Satellite/Compass Reliability?
1593 10 2015-10-21
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jayhkr
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Hey everyone!  Hope everyone is flying well and safe!  Have a question about K-index, satellites and compass reliability.  I've learned to check the K-index before each flight at www.uavforecast.com and today it showed it to be a solid 2 all day.  Low wind, gusts MAYBE to 15mph, partly cloudy, upper 70's, just about perfect!  Took the bird out to my favorite spot and had a great first battery.  Been flying my waypoint missions everweek so I can capture the ever changing foliage in my area so I can make a (hopefully) cool video come time spring.  No issues on my first battery, swapped out to the 2nd battery and just flew around as normal when I get the red "compass error" message and the system automatically switches to ATTI mode.  Of course no one likes it when we're out of GPS signal so I brought her in and struggled just a tiny bit getting her down, nothing big.  My question is what would cause it?  Checked the website on my phone again and K-index still showed 2.  I'm not one to take a chance all the time so I didn't go back up.  Made a phone call within the park I was flying and had a brief connection loss on my phone where the other person couldn't hear me (I heard them just fine though).  So could there had been some sort of cosmo interference for a short time?  Was it something outside the "nature of things", meaning a technical issue?  During the whole flight back in ATTI mode I still showed 15 satellites strong so I couldn't figure out why it lost gps/compass capabilities.  

Fast forward to this evening, I wanted to take the bird up for the sunset as I have yet to capture a REALLY good sunset.  ZERO wind, still partly cloudy, and mid to lower 70's still, again PERFECT!  K-index again showed 2.  Took her up and was going great for 5 or so minutes when I again lost GPS mode, auto switched to ATTI but this time I noticed a TON of sway.  To the point that my heart escalated to OMG mode!  Still got her down safe and sound (this is why I practiced ATTI flying long ago!).  There were a few people where I was with their dogs and after I landed I struck up a conversation and started my "information speil" or "Teaching Mode" if you will to them when they found out I was flying a "drone".  Great people, super curious and excited.  They of course wanted to see it go up again.  Checked the K-index and still showed 2, switched batteries and wanted to show them the automation flying of my waypoints, plus the lighting was perfect to get the trees/sunset.  During the entire waypoint mission not one issue.  Zero, Zilch, Nadda!  So someone tell me what's going on here?  First time out was around 1430 CST, and the second time was around 1800 CST.  I will post the video of that second flight round where the bird was swaying "out of control" and then I will figure out how to post the flight logs for you guys too.  (on IOS and I'm still new to where everything is on it)  Thanks everyone for reading and helping.
2015-10-21
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jayhkr
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Video, best to take your sea sickness pills:


Healthy Drones Log:
http://healthydrones.com/main?fl ... amp;page_id=GENERAL

What else can I post (teach me wise ones) to help out with this?
2015-10-21
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Sir Edward K
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jayhkr Posted at 2015-10-21 20:10
Video, best to take your sea sickness pills:

Glad you were able to handle it and bring it back in.  Did you update to the new GO app and install latest RC firmware?  Just wondering if there is anything new.  Also, do you have a GPS tracker on your bird?  If so where is it located and what kind?

I did not see anything in your healthydrone report other than the notice it switched in and out of GPS mode into Atti mode.  But your GPS signal seemed strong.  It said your compass max was 14.x and noted that all was ok.  But I have not had a compass max that high myself so maybe that is our clue.  The maximum I have had was a 6 something and most of them around 4 something.
One other thing.  You mentioned K index.  I noticed yesterday (not sure what time) my app Magnetology told me that the index went from 2 to 4 I think it was sometime around 5 or 6 Central time.  I think if it will ever ever cause a problem it would be during the time it is flux changing from one to another.  
2015-10-22
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jayhkr
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Sir Edward K Posted at 2015-10-22 05:35
Glad you were able to handle it and bring it back in.  Did you update to the new GO app and install ...

Thank you for the reply Sir Edward. I did not update anything from yesterday's new update. But it was updated a few weeks ago, can't recall exactly what the FW number is, but the latest as of the beginning of October. No tracking device installed. I too thought it was very strange that everything appears to be normal but yet I had all these issues. What about the rocking motion? That scared the life out of me as I've seen other videos of that happening and it doesn't end well at all.
2015-10-22
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Westside Osprey
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Flight distance : 95915 ft
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Does not look normal, I would contact my dealer and/or DJI.

It could be a loose connection or leaky circuit (small intermittent short) on one of the boards. These things can be temperature or vibration induced and are very hard to predict. It happens on all electronic boards sometimes.

I would have it seen to before flying again.
2015-10-22
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imwhitey
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Flight distance : 1921493 ft
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I've read many reports across many forums that the K values will never in any way effect the Phantom.
2015-10-22
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Sir Edward K
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Sir Edward K Posted at 2015-10-22 05:35
Glad you were able to handle it and bring it back in.  Did you update to the new GO app and install ...

I was thinking that rocking (just after the beginning of video) is your compass going out of wack for a second and then coming back.  Maybe the compass has a loose connection.  Even with the little wind you can tell your in atti mode with that drift going on.  That is what makes atti kind of fun in practice.  Good thing it was not windier though with your heart pounding like I can imagine mine would have been would have been a lot harder under that stress.
2015-10-22
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Shon.white
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United States
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don't fly it until you contact dji, mine did the exact same thing three times in about a week
2015-10-22
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Shon.white
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contact dji, on the third time it crashed and was destroyed, also had to switch to atti mode, but like I said, 3rd time charm, i sent it back to dji they are going to repair it for free, but my confidence level in this quad has dropped, i just don't trust it.
2015-10-22
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jayhkr
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United States
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Thanks everyone, I will give them a shout and get the ball rolling I guess!  I appreciate all the feedback.
2015-10-22
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tmygun1
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Flight distance : 2972497 ft
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jayhkr Posted at 2015-10-23 00:05
Thanks everyone, I will give them a shout and get the ball rolling I guess!  I appreciate all the fe ...

Yeah Jay,

If this is the same P3 that you had the signal issues with out in that wide open park, something has to be amiss.

While I know what some of the pitfalls are of using the P3 in GPS mode with a lot of interference, I did a job a couple of weeks ago for a very large maker of snack foods, that shall remain nameless, and I was flying around vats, above ground electrical lines and huge metal mixing silos for a expansion project and the P3 was perfect.......hardest part was the huge wind drafts that came in, over and around the huge buildings and silos.........GPS was flawless.
There has to be some mechanical issue going on because I have read how carefully you prepare before flight.
Good Luck!!

PS - A class B airport  is just a little under a mile from the plant.  I did my due diligence and called the Airport Manager, and after a conversation of 15 minutes he cleared the job with a "Thank You for Checking". He told me it was the first time anyone had ever called the airport with a request to operate a UAV near the facility.  
I found out later that the plant itself has two giant cranes that can be extended vertically 250 feet AND THEY even have to call the airport in advance before they can extend the booms above 200 feet....so the airport can put out a NOTAM.
I can only say that whole experience was very good, especially the convo with the airport manager.
2015-10-23
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