FlightAware Discussions

MLAT error, or what is wrong?

Have a look at this screenshot - The “plane” has been on my radar for over 30 minuttes, is it MLAT calculations going wrong? It’s way past my range.

VRS shows it to be 110 nm away, where PiAware and TAR1090 shows the 450 nm. Malformatted messages, testsignal or what happen.

I doubt there is much analysis possible here unless you captured the raw position messages at the time. It might be a CPR decode error where it picked the wrong cell. What mlat data source are you using?

Thanks… It’s still on my radar. Any way to get the raw data at ease? Won’t spend days figuring it out :slight_smile:

view1090-fa --no-interactive --show-only (ICAO address in hex) 2>&1 | tee capture.txt

I’d say the ICAO is being used by more than one aircraft?
(looks to me like the international VFR squawk 7000 was also entered as ICAO hex id
https://en.wikipedia.org/wiki/Aviation_transponder_interrogation_modes#ICAO_24-bit_address)

And/or it’s intermittently sending bad ADS-B positions and then being located by MLAT again?
Could be lots of stuff … hard to analyze.

Yeah after looking at it a bit … think it’s just two aircraft using the same hex.

With my luck, the “plane” was gone when i saw how to capture raw data…

If it happens again, i’ll try to capture some data…

Thanks for replies. :slight_smile: