Odd ADS-B / Foreflight issue

Discussion in 'Flight Following' started by Tim Taylor, Sep 17, 2019.

  1. Tim Taylor

    Tim Taylor Filing Flight Plan

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    So I was up an flying around 9AM today when, as I leveled off at 3500 feet, Foreflight called out a traffic warning. My altitude, less than .25 miles at 9 o'clock. No traffic had been seen visually on the climb and visibility was good enough. Scanned the sky and saw nothing.

    About 2 minutes later, another warning same altitude, <.25 miles 1 o'clock. Scan, clearing turns... nothing.

    Finally called up a nearby class D tower to have them see a) if there is anything on radar near me and b) if they can confirm my ADS-B tail number (thinking I was getting an echo of my own plane so maybe I was not transmitting my tail number (?) )

    Tower confirmed my area clear and had me call atlanta approach for ADS-B confirmation. They confirmed tail number transmitting correctly.

    There was a little pucker factor due to the warning but I mostly want it fixed so that false positives don't cause me to not take the traffic warning as background noise.

    ANybody ever run into anything similar?
     
  2. Gwt9678

    Gwt9678 Filing Flight Plan

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    I've had my scout pick my plane up a couple times too. It's always a surprise getting an alert out of nowhere for traffic at same altitude, 0.25nm, 6 o clock!
     
  3. NordicDave

    NordicDave Line Up and Wait

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    This happen from time to time. Something in the system confuses your own ship as a target. I see this on Foreflight but not my 430W.
     
  4. Bill Watson

    Bill Watson Pattern Altitude

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    I get this very occasionally with my Navworx unit (displayed on an exp EFIS). I have not experienced or noticed it with my ForeFlight Sentry system.

    No rhyme or reason and it self clears. Once every 10 - 20 hours or so and gone in minutes.


    Sent from my iPad using Tapatalk Pro
     
  5. Brad Z

    Brad Z En-Route

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    I think this happens when your receiver picks up re transmitted TIS-B data from the ground of your aircraft, but due to some technical issue such as distance from radar (or you're picked up by multiple radars and your position is "averaged") it shows a target far enough away from you that your software doesn't parse it as your own ship. Often times I'll see it and then it just disappears as the software figures out it is "own ship".
     
  6. Tim Taylor

    Tim Taylor Filing Flight Plan

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    Makes sense. Thanks guys!