Using the ADSBX RadarView Tracking Map, I sometimes see two aircraft right on top of each other that are obviously the same physical aircraft, where one has a normal identifier that corresponds to a known tail number and the other is an "anonymous" id (~29xxxx) that shows a tail of "n/a". An example from today, 2021-02-17 at ~13:22 PST (UTC-8), was tail N1120Z (#A03611; source=MLAT, 23 rx) which also appeared as "tail" ~2983A6 (source=TIS-B, 3 rx). Speed and altitude were similar, but not identical. I have screen caps if needed. Are these two different transponders on the same aircraft or is there something else going on? I'll note also that I sometimes see aircraft that you would expect to have a non-anonymous ID and recognized tail number (like LASD helos) show up with only the ~29xxxx anon ID. (BTW, I tried to link ADSBX RadarView Tracking Map to globe dot adsbexchange dot com and it refused the post as being "spam-like". It should probably exempt links to your own site from this filter.)
