Satellite AIS?

Kelpie

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Apparently you can pay a subscription and receive AIS from vessels offshore, which is picked up by satellites.
I know this works for big commercial ships (class A?)
Will it work for our little Class B/B+ units?
 
I see MarineTraffic are showing these more often recently, looked at the cost though of adding option and it appears to be per boat that you preselect like on your favourite fleet option. They seem to be moving more to these when I’ve looked when before they would be on standard view, marketing ploy perhaps?
 
IMHO, normal VHF-based AIS is perfectly adequate for showing your position to other, similarly equipped vessels and for ascertaining theirs, in real time. All other options are either for remote tracking of ocean-going commercial vessels and yachts on long offshore voyages, or are non-essential 'toys', not for serious navigational use.
 
If you want to get tracked across the ocean, it's an option on both Garmin inreach and Iridium Go.
Yup aware of this options, just wondering if my existing equipment might be picked up as well.

I'm actually asking on behalf of a relative who would like to keep tabs on us from ashore.
 
This was the reason, that SOTDMA (B+) was intoduced). The Satellite's pick Up the AIS traffic.
Thanks, that is exactly what I was hoping. We've just got (yet to install) an Onwa 708A which has B+.
Should keep the people back home happy when we're crossing Biscay later this year.
 
For Class B, satellite AIS is not that reliable, meaning there are long periods during which the signal is not picked up, long periods sometimes means "days".
We noticed that while following Imocas, some of them had classB transponders (not sure if CSTDMA or SOTDMA, lower or higher power), they were tracked on Marinetraffic, actually MT just showed "pleasure vessel" -without subscription they will not let you know where is the specific boat you are looking for- but if you know one boat or a group of boat is in a specific position then you may infer the one on MT is the one you are looking for.
The OCC asked a price to follow a fleet and the per-boat fee would still be very very high.
I would not use satellite AIS: imagine someone on land seeing the signal disappear for one-two or more days... You may explain beforehand that technical problems might prevent the signal from being regular, but once it happens people on land immediately worry.
 
This was the reason, that SOTDMA (B+) was intoduced). The Satellite's pick Up the AIS traffic.


Our American Kissin Cousins drove this forwards years ago when they required 48 hours notice of arrival at all USA ports and still vessels were turning up unannounced. Now they can see who is coming to dinner.

Beware happy cruisers. Oz has a similar requirement however in the event you do not have VHF they will accept a departure message from Capetown and allow for the fact you might arrive early or late.
 
Yup aware of this options, just wondering if my existing equipment might be picked up as well.

I'm actually asking on behalf of a relative who would like to keep tabs on us from ashore.
Do they also keep tabs on you when nip off to the boozer or chippie? Thought not. Advise them to take their panic panties off and to don a real pair.
 
For Class B, satellite AIS is not that reliable, meaning there are long periods during which the signal is not picked up, long periods sometimes means "days".
We noticed that while following Imocas, some of them had classB transponders (not sure if CSTDMA or SOTDMA, lower or higher power), they were tracked on Marinetraffic, actually MT just showed "pleasure vessel" -without subscription they will not let you know where is the specific boat you are looking for- but if you know one boat or a group of boat is in a specific position then you may infer the one on MT is the one you are looking for.
The OCC asked a price to follow a fleet and the per-boat fee would still be very very high.
I would not use satellite AIS: imagine someone on land seeing the signal disappear for one-two or more days... You may explain beforehand that technical problems might prevent the signal from being regular, but once it happens people on land immediately worry.
I think you can track a single named vessel for 99p/day if I'm understanding correctly. The rate drops swiftly for longer plans.
It might still cost a lot to track a fleet or to track all vessels.
 
I don’t think anyone meant for the use of marine traffic for our normal nav purposes but it’s useful to follow mates and other club members in their travels. The sat reports also does seem to report normal class B, we were picked up a couple of weeks ago in an area with no base station reception.
 
I don’t think anyone meant for the use of marine traffic for our normal nav purposes but it’s useful to follow mates and other club members in their travels. The sat reports also does seem to report normal class B, we were picked up a couple of weeks ago in an area with no base station reception.


You might have been picked up however that data is only available to those that visit tracking programs or pay to have it delivered to their business. Shipping still requires to watch what its own equipment tells it regarding traffic in its area.
 
Fully understand that, I only knew it was our boat as I did it looked as I was still on the river. Not going to pay 99p to look at detail though, would soon add up. Already pay for additional stuff of marine traffic, they soon start sucking you in. It seems though more signals that used to be accessible seem to be satellite now though, see quite a few recently that were in the middle of others that were full visible as normal
 
Apparently you can pay a subscription and receive AIS from vessels offshore, which is picked up by satellites.
I know this works for big commercial ships (class A?)
Will it work for our little Class B/B+ units?
Yes, the nominal subscription will give access to recreational/class B transmissions received from satellites when away from land base station reception.

My wife tracked our progress from
Canaries to Caribbean during a trip in Jan 20.
 
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Skylark you didn't mention which mode you used.
I'm surprised how little knowledge is around the satellite AIS transmission. As far I understand only SOTDMA is received by satellites. Would be nice know if it is the case.
Knowing that AIS is always monitored gives me more security.
There was a case in the Baltic that a ferry changed course because an other vessel came up on the AIS monitor, but there was also a yacht in the vincinity which had no AIS. The ferry run over the yacht and the yacht skipper died.
After this accident I installed an AIS Transponder.
 
Skylark you didn't mention which mode you used.
I'm surprised how little knowledge is around the satellite AIS transmission. As far I understand only SOTDMA is received by satellites. Would be nice know if it is the case.
Knowing that AIS is always monitored gives me more security.
There was a case in the Baltic that a ferry changed course because an other vessel came up on the AIS monitor, but there was also a yacht in the vincinity which had no AIS. The ferry run over the yacht and the yacht skipper died.
After this accident I installed an AIS Transponder.

They are two very different things: AIS for periodically monitoring a position from land, AIS for collision avoidance.
An AIS satellite broadcast position vector can have a lot of delay, it can be ok for someone on land, but hopefully no one else in a collision course with you will use it for his collision avoidance decisions.
 
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