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Kp-index - important or myth?

Discussion in 'General Discussion' started by Drone Camera Films, Mar 19, 2015.

  1. Drone Camera Films

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    I've been working on the principle that the Kp-index is an important pre-flight check and that anything higher than 4 could interrupt the GPS signal, and that it could explain some of the flyaways, but others are now saying that it doesn't make any difference and that they wish people would stop drawing attention to it.

    • Does the Kp-index make any difference to the GPS signal?
      Did it previously but doesn't now because of firmware upgrades?
      Does it/did it only affect certain DJI models?
      Does it/did it only affect Phantoms?
      Have DJI every made any official announcement about it?
     
  2. ianwood

    ianwood Taco Wrangler
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    It affects GPS accuracy. 7 or higher is where you should be a little careful. Unless you're at the North Pole, 4 will do nothing.
     
  3. Drone Camera Films

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    Thanks, and presumably since the Kp-index measure the strength of magnetic storms then it might adversely affect the compass even if you have 7 or more satellites?
     
  4. GoodnNuff

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    The past few days I've driven quite a bit around the Puget Sound area helping with some facility inspections, and my car's GPS has been way off. It would show me driving through open fields or the middle of city blocks where no roads exist. I blame it on the high Kp index.
     
  5. Drone Camera Films

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    Interesting, though it seems the reports and hit and miss. Some people report no problems and others report evidence of effects. I wonder what DJI have to say about it.
     
  6. Meta4

    Meta4 Moderator
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    Most of the people that want to warn others of the potential GPS difficulties have no idea of the real issues.
    (For a lot of users, GPS is a complete mystery and gets blamed for all manner if things it is not related to.)
    Do a google search and about the best you'll find is the vague "gps may be affected" but nothing to say how much.
    Here's a post by a member who actually knows something about what really happens and what the impacts could really be.
    viewtopic.php?f=4&t=35796&p=331319#p331319

    Beware of fear and ignorance. The sky isn't falling.
     
  7. N017RW

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    I understand those who enjoy the minutia of details in things. To each his own.

    Like many, been doing this r/c aviation for decades and all I need to know is: How's the wind, any rain around, and the mosquitoes?!

    Looking at a spread sheet or similar or SV count predictor to decide if I should fly my toy or not is not for me. My P2 does not have telemetry and I can tell if I have enough satellites to know if I can operate w/GPS or not.

    I wish we had answers for some folks' issues we read about here but there's no way to correlate a person's experiences and (often stressed) observations to a root-cause in most cases. Even video of the incident often falls short of a definative explaination so it's usually blame the function(s) or aspect(s) you have the least understanding of.

    If you continue to worship at the alter of GPS signal induced fly-aways please share with us how this happens. It requires an understanding of the Naza's logic flow-chart which I have yet heard or read of.

    Speculators need not apply.