ADSB Traffic Seeing Itself


#1

Having an issue with FlightBox and Foreflight seeing itself as traffic threat. Most times the threat appears very close and at my 4 or 6 o’clock and 200 feet above. I don’t have ADSB Out, but checking to see if there is a way to filter out ownship from the traffic threat alarm.

Please provide the following information:

Hardware:
[  ] FlightBox Kit
[  ] FlightBox Assembled (FB1X)
[  ] Generic Stratux

FlightBox / Stratux version: (e.g. "v0.8r2" or "v1.0r1")

FlightBox / Stratux build: (e.g. "db130aab76")

Radio Configuration:
[  ] Dual Band
[  ] Single Band - US / CA - 978 MHz UAT
[  ] Single Band - International - 1090-ES

GPS Configuration:
[  ] None - Using mobile device's GPS
[  ] Open Flight Solutions Remote GPS
[  ] Internal GPS Module (VK-172)
[  ] Other:

USB Power Source:
[  ] USB Battery: (Make / Model Here)
[  ] Cigarette Lighter Adapter: (Make / Model Here)

USB Cable:
[  ] 3' heavy gauge cable included with FlightBox
[  ] Other: (Make / Model / Description Here)

EFB Application name and version:

Please include a detailed description of your issue or question:


#2

I’m also experiencing ghosting intermittently. Last flight I received 2 traffic advisories of traffic either at my 6 or 9 o’clock and within a quarter mile. Altitude was usually within 200 feet of my altitude. CFI was flying with me and was able to verify that no traffic was within our area. In conversation with other pilots in my community one has suggested that it is my GPS card. I’m running a kit I assembled with dual band configuration and the open flight GPS unit with Foreflight on my non-gps iPad. v1.0 0r1 I believe the build is 945c8bf6bc. Using an Anker USB battery (2nd Gen Astro E3) with supplied USB cable. Appreciate any troubleshooting ideas.


#3

Curt5K,
I can’t believe that we are the only ones having this issue, but I have not seen anything else posted. On a recent flight back from North GA I had several traffic warnings at my 6-8 oclock and 200 feet above my position and less than 1/4 mile. When the traffic appears out of nowhere that close I have come to expect that it’s not real, but nonetheless I’m diligently looking to make sure. On this flight had 3 hours and a copilot to take the stick so when the next threat appeared I reached down and put the transponder in standby to see what would happen. It took 90 seconds but the threat disappeared from my 6 o’clock position and didn’t return, not until I turned the transponder back on and within 60 seconds it again appeared. I also noticed that my transponder is indicating a 200-300’ difference in altitude compared to my Garmin 796 and the iPad. What I believe to be happening is that the transponder is sending out the squawk code with altitude to ATC. ATC is then re broadcasting ADSB information and my FlightBox is receiving the data, comparing it to the position and altitude that it believes it to be at and if not the exact same position reports it as a traffic threat. Thinking the only way to correct this is to go ADSB In/Out as more accurate position reporting and own ship parsing will take place. If anyone has clarity or solution, a reply would be appreciated.


#4

You’re not. It’s an issue with the way ADS-B works. You can find more information on it:

https://www.openflightsolutions.com/ghost-in-the-machine/

There are similar articles on the forums and support pages for all of the major EFBs.