Dump1090 Display

When using the Dump1090 display, I will occasionally (not rare/not frequent) have a flight that does not display the live track but does display the full suite of statistics with 0-1 second updates for the complete data suite (- squawk). It will invariably have a flightaware link to a flight that was apparently not closed (on taxiway, yesterday, or whatever).

I can understand the bad link data but wonder why the live track does not display. I thought the live map was independent of any external input.

A full suite including position? I don’t know of a way for dump1090 to know the position but not have a track displayed for it.

A Mode S only flight will show squawk/altitude/ident but not position.

The local dump1090 map is indeed entirely independent of FA’s tracking - it is fed direct from your local receiver only.

I will capture an image the next time I see it happen. I get the ICAO, Flight, Altitude, Speed, Track, Mags & Seen with the mags and seen updating steady but no map display of that specific aircraft

That sounds like a Mode S transponder.
Or actually possibly an ADS-B transponder that is not providing position info, only the velocity messages (yes they sometimes do this).
Or even an ADS-B transponder that is producing completely bogus position data so dump1090 is throwing it away.

Been watching the occurrences and think it is probably a switch or some such thing the crew is missing. Always is the new Sukhoi Superjet 100 which I would think would have the latest avionics.