SAR aircraft into BaseStation format

[flygfantast]

I'm using Virtual Radar Server to display my decoded ADS-B aircrafts and a nice feature would be to see SAR AIS-equipped aircraft there.

Would it be possible to add a network output in the BaseStation format for just the AIS messages regarding SAR aircraft?

http://woodair.net/sbs/article/barebones42_socket_data.htm
https://forum.virtualradarserver.co.uk/viewtopic.php?t=360

[jvde-github]

Hello, I don't have any of these tools installed myself so not very familiar but I have seen this request more often. It is technically possible but as the forum discussion highlights not all information in a BaseStation message is available in Message 9 (i.e. planes are identified by MMSI). So, this requires some experimentation on how to map and what works for the receiving software.
In principle the correct route would be to implement AIS MSG 9 functionality in the ADSB plotting software.

Nevertheless, I am more than happy to include this but I need to have some sort of mapping, example or reference implementation as a specification.

[flygfantast]

Unfortunally my knowledge is very slim. I'll try to find some more info.

[flygfantast]

I don't know if it's to any help, but the source code to VRS are on Github: https://github.com/vradarserver/vrs

[jvde-github]

I will add it to the list of things to look at. Thanks!

[flygfantast]

MMSI -> ICAO would easiest be mapped as the last 6 digits from the right. For example MMSI 111265591 -> 265591 (ICAO)

[jvde-github]

Will have a look today. Question, are you running AIS-catcher on Linux?

Do you have a few NMEA AIS lines for a SAR objects that you can share, makes it easier with testing otherwise have to wait until a helicopter is out.

First time I see VRS and it is quite nice!

Some experimentation with Virtual Radar Server shows that this simple format is picked up and shown on the map without confusion with existing planes:

[jvde-github]

Ok, I made a PoC which seems to be working in VRS:

https://github.com/jvde-github/ais2adsb

The program listens to NMEA lines over UDP and sends BaseStation messages to a TCP server like VRS.
If this works well, and has converged to something useful, I can also integrate in AIS-catcher.

This is an example where I also include ships in the BaseStation output (as I was waiting for SAR helicopters):

In principle this should run on both Windows as Linux but requires Python and pyais to be installed.

[flygfantast]

Nice, I will try to get it running on my Windows machine.

[flygfantast]

Got it running without any problems. Unfortunally the traffic is VERY low in the winter at my place, so only stationary sailingships and a basestation in my area. Guess it needs to be moving for the message to be passed on to VRS. Hopefully the military helicopters with AIS transponders will be out tomorrow.

[jvde-github]

Great! I think to make it useful we need to have a good mapping of MMSI codes to ICAO mode S codes. The program already includes a table that was provided to me by another user (who was mentioning good results in VRS for SAR via AIS vs ADS-B so that is encouraging).
If you have any MMSIs for SAR aircraft in your region with corresponding ICAO codes, let me know and I can add.

I also added a standalone package for windows that should be easier to install and run although still requires the command line: https://github.com/jvde-github/ais2adsb/releases/tag/v0.1

ps. did you add 5 parameters on the command line with a 1 as last? This will include AIS msg types 1,2 and 3 in the output. So higher chance of seeing something coming through which might be useful for testing the connection. Class B ship positions are not included in the output.

[flygfantast]

Yes, a mapping feature is great. Unfortunally the ones I have are assigned to military helicopters so no known ICAO is available for them as they never have their Mode-S transponder on.

Yes, I added the last parameter, although I got no positions right now since alt the boats are anchored.

I will give you some NMEA lines later today if the helicopters are out (but it's bad weather today, heavy snow and windy).

[flygfantast]

111265534.txt

Attached is todays traffic from SAR helicopter with MMSI 111265534.

Examples:

!AIVDM,1,1,,A,91b76wP00K15iKPQRrF:Ld0000S:,0*1B
!AIVDM,1,1,,A,91b76wP00M15h0pQRtC:8E000@=p,0*45
!AIVDM,1,1,,A,91b76wP00S175kPQS64=1pP000SC,0*3D
!AIVDM,1,1,,A,91b76wP00c15goPQRv@:opP00@F8,0*2B
!AIVDM,1,1,,A,91b76wP00h15kB@QS3E8wV@000S:,0*1B
!AIVDM,1,1,,A,91b76wP00i177;0QS=6;jsP005bh,0*7D
!AIVDM,1,1,,A,91b76wP00j177J`QS=6;os0008KA,0*37
!AIVDM,1,1,,A,91b76wP00k15kK`QS4791mP008?1,0*47
!AIVDM,1,1,,A,91b76wP00q1786HQRih=hv0005bd,0*79
!AIVDM,1,1,,A,91b76wP00r15fjhQRnL79qP00D01,0*33
!AIVDM,1,1,,A,91b76wP00v16w7HQJh5:gm0000SA,0*77
!AIVDM,1,1,,A,91b76wP012178`hQRT5=Vph005bd,0*4D
!AIVDM,1,1,,A,91b76wP01416o:0QSb0;0h000<02,0*00
!AIVDM,1,1,,A,91b76wP01516dD@QVi>9GM@000S:,0*43
!AIVDM,1,1,,A,91b76wP01716sM0QJnf;TJh000S:,0*52
!AIVDM,1,1,,A,91b76wP01716sq8QJmS;OJ@00HIc,0*58
!AIVDM,1,1,,A,91b76wP017179khQRWV=JVP008AI,0*23

[jvde-github]

Thanks, tested and it worked well. I read in your file and send it to ais2adsb using the following command:

AIS-catcher -r txt 111265534.txt -u 192.168.1.235 4005

And send it as ADSB msg to VRS as follows:

ais2adsb 192.168.1.235 4005 192.168.1.239 30003

and it shows up in VRS (!!!):

Test passed. Many thanks for sharing.

[flygfantast]

Gr8 ;)

[flygfantast]

111265103 = 4AB423 (SE-MAC, Swedish Coast Guard KBV503)

[jvde-github]

Thanks I have added it to the ais2adsb default list.