Introducing MLAT Beta Testing!

Due to FlightAware’s decision to start “filtering” some aircraft from their MLAT feeds, ADSBexchange has started a beta test to calculate our own MLAT positions.  For more information on how to participate, check here:

32 thoughts on “Introducing MLAT Beta Testing!

  1. Both Flightaware & Adsbexchange MLAT inputs were fed to port 30104.
    In order to independently watch MLAT feed from Adsbexchange, I directed the MLAT feed of adsbexchange to VRS on my Desktop by editing the file “” and changed following part:
    –results beast,connect,
    –results beast,connect,192.168.xx.xx:30104
    where 192.168.xx.xx is Local IP of my Windows Desktop running VRS

    Here are screenshots of VRS showing how it was done:




    1. “Both Flightaware & Adsbexchange MLAT inputs were fed to port 30104.”

      I’ve been using port 30106 for FA’s MLAT feedback. If adsbexchange is using 30104 it shouldn’t be a problem. Or am I missing something here?

      My set up is a dedicated RPi 2 with FR24, FA and adsbexchange feeders. Have VRS running on a remote computer with database editor plugin to edit VRS’s a/c data for my own use only.

      Haven’t installed the MLAT for adsbexchange yet but will it work ok parallel to FR24 and FA?
      Not surprising that FA is blocking some MLAT data, I thought they were doing that all along.
      Thanks for getting MLAT going on adsbexchange and look forward to participating

  2. “Due to FlightAware’s decision to start “filtering” some aircraft from their MLAT feeds”

    How has this affected, or how will it affect the ability to track military aircraft via this site?

  3. FlightAware is filtering some undisclosed list of aircraft from their site. It would appear, for example, that Air Force 1 is on this list. Most military aircraft are not filtered from MLAT results returned to participants by FlightAware right now however.

    ADSBexchange is not filtering anything. The best way to ensure all possible planes show up here is to participate in our MLAT feeds.

    Clear as mud?

  4. Hello all, I found ADSBExchange by accident, and out of frustration that sites that I feed to, block information on some aircraft. I was following a discussion on FlightAware that referenced “that other site”, and thought… Well, that “other site” sounds like exactly what I am looking for.

    Anyway, I have a remote Pi, running PiAware 2.1-5 and I ran the scripts according to the instructions provided. All seemed to go well upon reboot, and I see the processes for feeding data to you running. However, I do not see my feed in the Sync Grid. (tdhart-02). I am also feeding from VRS from my local location (running PP here, but if there is enough interest in having another MLAT location for your service, I’d consider throwing another Pi into play… For a total of two in north LA County, 36 miles apart). Anyway, the instructions seemed to indicate that the feed should show in Sync within a few minutes, it has now been over 12 hours. Perhaps the MLAT Beta has reached its current capacity?


    1. I should add that the remote site is currently successfully feeding FA MLAT and ADSB etc. So I know it it at least sending to them. The other possibility…. Perhaps the scripts don’t work with PiAware 2.1-5?

  5. I’m seeing some unusual flight tracks when the default adsbexchange-mlat ports are used. I originally thought this was a Flightaware issue with mlat, but it turns out to only happen when I’m also feeding adsbexchange-mlat. The results come back to port 3014, same as FA. So I think this means that the dump1090-fa sees them and displays them on the map. here’s what I mean:
    I’d like the adsbexchange-mlat results plotted on the dump1090-fa plot, just not like this! FYI, Piaware 3.0.4. Any ideas?

    1. Ok, you can turn off feeding the MLAT results back into your dump1090 map, or send them to a different port by editing the file… Change the -results parameter.

      1. Thanks Dan. I sent the mlat results to a different port and these funny tracks disappear. But, of course, I don’t get to see the adsbexchange mlat tracks on the map either. Interestingly, when I checked a few of these funny tracks on your site, the track didn’t start until the path became stable. I wonder if there is some way to not return mlat results until they stop bouncing around? Thanks again for all the work you do on this project.

  6. I’m using Rpi 2 with jessie 8 o/s. Build from scratch. The only things installed are Piaware, FR24feed and adsbexchange feeder. All were installed one at a time, no so called “SD images” from either FA or FR24. Is there a new forum support page for installing adsbexchange MLAT ? I would like to see the success of others who followed known instructions before I attempt it myself. I have a working rpi that’s mounted right next to the antenna and it’s a pain to get to the SD card to replace it. It’s harder to backup the ssd card than it is just to start over again. TIA :).

