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Parked Aircraft

Posted: Fri Sep 27, 2024 8:03 am
by Harrier77
Hi,

There is an ongoing discussion in the PSXT forum about the parked aircraft at airports generated by RTv4 data. It has been observed that when PSXT starts and parks aircraft (using RT data only) not all aircraft that have arrived at the airport within the last 24 hours and are still present in real life, are showing up (sometimes only a fraction of the aircraft that should be present are parked). Nico has said that the issue is not with PSXT, but with the data from RT.

The PSXT release notes state that improvements in the RT data about parked aircraft are expected, so the question is are you looking at the issue and when might we see these improvements?

Peter

Re: Parked Aircraft

Posted: Fri Sep 27, 2024 10:25 am
by admin
Hi Peter,

thanks for bringing this to my attention. I am indeed working on improving the parked aircraft algorithm. This is a relatively slow (and iterative) process, taking several days to cross check the improvements, if any.

There’s always the problem of what data to compare it against. What’s the “ground truth” you compare the RT data with?

I’ve had feedback from spotters that say the parked aircraft coverage is nearly perfect for e.g. EGLL, but at other airports it can be problematic, either because the ADS-B coverage on the ground is spotty, or because aircraft on the ground are moved around by technical crews, and they don’t always switch on the transponder when moving them - that makes it impossible for RT to detect when a gate is empty.

PSXT has some smarts built in that won’t double occupy a gate, I’m not sure how Nico is doing that, as with the data I have that can’t reliably be done (some gates are so close together that an aircraft position can be a match for either). So the RT data as PSXT receives it requires some additional processing.

Hope this helps shed some light into the complexity of this.

Re: Parked Aircraft

Posted: Fri Sep 27, 2024 11:23 am
by Harrier77
Hi,

Thank you for the explanation, I hope you find a way of improving the parked aircraft situation.

The airports at which I have found the issue most in testing are EGCC and EGPH, both with good RT coverage. First thing in the morning, before the first wave departs, only about 60% of the actual aircraft at the airports are shown in PSXT. Try them at about 0545 UTC and you will see what I mean.

Anyway, what we have now is good as far as it goes, hopefully getting better soon.

Peter

Re: Parked Aircraft

Posted: Fri Sep 27, 2024 11:45 am
by Harrier77
"There’s always the problem of what data to compare it against. What’s the “ground truth” you compare the RT data with?"

I use FR24 data to see what aircraft are at an airport.

Re: Parked Aircraft

Posted: Sat Sep 28, 2024 11:39 am
by Nico Kaan
Harrier77 wrote: Fri Sep 27, 2024 11:45 am I use FR24 data to see what aircraft are at an airport.
RT has similar data; FR24 is also based on ADS-B data. FR24 does not have to tell whether an aircraft is parked at a gate or not, if so FR24 would have the same problems as RT...

Re: Parked Aircraft

Posted: Sat Sep 28, 2024 2:15 pm
by Harrier77
I understand all this. What FR24 does provide is a list of the aircraft currently at the airport including details of aircraft type, airline, etc. This information allows a comparison with what RT provides, and in my experience shows that RT is not currently parking all the aircraft that are at an airport.