FlightAware Discussions

Aircraft.Json attribute name

Hi,
i´m working for a little project and i work with the Json file from my Raspberry Pi. My problem is that i didn’t really understand some Property/Attribute name, it would be nice if some one could explain that to me.
Here is the Json file:

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The keys are different form the original dump1090 keys… I need to interpret them to…

Any update on this? It would be good to have a definitive description of the new attributes in aircraft.json.

new attributes ?
Is there an update for the Pi?

The definitive description is the source code: https://github.com/flightaware/dump1090/blob/master/net_io.c#L1270

This is really an internal interface so it’s not particularly stable and might change without warning.

For the meanings of the more obscure fields, they generally follow the definitions from DO-260B.

I, too, noticed that the description in the READMEs are not up to date with what dump1090-fa is putting out, so I have done some extensive research in trying to determine JSON field values, and have come up with the following spreadsheet that I’m working on. If anyone knows what the missing values are that I can’t figure out, or notes that I have represented a value wrong, please let me know and I’ll update. That way we have a usable reference.

Excel File - DUMP1090-FA ADS-B Aircraft.JSON Field Descriptions
PDF Version - DUMP1090-FA ADS-B Aircraft.JSON Field Descriptions

By the way, a great reference to what a lot of it means (not all, but a lot – this is the raw data format that gets decoded. dump1090-fa does some…fiddling and magical hand-waving…with the data in the code before it outputs to the JSON. It does NOT output direct messages word for word but takes a bit of an artistic license.)
The 1090MHz Riddle

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Hallo Guys,

it´s been a while for me, had other things on the table than ADS-B…

I started a little comparion between dump1090-mutability, which i am currently using to collect ADS-B data, and dump1090-fa.

The missing fields nav_xyz in the Excel-Sheet provided by @tarsi210 are data from the FMS and/or Autopilot i think, like in this sample:

"hex": "48548c",
"flight": "KLM1993 ",
"alt_baro": 37000,
"alt_geom": 39100,
"gs": 450.2,
"ias": 235,
"tas": 422,
"mach": 0.728,
"track": 102.8,
"track_rate": 0.00,
"roll": 0.0,
"mag_heading": 101.2,
"baro_rate": 0,
"geom_rate": 0,
"squawk": "3173",
"emergency": "none",
"category": "A3",
"nav_qnh": 1013.6,
"nav_altitude_mcp": 37024,
"nav_altitude_fms": 37008,
"nav_modes": [
"autopilot",
"althold",
"tcas"
],
"lat": 51.597709,
"lon": 12.801743,
"nic": 8,
"rc": 186,
"seen_pos": 0.2,
"version": 2,
"nic_baro": 1,
"nac_p": 10,
"nac_v": 2,
"sil": 3,
"sil_type": "perhour",
"gva": 2,
"sda": 2,
"mlat": [],
"tisb": [],
"messages": 1861,
"seen": 0.1,
"rssi": -15.9

dump1090-mutability is much older code and doesn’t decode the ADS-B autopilot / intention messages or the Comm-B equivalents (also things like roll, Mach number)