Add support for AIS message 9

The "to-do" list for Virtual Radar Server is as long as my arm, but if you want to pile more work onto it then this is for you.
Skibox
Posts: 148
Joined: Mon Apr 07, 2014 7:06 pm
Location: ESGG

Add support for AIS message 9

Post by Skibox » Thu Apr 10, 2014 2:40 am

A nice addition would be tracking of AIS-equipped SAR helis and fixed wing AC. Many of these do not transmit position on 1090, and often fly so low that MLAT s very difficult. But they transmit full position incl altitude on the AIS system using message 9 (SAR Air).

Most UK SAR helis seem to have AIS now and the Swedish have had it for many years.

http://www.transmission1.co.uk/viewtopi ... 0&p=228140

Suggestion: Add a feed option for AIS, decode the messages that are aircraft. They look like this:

!AIVDM,1,1,,A,91b76uh00012OhhQO52=;UP00<03,0*09

I can provide more info and test data if there is interest.
Screen shot 2014-04-10 at 03.37.40.png
Screen shot 2014-04-10 at 03.37.40.png (79.46 KiB) Viewed 8204 times

/M

Mac
Posts: 84
Joined: Tue Mar 19, 2013 11:49 am

Re: Add support for AIS message 9

Post by Mac » Thu Apr 10, 2014 10:32 am

This would be a brilliant addition. My interest is mostly SAR also. I have my own AIS server and can also provide test data if needed.

Mac
Posts: 84
Joined: Tue Mar 19, 2013 11:49 am

Re: Add support for AIS message 9

Post by Mac » Thu Apr 10, 2014 10:56 am

An alternative ( Possibly less work ) would be if a Google AIS map could be merged with the VRS map.
I have a map http://www.airwavesireland.com/ais/int.html showing AIS data.

It might be possible to merge or overlay this map onto another ?

Thanks

jonfear
Posts: 365
Joined: Sat Feb 09, 2013 12:15 pm
Location: Wick St Lawrence
Contact:

Re: Add support for AIS message 9

Post by jonfear » Thu Apr 10, 2014 11:47 am

And to add to the interest there maybe a Raspberry Pi solution for a data feed as well...

http://forum.aishub.net/ais-decoder/ais ... a-release/

I will give this a go when I get my spare Pi...

Jon
http://www.360radar.co.uk, the new name for MLAT Radar in the UK and Western Europe.

Former PP feeder Bm. No longer feeding. I do not have time to sort out imaginary problems with NTP
when it has been working fine for 2+ Years.

agw
Posts: 2241
Joined: Fri Feb 17, 2012 3:20 am

Re: Add support for AIS message 9

Post by agw » Fri Apr 11, 2014 1:22 am

I'll add it to the list, but before it can be done there'd need to be work done on mapping whatever identifier these aircraft transmit on AIS messages to ICAO codes.

Mac
Posts: 84
Joined: Tue Mar 19, 2013 11:49 am

Re: Add support for AIS message 9

Post by Mac » Fri Apr 11, 2014 9:31 pm

I don't think they use ICAO codes in the message.
Could be wrong though

Skibox
Posts: 148
Joined: Mon Apr 07, 2014 7:06 pm
Location: ESGG

Re: Add support for AIS message 9

Post by Skibox » Sat Apr 12, 2014 2:42 am

agw wrote:I'll add it to the list, but before it can be done there'd need to be work done on mapping whatever identifier these aircraft transmit on AIS messages to ICAO codes.
That is true. AIS uses a similar system of unique identifier codes called MMSI, Maritme Mobile Ship Identifier. It's a 9-position decimal number with 3 positions used for country codes. A ship has numbers CCCXXXXXX where CCC is the country of registry. Some transmitters that are not normal ships have special prefixes, and aircraft use 111CCCXXX. In my picture above 265 is one of the country codes for Sweden.

Mapping MMSI to ICAO must be done manually, like editing routes, there is no systematic relationship. That should be relatively easy, there's not that many SAR units in any given country and they seem quite static. It's more of a problem what to do about MMSIs with unknown or even unassigned ICAO codes. Is there a "reserved" series of ICAOs that could be used as temporary or "bogus" (calculated from MMSI) codes?


/M

agw
Posts: 2241
Joined: Fri Feb 17, 2012 3:20 am

Re: Add support for AIS message 9

Post by agw » Mon Apr 14, 2014 1:28 am

I'd have thought that all aircraft would have an ICAO code so that they'd show up on secondary radar? There are blocks of ICAO codes that aren't currently allocated but I'm not sure whether there are any that will never be allocated (except perhaps for 000000 and maybe FFFFFF).

Skibox
Posts: 148
Joined: Mon Apr 07, 2014 7:06 pm
Location: ESGG

Re: Add support for AIS message 9

Post by Skibox » Mon May 05, 2014 10:32 pm

agw wrote:I'd have thought that all aircraft would have an ICAO code so that they'd show up on secondary radar?
Well, not necessarily. Many regions are still relying on mode A/C and lot's of aircraft have no mode-s transponders, and therefor does not need a ICAO code. But I saw that the UK registry assigns codes whether the aircraft needs it or not. I asked the swedish registry about their policy and it's basically the same. They also informed that the ICAO code for all new and most existing swedish a/c is based on an algorithm to calculate ICAO from the registry letter. SE-ABC will have a ICAO code from converting ABC and adding the swedish ICAO country prefix.

There are also ICAO codes assigned to military SAR helos, problem is just finding them...

That only leaves one type of SAR-MMSIs as a problem, and that is a kind of mobile units we have when the Volunteer Air Corps flies SAR/Surveillance in small general aviation planes. There is no fixed connection between MMSI and regsistry, so there we would need some form of un-assigned ICAO to map to.

/M

9Aplus
Posts: 1
Joined: Fri Nov 13, 2015 1:52 pm

Re: Add support for AIS message 9

Post by 9Aplus » Mon Nov 16, 2015 2:21 pm

Just like to say hello ;)

and to ask in case of any progress regarding AIS?

I am feeding FR24 since 2013. and now have just
signed the deal with vesseltracker.com
with option of possible local data use.

My goal is to have both layers of local data present on map.
Regards
Dj

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