Recent flights from this feeder, but no tracklog position

FlightAware ADS-B Flight Tracking
1

Sometimes when I check the tracklog for a flight in the “Recent flights with positions from this feeder” on the stats page, there is no tracklog position from me that corresponds to the line in the “Recent flights” table. Should there be or am I misunderstanding the table?

Example:

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I assume this means a position from me, 343 miles away, bearing 143º, 889 seconds ago (around 10:35pm)

But the last position from me in the tracklog is much earlier and only 150 miles away. You can see there are no KAUS positions after this one.

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I’ve only noticed this happen on the occasional flight over ~300mi away. Otherwise the Recent Flights table and tracklogs always appear to match.

Another example:

There is no corresponding KAUS position in the tracklog.
It should be about where this radar position is:

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2

My experience is, if you have had a position used, any positions you send will still show up on the positions from this feeder, even when not used. So if I had a position 20 minutes ago used, I will still send positions and it will show I sent a position 5 minutes ago, even if it is no longer used. Hope that makes sense.

3

That makes sense. I guess I never paid very close attention to it before.

So there are like four levels of positions, each one being a small subset of the one above:

  1. Positions received by dump1090

  2. Positions sent to FA by piaware

  3. Positions used by FA (shown in the “Recent flights with positions from this feeder” table)

  4. Positions that end up in tracklogs