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PEEK A BOO Grandeur where are you?

palofmine

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DEIx15x8

DEIx15x8

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Ships don't always have their AIS transmitting. I'm not sure why that is. I know that Independence is often difficult to track.

 

All ships must have their AIS transmitters on at all times while sailing (may be able to shut it off while docked but never seen any do that unless dry docked). This is the only way vessels can see who is around and where they are headed in order to avoid collisions. Turning it off would be like turning a plane's radar off. The reason that they often disappear is that just like the radar system used for tracking planes, they can only be seen when in range of a receiver (either on land or on another ship). http://marinetraffic.com/ais/ is a crowd sourced network of individuals (as well as some corporations and ports) who own AIS receivers that track the ships near them and report their locations back to the central database on the website that the public can view. When a ship gets away from land it leaves the range at which those on shore can pick up the AIS signal and report it back so it appears to vanish until it gets near land again and someone else picks it up.

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palofmine

palofmine

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Yeah its been a n hour or so, cant pick her up on the map.

 

 

All ships must have their AIS transmitters on at all times while sailing (may be able to shut it off while docked but never seen any do that unless dry docked). This is the only way vessels can see who is around and where they are headed in order to avoid collisions. Turning it off would be like turning a plane's radar off. The reason that they often disappear is that just like the radar system used for tracking planes, they can only be seen when in range of a receiver (either on land or on another ship). http://marinetraffic.com/ais/ is a crowd sourced network of individuals (as well as some corporations and ports) who own AIS receivers that track the ships near them and report their locations back to the central database on the website that the public can view. When a ship gets away from land it leaves the range at which those on shore can pick up the AIS signal and report it back so it appears to vanish until it gets near land again and someone else picks it up.
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DEIx15x8

DEIx15x8

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so maybe im obsessed, still dont see her.

 

You won't find her until maybe 11am tomorrow when she nears Bermuda. She's out to sea until 3pm tomorrow. It's a long arrival for Bermuda though that snakes along the coast of the island where she can be picked up.

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emmy

emmy

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You should be able to view Grandeur later when she is docked in Bermuda:)

 

http://www.portbermudawebcam.com/

 

I will also be watching that great webcam in Bermuda as Grandeur makes her first appearance there since the fire.

 

It will be a chance for many of us to get our first good view of her LIVE. :)

Bermuda is waiting to welcome her!

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chengkp75

chengkp75

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All ships must have their AIS transmitters on at all times while sailing (may be able to shut it off while docked but never seen any do that unless dry docked). This is the only way vessels can see who is around and where they are headed in order to avoid collisions. Turning it off would be like turning a plane's radar off. The reason that they often disappear is that just like the radar system used for tracking planes, they can only be seen when in range of a receiver (either on land or on another ship). http://marinetraffic.com/ais/ is a crowd sourced network of individuals (as well as some corporations and ports) who own AIS receivers that track the ships near them and report their locations back to the central database on the website that the public can view. When a ship gets away from land it leaves the range at which those on shore can pick up the AIS signal and report it back so it appears to vanish until it gets near land again and someone else picks it up.

 

Actually, you are not quite correct. Ships have been avoiding each other using radar long before the AIS system was mandated. When ships were approaching each other, they would call on VHF radio and request the approaching ships name, and then chat about how close they would plan on passing. AIS transmits the ship's information to each other, for display on the radar screen, so the initial radio call can be directed to a ship by name. AIS is a security measure, not a navigation measure. It allows governments to know where a ship is, and is analogous to the identification signal that airplanes send so that airport radars can make a little tag and identify each little blip on the radar screen.

 

The reason that public vessel tracking sites like Marine Traffic cannot always find a ship is that there are restrictions written into how those sites acquire the signals, for anti-terror situations. When Grandeur was underway from Freeport to Baltimore, on another thread folks were asking where she was, as Marine Traffic did not show her signal, but a commercial vessel tracker that I subscribe to had her position. The only time a ship is allowed to turn off their AIS is if there is a known security situation that would be worsened by transmitting the ship's position. The ship will still show up on radar, but the name would not.

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