AIS again

Benbow

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Accepting all that has been said about the limitations of AIS and the, at best misleading, term “AIS radar”…

….would it not be cool, and possibly even useful if other things, like gas rigs, LANBY’s, wind farms, etc transmitted AIS data?

Or is it already planned ?
 
Erm - desitnation, direction and rate of travel, MMSI number ......
is it really nessersary though? especially if the AIS data is shown on an electronic chart - cos they should be staring you in the face ....
 
Just listen out for morse "U" in fog !

I've heard The F***ing thing for days on end while waiting for a helicopter to get home for a beer or three ! !
 
It could be very useful. In my view the true power of AIS lies in a combined RADAR and AIS system - exactly the same as the air traffic control system whereby the RADAR gives the targets and the transponder overlays the extra information. However ( and this is the important bit) the transponders are NEVER used alone, it is either just RADAR or RADAR + Transponder.
So I think AIS alone is worse than useless. The sensible choice is just RADAR or RADAR with AIS overlay - shouldn't be long till raymarine add some software functionality to their sets to allow this. Obviously the nice addition to this type of system with combined RADAR and AIS would be to have the AIS info (maybe just the name and some sort of physical description) for major buouys, oil rigs etc.
 
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So I think AIS alone is worse than useless.

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This widely stated claim on Scuttlebutt surprises me.

In the most closely investigated collision between a commercial vessel and yacht in recent years, it is clear that the presence, misuse and distraction caused by a radar installation on the yacht actually contributed to the collision.

By contrast I believe that had the yacht (the one with the Kiwi sounding name) been equipped with a handheld AIS/plotter that was extremely simple to use and was able to predict a collision with pin-point accuracy, then the collision would not have occurred.
 
I understood from the report that it was NOT the fact that radar was being used , but it was attributed, at least in part, to the skipper's INTERPRETATION of the information that was displayed.

As for AIS, my personal opinion is that it is just another AID to navigation, and the information needs to be combined with all the other pieces of information that the skipper has to hand.

No doubt that some boffin will combine AIS with radar as in air trafic control, but as far as I'm concerned, this will just provide 2 bits of information combined, and it is STILL up to the skipper to interpret these, and be aware of the limitations.

The colregs say something about not relying on radar information alone. I would add "Don't rely on radar, AIS or both together, alone"


All IMVHO
 
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Warsash College does. You can see it on AISlive.

It's the only target you can trust not to run you down.

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if only that were true of its students
 
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So I think AIS alone is worse than useless.

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Well I did not mean to reopen this. But I don't see how any additional information can be other than useful, provided it is understood.

Certainly I imagine for a small yacht in mid ocean where the biggest collision hazard is big fast ships and electrical power is at a premium, it is a lot better than useless.

I don't think anyone is advocating relying on AIS alone for collision avoidance.
 
Re: AIS again. It\'s to soon.

I too don't want to start this again but.....

I can think of no circumstances were the un-reliable info, presently generated by AIS, can be anything but a distraction to a yachtsman in congested waters.

Ask yourself would you like your GPS to give you duff info or would you prefer it to switch off all together. I know I'd prefer no info to inaccurate info.

The future is good for an AIS type system. But it's to early to put much faith in what's on offer now.
 
Re: AIS again. It\'s to soon.

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the un-reliable info, presently generated by AIS

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Incomplete maybe.

I guess no more than 20% of yachts crossing the channel each have radar onboard. So for the other 80% is it not preferable to have precise knowledge about the movements of most of the big stuff in poor visibility?

I remember getting caught out in bad vis between Le Harve and Brighton. I could hear the big stuff thumping past to be followed 5 minutes later by a wash. I would most definitely want an AIS receiver in the same circumstances.
 
Re: AIS again. It\'s to soon.

Quote from Benbow's post-
But I don't see how any additional information can be other than useful, provided it is understood

Quote from jonjo
So for the other 80% is it not preferable to have precise knowledge about the movements of most of the big stuff in poor visibility?


I think that the important bits, for me anyway, are "...provided it is understood" and "...the movements of most of the big stuff ..." (my bold)

That's the nub of my earlier post. I wouldn't knock AIS or radar, but I wouldn't want to base my decisions on information from these sources alone.
 
If I am in the vicinity of a major port, I listen-out to port control. I think it would be negligent not to. Your logic says I should turn off my VHF because a) it is distracting and b) some vessles are not talking to port control. I think not.

I don't understand why this is such a contentious issue, AIS is just another source of information. Like all information sources it has its limitations, if you know this you can only benefit.
 
James

Now pay attention at the back there! /forums/images/graemlins/laugh.gif You need radar (the real one) to set off the Racon in which case the AIS device is an additional and not the primary tool and few can criticise that.

BTW isn't it time for some in-depth hard hitting journalism on this?

Robin
 
1. Rigs, Lanby's and Wind Farms are static apart from the former, which you can learn about in notices to mariners when stopped and should have AIS transponders active when moving. The latter are charted and if new will be announced in notices to mariners. So why do they need AIS?

2. AIS is already available if you have an FM capable reciever with accurate tuning and direct discriminator output, such as an ICOM PCR1000. Just add software called ShipPlotter and scan suitable charts for your area of operation and you have a comprehensive AIS plotter.
 
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