# A question...



## 40907 (Sep 26, 2009)

There is a ship passing Quoin Point (west of Agulhas) by the name of Spring Breeze 1. Its shown as a navigational aid (Navaid Type: Beacon, Cardinal S). Why would that be so? There is a picture of the ship on the marinetraffic.com system and it doesn't look at all like I'd expect a navaid to look!

http://www.marinetraffic.com/ais/#


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## marco nista (Jan 29, 2008)

Finger trouble setting up the AIS ?

Duff info being broadcast is not unknown


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## Pat Kennedy (Apr 14, 2007)

There is a pilot launch on the Mersey which is shown on AIS as a 'pleasure craft'.
Another one often describes itself as travelling at 21 knots, 'under sail'
I think its just the lads having a laugh. 
Regards, 
Pat


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## 40907 (Sep 26, 2009)

Pat Kennedy said:


> There is a pilot launch on the Mersey which is shown on AIS as a 'pleasure craft'.
> Another one often describes itself as travelling at 21 knots, 'under sail'
> I think its just the lads having a laugh.
> Regards,
> Pat


Hi Pat. I would have thought that that is rather a dangerous thing to be having a laugh with.


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## kewl dude (Jun 1, 2008)

AIS publishes the information from the ships automatic transmitter. 

But the crews of commercial ships as well as yachts and service craft are known to be less than fully professional. 

I saw a cruise ship entering New York classed as a Mega Yacht and I too saw a sailing ship that said it was going way faster than possible.

Attached two images the first shows the QM2 in blue and the container ship OOCL-Kaohsiung in yellow. I noticed that they seemed to be on an imminent collision course so I followed them for an hour when I saw as shown in the second image the two ships information plaques merge.

I thought I had just witnessed a nasty ship collision. Yet to this day I have been unable to find out anything. The container ship continued on its course and sixteen knot speed lined up for New York harbor. Later as it got closer to the narrows it slowed to 12 then 8 knots.

Immediately after the 2344 (my local daylight time, this took place October 25) apparent collision the QM2 stopped and drifted for about an hour and a half before continuing on into Newport RI where it docked at 3 AM my time, 6 AM in Newport. I stayed with it until QM2 was docked.

NO other craft approached the QM2 during this drift time. And I knew she was drifting since her heading slowly swung around facing back where she had come from, but she was reporting zero forward motion.

So either some folks have done a good job of making this apparent at least near miss just go away, or it never happened?

After this I did a LOT of reading online about AIS and learned it was entirely possible, due to transmitting for free internet consumption, published signals are as much as three days old. 

These two ships COULD have passed that exact same place in the ocean DAYS apart, but FREE published as current positions.

I understand that the only way to ensure you are getting up to the minute AIS information is to subscribe to the services. Which are not that costly but more than I want to spend on an occasional hobby. I suspect that if I lived in view of a major waterway I would amend that decision.

I attach a third image showing ships broadcasting as being in the port of Los Angeles. 

About half way between Long Beach and San Diego is Oceanside. A LARGE small craft marina - perhaps 800 slips? Power and sail yachts and a small commercial fishing fleet + US Marine Corp Camp Pendleton commercial ship piers, that take moderate size container, Lash and RO/RO ships as well as US Navy combat ships that deploy with Marines and hospital ships.

Anyway just to the east of Oceanside is Vista, and Vista is where I have lived the past eighteen years, fifteen in my present home.

Greg Hayden


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## Rob Crossland (Dec 22, 2010)

Hi Guys,
I have found that the AIS info. is suspect. Often nothing is showing at the Dundee [Scotland] berths yet I see them as I drive past. Either the info. broadcast on AIS is out of date or the vessels turn their signals off when berthed. Your views would be welcomed. PS We have an AIS station "Monifieth Dundee - ID 299" just along the road.
Regards
Rob Crossland
(Novice)


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## 40907 (Sep 26, 2009)

Rob Crossland said:


> Hi Guys,
> I have found that the AIS info. is suspect. Often nothing is showing at the Dundee [Scotland] berths yet I see them as I drive past. Either the info. broadcast on AIS is out of date or the vessels turn their signals off when berthed. Your views would be welcomed. PS We have an AIS station "Monifieth Dundee - ID 299" just along the road.
> Regards
> Rob Crossland
> (Novice)


The port authorities don't always pay as much attention to the the computer that does the magic for us as we would like them to. The other stations like Monifieth are amateur and do go down occasionally. The ships don't turn their systems off.


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## smithax (Jul 16, 2009)

I think this is a good example of why AIS should never be used for anti collision. The AIS information depends what information is input by the crew of the vessel. The GPS info could be incorrect, wrong chart datum, it's failed and is in DR mode etc etc. 


S


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## 40907 (Sep 26, 2009)

My son trusts my ais info. He phoned a while ago and said "Hey, Dad! Where are we - I'm lost!" So I told him he was an idiot. "I warned you not to sail so close to the edge of the earth!" Bloody kids! Taught him everything I know and he STILL knows nothing! (Cloud) [=P]


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## Davie M (Apr 17, 2009)

It proves if you put rubbish into a computer system you will get rubbish back out.
Davie.


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