away.

     
    dalebb and dwcola like this.
  2. delirious

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    If the wind was blowing and you were moving lateral. The gimbal will do that.
     
  3. Adam Kontras

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    Looks like a compass issue. That's not a normal gimbal movement even in INTENSE winds.
     
  4. Panotaker

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    Those light poles where you are standing are getting fed by underground cables, so that might have something to do with your compass. Plus that concrete wall probably has a lot of rebar in it.
     
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  5. silverstoned83

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    So is it ever advisable to ignore the abnormal compass warning and fly anyway? I'm assuming my previously saved calibration was solid as I've never experienced this issue, even in windy conditions. The winds were calm that evening.
     
  6. amused2deth

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    I recalibrate the compass every time I fly. I make sure I'm at least 6 feet from anything other than dirt or asphalt. I panic when the video flickers on my phone so I don't push limits. Paranoid? No, I still fly it. I just don't push it with all these problems being posted. So me personally I would calibrate every time and stand clear of any metal or cement barricades. Just me though.

    Sent from my SM-N910T using Tapatalk
     
  7. Kman

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    I never recalibrate unless I am 100 or more miles from my last calibration location.
     
  8. suck it up

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    Wind, believe me, it is the wind...........
     
  9. Buckaye

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    That's weird movement to be sure... That doesn't look like wind to me... It looks like brief power outages to the gimbal or something like that... The gimbal looks like it is going slack and then catching again
     
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  10. storrowdrive

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    I think you nailed it there from the way it looks.
     
  11. Oso

    Oso

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    You guys make such nice videos. I feel so inadequate.

    To me it looks like something either hit the gimbal (bird or large insect?), that it was snagged on something briefly (loose ribbon cable?) or had something (grain of sand?) in the mechanism. and then it reoriented itself.

    I don't think it was wind.
     
  12. herby

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    Mine did the exact same thing while flying in 15-20 mph winds while trying to capture wind turbines. It did it once and hasn't done it since.


    Sent from my iPad using Tapatalk
     
  13. silverstoned83

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    Thanks for the kind words. I find the matching the music for the video makes a big difference. I spent hardly any time editing it.

    The possible causes all sound plausible. It at least makes me feel better that someone else has experienced it without anything bad happening afterwards. I'll just find a better place to calibrate everything prior to launch from now on.
     
  14. Oso

    Oso

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    Hey man, I read a single post in another thread which made me go look at my gimbal. It occurred to me that this could potentially be what your gimbal was momentarily snagged on in the video. It's worth a look just in case.

    http://www.phantompilots.com/posts/425939/
     
    #14 Oso, Jun 24, 2015
    Last edited: Jun 24, 2015
  15. leekiya

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    It wont have been a compass issue, taking of from metal or a sea wall with rebar might cause one yes and cause the craft to flick into p atti, but once you flew away from it gps would have returned.
     
  16. eliomartin

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    Calibrate the IMU and see to.
     
  17. ianwood

    ianwood Taco Wrangler
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    No. It's a sign that something is wrong.

    Calibrating every time is a bad idea. So is asphalt.

    For everyone, the compass needs a magnetically clean calibration and a magnetically clean take off point. If either of those are in the presence of magnetic interference, your flight could end in a bad way.
     
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  18. Mal_PV2_Ireland

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    Clair de Lune beautiful tune. I wouldn't have worried too much after seeing that glitch in the gimbal, of course it shouldn't happen but I'd just calibrate everything and carry on flying. Just keep an eye out for it but you probably won't see it again.
     
  19. amused2deth

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    So should I start taking off on the hard case?

    Sent from my SM-N910T using Tapatalk
     
  20. MattyDread

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    Can you please explain why calibrating every time is a bad idea.

    I'm sure I've read elsewhere to calibrate every time you fly in a different location (even 50ft - 50miles away)

    Thanks