Tracking ship traffic via AIS

[Administrator]

Here's a link to a site which provides free real-time information to the public about ship movements and ports, mainly across the coastlines of Europe and North America. The project is hosted by the Department of Product and Systems Design Engineering, University of the Aegean, Greece. Data collection is based on the Automatic Identification System (AIS).

Bill

[ArtJ]

I imagine the pirates of the world would love this site!

[hanleyclifford]

I hope the pirates are stupid enough to use this website. What is missing, however, is the locations of submarines and other military vessels waiting to pounce on the bad guys.

[Administrator]

Pirates wouldn't need a website. All they have to do is get an AIS receiver and listen.

We frequently see Navy vessels on the Chesapeake. I don't recall them transmitting an AIS signal. Coast Guard vessels do, at least some of the time and depending on size. Cutters, yes. The RIB's, no.

Bill

[67c&ccorv]

For anyone on the Great Lakes I strongly suggest www.boatnerd.com - click on the "Vessel Passage" link and it takes you to a current AIS map showing the location of vessels on the Great Lakes equipped with AIS.

[Mo]

It's not unheard of to see the AIS turned off. Military and Civilian vessels can shut them down. The Queen Mary is off Halifax right now...just keep an eye. Last year she was doing an atlantic crossing and I'm sure she shut it down as she didn't stay on the screen after about 70 miles out....

[Mo]

Just checked on the Queen Mary...no AIS showing at this time. She is bound for Quebec City but there is one example...have a look and see where she re-actives her AIS.

[romantic comedy]

There is am app for that. I had a friend show me an iphone app that showed the ships in t he local area.

[Mo]

As of now the Queen Mary has it turned back on as she rounds Cape Breton and heads into the Gulf of St Lawrence. That is one ship that I have noticed not always sending out an AIS signal.

[Dave Neptune]

Traffic~14

FWIW on the U.S. Coast there is also Traffic on VHF 14. I use there service sometimes at night and in the fog as I have no radar. I call in and identify myself, give them my position course and speed and they then tag me into the traffic. They already have me and all others but no idea who you are. Once Identified they will keep me informed of any shipping traffic that I am nearing and visa versa. I have gotten course corrections for avoidance more than once~a great service if you haven't heard of it. They actually appreciate being able to contact any of there "blips" to get them to move to safety and save the paint on the bows of the big guys.

Dave Neptune

[67c&ccorv]

As of now the Queen Mary has it turned back on as she rounds Cape Breton and heads into the Gulf of St Lawrence. That is one ship that I have noticed not always sending out an AIS signal.

My guess is she is big enough to show up on just about any radar and likely an anti-terrorist measure just in case any Al Queda "sleepers" are out there waiting for an opportunity.

[Mo]

I'd say she discontinues transmitting but continues receiving...they have an option for that, I think. But, make no mistake, they will not leave themselves as a target with about 3000 passengers.

[Administrator]

The primary focus of AIS is to see and be seen by other vessels with AIS. They only show up on marinetraffic.com or something similar if somebody with an Internet gateway (usually on land) hears them and uploads what they hear.

I would be astonished if vessels like the Queen Mary EVER turn off their AIS transmissions. The cruise ships which dock in Baltimore never do in this general vicinity. Inside the COLREGS lines, vessels over 60 feet (I think) are required to transmit an AIS signal.

If you see the AIS position of a vessel suddenly disappear as it heads offshore, it's because it moved beyond the range of a land-based set of ears that could repeat what it heard. It's not because the vessel shut its AIS down.

Under certain conditions, AIS receivers can "see" much further than radar. Our ham radio club's local receiver, which feeds various websites, saw a vessel more than 200 miles away last week. Under "normal" conditions, VHF is line-of-sight. Google tropospheric ducting, or join a ham radio club!

Other than a GPS, I suppose, dollar for dollar, an AIS receiver is just about the most valuable navigational aid you can add to your boat, if you share the water with commercial vessels. An AIS transponder (transmit and recieve) is even better, though more dollars.

Someday, all vessels will have them. It wasn't that long ago that VHF radios were something special. My first one was crystal controlled, with maybe a half-dozen channels. Anybody else here that old?

Bill

[ndutton]

Ais

It wasn't that long ago that VHF radios were something special. My first one was crystal controlled, with maybe a half-dozen channels. Anybody else here that old?

Oh yeah. My first electronics package on a boat was a CB radio and an RDF, one was only slightly useful and the other utterly worthless. Ten-four.

Last year I monitored the tow of the U.S.S. Iowa from San Francisco down our coast to Los Angeles Harbor in the hopes of seeing her underway at our end for the sight of a lifetime. The lead tug had AIS and I could track course and speed changes via a website, plan an intercepting course and time.

It was a resounding success to say the least. After a four day tow we left my slip around 5 A.M. in darkness on a heading determined by AIS info and a little navigational arithmetic that we hoped would put us close. Just before dawn an hour or so later we picked up the unmistakeable dark silhouette of a WW2 battleship in the distance, about 8 miles off our coast and dead off our bow. We were one of only two boats crazy enough to try.

http://www.moyermarine.com/forums/showthread.php?t=6060

[Mo]

Bill is correct.

http://www.marinetraffic.com/ais/faq.aspx#4