Web Interface Live Data

Newbie question: I see a lot of ICAO codes but many of them don’t have a flight number. Are those MLAT entries or missing data. Also, I see some people have MLAT syncronized with xx nearby receivers. How does one do that? Thanks!

From your stats page you are feeding MLAT data, but in order to see them on your local interface you need to be running DUMP1090-MUTABILITY, not the version of dump1090 used on the Flightaware PI image.

MLAT will synchronize with nearby receivers automatically when you all detect the same aircraft. So you need to have decent aircraft traffic and enough receivers nearby to sync with. You can how many you’ve synced with in the log (/tmp/piaware.log, or the log pane on your stats page)

You’re right many of them won’t show a flight number in dump1090. The local interface only gets a flight number/callsign if the aircraft sends it (and many don’t). For now when you select a plane you can click on the ICAO hex link at the top to look it up at airframes.org

There are some flights which transmit only the bare minimum data required under Mode S, which is ICAO and altitude. Since the ATC knows all the numbers and is actively probing the transponder using a rotary antenna, this response is sufficient for their system to identify the flight and locate the aircraft in 3D space. By using MLAT, a network of passive observers such as us can locate the lat/lon of the transmitter. For us to know any further details about the flight will requre checking an external database.