      1. Or, if you have MLAT-client installed on your Pi, you can just run that with a babysitting script to keep it running. You can compile it from source off of github…

  7. Success! I followed the instructions here and I’m already showing up in the stats page and on the feeder map. Everything still works fine with FA, FR24 and my PC’s local VRS. Added a VRS receiver for port 30104 to receive mlat data back from adsbexchange. So far it’s very lonely but it looks more receivers are popping up in my area.

    To anyone installing this on a working feeder that is up to date with dump1090mutability 1.15, since I had a fully working pi with FR24, FA and adsbexchange already working, I took the option about half way down the page and opted out of re-installing anything that was already installed. Only checked the option for adsbexchange install (which was the last on the list and not the default so be careful when you get to that step). Took about an hour to install but seems to be working ok.

    The link:

    Start here if you have a fulling working rpi with other feeders (the following quoted from the website):
    “If you wish to install the software on another operating system or your own Raspbian image run the following commands from the command line.

    sudo apt-get update
    sudo apt-get install git
    git clone
    cd ~/adsb-receiver
    chmod +x

  8. One of my receivers was connecting 2 days ago to the MLAT servers but no longer does. Are there logs that I can look at ? (the receiver name is fly_zulu-02)


    1. fly_zulu, you see you’re MLAT synch stats here:
      If you’re the same fly_zulu with 2 feeders in the KSJC area, I show regular synch with your feeders. Are both configured with accurate location coordinates? I’m showing you synched with my feeder (KSJC) right now as fly_zulu-01.

  9. My co-ordinates look good. I was connected for a while earlier this morning and could see synched with you feeder. Had to restart my RPi and now it sitting in this loop again :

    Tue Sep 13 09:29:19 2016 Reconnecting in 30.0 seconds
    Tue Sep 13 09:29:50 2016 Connected to multilateration server at, handshaking
    Tue Sep 13 09:29:55 2016 Lost connection to
    Tue Sep 13 09:29:55 2016 Reconnecting in 30.0 seconds
    Tue Sep 13 09:30:25 2016 Connected to multilateration server at, handshaking
    Tue Sep 13 09:30:31 2016 Lost connection to
    Tue Sep 13 09:30:31 2016 Reconnecting in 30.0 seconds
    Tue Sep 13 09:31:01 2016 Connected to multilateration server at, handshaking

    Maybe there are a limited number of server connections available in this beta.

    1. Yes, in fact there was a limit of 100. I just upped it. Thanks for letting me know. Shortly, I am moving the MLAT server to a more powerful CPU and will be adding additional MLAT instances.

  10. Hi Dan,
    Here the same problem:
    503 Service Unavailable
    No server is available to handle this request.
    Log file:
    Wed Sep 14 15:29:38 2016 Connected to multilateration server at, handshaking
    Wed Sep 14 15:29:50 2016 Lost connection to
    Thanks for your attention.

  11. Dan, problem solved, thank you. Now I see in the log:
    Wed Sep 14 15:45:02 2016 Handshake complete.
    Wed Sep 14 15:45:02 2016 Compression: zlib2
    Wed Sep 14 15:45:02 2016 UDP transport: disabled
    Wed Sep 14 15:45:02 2016 Split sync: disabled
    Wed Sep 14 15:45:02 2016 Input connected to localhost:30005
    Wed Sep 14 15:45:02 2016 Input format changed to BEAST, 12MHz clock
    Wed Sep 14 15:58:59 2016 Receiver status: connected
    Wed Sep 14 15:58:59 2016 Server status: ready
    Wed Sep 14 15:58:59 2016 Receiver: 1539.6 msg/s received 251.0 msg/s processed (16%)
    Wed Sep 14 15:58:59 2016 Server: 0.1 kB/s from server 3.0kB/s TCP to server 0.0kB/s UDP to server
    Wed Sep 14 15:58:59 2016 Results: 99.3 positions/minute
    Wed Sep 14 15:58:59 2016 Aircraft: 19 of 52 Mode S, 55 of 90 ADS-B used

    At the moment the page “” is static here, I can’t navigate in it. I don’t know if this is a known problem for you.

    Success with the further development,

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