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Upward Drift in GPS

Discussion in 'Phantom 2 Vision Discussion' started by ShawnSmith, Feb 14, 2014.

  1. ShawnSmith

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    Last weekend I pushed all of the current updates to my P2V. Took her outside to my usual practice field and flew two full batteries in GPS and a little in ATT mode. Had no issues at all. Then I loaded her up, got on a plane and flew to South Carolina(about 4 states away). I was near the coast and a large industrial park. As soon as I started the P2V my phone app demanded a compass calibration. I did the dance. I originally tried to take off on a large concrete slab but was not able to get any satellites at all while on this slab. So I moved to grassy clearing a few hundred feet away. I got 7 satellites and lock looked good. I put her in the air about 10 feet for pre-flight check, immediately she began to drift to the right and upward gaining altitude very quickly towards some trees. I fought her down to land, it wasn't pretty but not too hard. Tipped over and broke two blades. I replaced the blades and did the dance again... exact same results(two more blades down). A little later I went to a completely different location and took off in ATT, she was stable aside from wind drift(but manageable). I put her up in the air about 100 feet and switched to GPS, had about 9 satellites. Seemed to hold okay, but appeared to be making very strong adjustments with hands off the controls. Had to land in ATT because GPS did not feel right. I am back home now, I did an advanced re-calibration in assistant and did the dance. I did a test flight here where I have in the past flown several times without issue and am seeing the same upward drift now. Something appears off with GPS but basic calibration and advanced in assistant don't seem to help. I am at a loss. Help would be greatly appreciated.
     
  2. Pull_Up

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    Upward drift implies a problem with the barometer. When you flew did the aircraft go carry in or in the hold?
     
  3. ShawnSmith

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    I had to check the go pro case with the P2V. So it flew in the hold with all the other luggage. Case is very secure though. It has traveled with me a on a plane few times before without any issue.
     
  4. Pull_Up

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    Hmmm, just wondering if the pressure changes during the flight might have done something to the baro. But plenty of others fly with their aircraft and I haven't seen any other post-air travel issues like this reported...
     
  5. ShawnSmith

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    I am certain that aftermarket blades were the cause of this. I put on some old DJI blades and the problem was gone. Watch out for these blades.
    viewtopic.php?f=19&t=8820
     
  6. Kelso Kubat

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    i took of my gimbal and flew with the factory settings and noticed a similar jolting motion upwards. quick little bursts of upwards drift. i narrowed the issue to be a combination of wind/lack of experience flying/ and the gimbal being off. the crafts settings of 200% work fine if there is the extra weight of the gimbal calculated in. without the gimbal at the craft was light. with the gimbal back on it feels smoother. less jolty. :shock: