Marine Traffic - AIS

[Totomubungo]

Hi folks,

Anyone up to speed on AIS or SME on Marine Traffic issues?

Wondering why certain vessels switch off their transponders while still under power and at sea - I thought this was illegal?  Any ideas?

Lep

[Higgins]

It's probably not turned off but there is no receiver to get the ais signal.

[Kieran]

AIS is a short range tracking system, that works off VHF radio. Ships have to be withing range of a reciever for it to show on the websites. GPS is the only way to track a vessel constantly, and only Coast Guard, Military, and ship owners have access to that...

[wackerwhelan]

Some ships turn off AIS because AIS is information that the ships gives which might not be 100% accurate, such as ships position. You can switch it off and just use the normal radar to get 100% accurate information.

[Totomubungo]

OK, thanks for that.  Interested as the "Julia" when just off shore isn't visible on MT - thought it might be a Company thing?

Certainly during the sea trials earlier this week, it was on and giving the speeds described later on this site and detailed in the Company newsletter.  I know the range spec is some 40nms (Irish Ferries traffic is visible throughout the entire range of the journey(s)).  Could be that Julia's route is further south and out of range??

Lep 

[Collision-course]

According to AIS Julia and Pont Aven are passing each other off Cobh , I wonder if there is anyone down there with a camera.

[adrian]

OK, thanks for that.  Interested as the "Julia" when just off shore isn't visible on MT - thought it might be a Company thing?

Certainly during the sea trials earlier this week, it was on and giving the speeds described later on this site and detailed in the Company newsletter.  I know the range spec is some 40nms (Irish Ferries traffic is visible throughout the entire range of the journey(s)).  Could be that Julia's route is further south and out of range??

Lep 

HI
As far as I know, Julia keeps her AIS 'on' all the time - but, as others have said, it's essentially a short-range VHF system, with only a few 'voluntary' land-based rx stations. If you look on Marinetraffic.com you can click the 'Show Stations' checkbox and you'll see where they are located. The one that covers Swansea Docks is located inland, by the motorway, and can't always 'see' Julia when the tide's out <g>

One of our supporters, who has a much better location near Swansea, is planning on putting up an AIS RX station, which will provide better coverage -
but I expect that she'll always drop 'off the radar' in the middle of her trip...

When she came down from the Baltic we had a 'follow the ship' link on the campaign website, and tracked her successfully all the way to the Bristol Channel - wherupon she disappeared! I had one or two worried emails that day <g>

Great to see her settling into the schedule - speaking to one of the co-op people yesterday they've aleready got more than 20% of their target bookings for 2010 - which isn't bad going.

Adrian
www.peoplesferry.com

[derekchoochoo]

Been watching her on AIS this morning - seemed to be steaming very slow along the Gower (11 knot) - and the Dalegarth appeared to come out to rendevous just inside Mumbles Head at about 0740 - came alongside berth about 0820. Hope all is well - after some cracking trips the last few nights - looks like she did Friday night's in a little over 9.5 hours, with a couple of 20 knot speeds appearing!