AIS Etiquette

ferrispeterchris

ferrispeterchris

Well-Known Member
Joined
13 Aug 2005
Messages
850
Location
Bangor, County Down
Visit site
I was wondering if this exists.My reason for asking is that in my local marina there is a motor sailor which has been sending an AIS signal for at least the past two years and has not moved in that time.I know I'm getting old and grumpy but this reminds me of the prats in the motoring fraternity who have fog lights permanently turned on! Rant over,have a nice day. Peter.
 
Don't see its doing any harm? Is the owner actually using the AIS data (retrieved via one of the internet sites?) as a way of monitorring the boat? He knows its still there, must be reasonably afloat and that it still have power getting to the batteries?
 
Owner is probably using the signal as a security location device, if he sees it moving on his home or office PC, then its been nicked.
Could also probably wire the AIS on/off switch through an intruder alarm, again if it goes off some has gained entry to your boat. Or even through a high bilge water switch, saves a trip down to the boat.

I must have put my inventor cap on this morning.
 
RIB_imposter said:
Don't see its doing any harm?
Click to expand...
A Red Funnel ferry's AIS started to permanently transmit her position and speed (30kn) at the entrance to Southampton Water just off Calshott in Nov 2005. This went on for several weeks. Red Funnel are a professional outfit with, hopefully, professional standards of maintenace and I've always wondered whether Class A (or is it B?) fitted to leisure craft might be inadequately maintained and start spewing out erroneous position, course and speed data to the consternation of others?
 
ParaHandy said:
A Red Funnel ferry's AIS started to permanently transmit her position and speed (30kn) at the entrance to Southampton Water just off Calshott in Nov 2005. This went on for several weeks. Red Funnel are a professional outfit with, hopefully, professional standards of maintenace and I've always wondered whether Class A (or is it B?) fitted to leisure craft might be inadequately maintained and start spewing out erroneous position, course and speed data to the consternation of others?
Click to expand...

This video shows the output of the Gosport ferry yesterday. Spot the obvious mistake....
 
Pinnacle said:
I think you will find that he, ahem, posted it! :eek: :D:D
Click to expand...

Right - I was testing a new version of the software and thought for a minute that there was a problem with the heading attribute, until I realised it was jsut the ferry. So I recorded it, 'cos I'm like that.
 
Problem with this (assuming it is a class B transmission) is that there is only a limited amount of space in the AIS transmission system for class B. If a few hundred boats do this it will restrict to a point where it is impossible for a 'real' signal to get in.

Also the coastguard have a facility to switch off all of the class B transmissions if it looks as if the system will become overloaded, meaning that if it is you that is about to be run over by a ship the muppet with AIS switched on at his berth is preventing your vital information getting through.

Finally, many of the integrated AIS chart plotters at the commercial end have the ability to not display class B transmissions. Abuse of this type will encourage them to do that.

AIS IMO should only be in use if you are actually navigating or at anchor in an unusual place.
 
hightech said:
Quite simple, they have no compass connected, so they only get a COG line whilst ship symbol points north.
Click to expand...

Surely if the compass isn't connected, then it should send 511 in the 'True Heading' field to indicate that? Rather than just sending a bogus value.

Or have I read the specs wrong?
 
RIB_imposter said:
Don't see its doing any harm? Is the owner actually using the AIS data (retrieved via one of the internet sites?) as a way of monitorring the boat? He knows its still there, must be reasonably afloat and that it still have power getting to the batteries?
Click to expand...

Well, it's very annoying if your chart-plotter gives an alarm when near an AIS transmitting vessel. OK, you can acknowledge the alarm and kill it that way, but it is still annoying!
 
AntarcticPilot said:
Well, it's very annoying if your chart-plotter gives an alarm when near an AIS transmitting vessel. OK, you can acknowledge the alarm and kill it that way, but it is still annoying!
Click to expand...
It was more than annoying on my system - acknowledge the alarm and you shut it up only for the interval between signal updates - it made passage planning in a commercial harbour impossible until I finally got off my butt and fitted a separate switch to the AIS power feed.
 
ferrispeterchris said:
I was wondering if this exists.My reason for asking is that in my local marina there is a motor sailor which has been sending an AIS signal for at least the past two years and has not moved in that time.I know I'm getting old and grumpy but this reminds me of the prats in the motoring fraternity who have fog lights permanently turned on! Rant over,have a nice day. Peter.
Click to expand...

I agree with you sir. Just think what it would be like if all vessels had one and were on transmit all the time... It would create so much noise the system would be useless with alarms going off all the time. As it is I switch my reciever off in the Solent as it's constantly giving alarms I don't need. This is the best way to ensure all commercial shipping switches off channel B....
 
You must log in or register to reply here.

Share this page

Top