AIS -too much clutter already?

[cookjwm]

I installed an AIS reciever this year and have been very surprised at the sheer volume of transmissions even sailing in the Blackwater. My alarm has been going off so often I have switched it off!Cannot quite understand why I need an AIS transmission from a sailing boat I can see with my eyes half a mile or a mile away.Or more. Hate to think what the Solent is like. Will just have to remember to switch the alarm back on for a passage! Would it be helpful if those of us with transmitters just used them when it was needed - poor vis, night etc. After all ,most of us do not use radar all the time....
Now if the various mostly power boats which nearly run us down and then swerve away had them fitted an alarm reminder on their boats might make life easier all round.....or am I ranting?!

 

[sailorman]

Rant fully accepted & agreed with

 

[Bru]

You're looking at the problem the wrong way round

It isn't the number of AIS transmitters that's a problem, it's the extremely poor software on the receivers on the leisure market

The lack of ability to differentiate between target types, set alarms based on CPA rather than range (some can, most can't), set stdifferent alarm criteria for Class A and Class B targets and (on my Raymarine kit at least) the inability to ignore targets that are moored or at anchor and the total lack of a facility to cancel an alarm AND ignore that target henceforth all add up to a pile of poo

And it's all software, it's not rocket science and it's a poor show that we have to put up with such shoddy implementation of what should be a good system

 

[Otter]

Got to ask why you had AIS switched on for sailing in the Blackwater! The problem of screen clutter has been around for a few years and is growing exponentially, it means the CPA alarm function is usually switched off. Trying to persuade people to switch off transmission is a dead duck, so keep your receiver for offshore passages and poor visibility, which is all it's really intended for anyway.

 

[sailorman]

Got to ask why you had AIS switched on for sailing in the Blackwater! The problem of screen clutter has been around for a few years and is growing exponentially, it means the CPA alarm function is usually switched off. Trying to persuade people to switch off transmission is a dead duck, so keep your receiver for offshore passages and poor visibility, which is all it's really intended for anyway.

quite so

 

[Koeketiene]

Inshore and in daylight, AIS is of very little use IMO.
However, offshore is when it comes into its own.

I usually take some persuading before I fit an electronic gizmo, but I do not regret fitting our AIS transceiver one bit.
On Channel X-ings it is on all the time. And when crossing busy areas such as a TSS it is reassuring to see the big boys adjust course/speed up/slow down to stay clear of you. Especially when crossing at night. In my personal experience, the statements often banded around on here that merchantmen filter out Class B AIS transmissions are manifestly untrue. They might do so in the Solent (I certainly would), but there as a whole world outside the Solent - or Blackwater for that matter.

Another reason I have AIS on is that when sailing single or shorthanded it reassures the ever-worrying home front.

Last, but not least: safety. When I needed to contact Thames Coastguard on Saturday night (engine failure, gale force winds forecast 'soon', veering wind, navigating the Harwich approaches) the CG immediately had our position/course/speed and tracked us all the way. Thames CG also informed Harwich VTS of our predicament and they too tracked us on AIS.
Assistance - when it was eventually required - was on the scene promptly.

Whilst I do agree that AIS clutter inshore is an annoyance, it is IMHO a minor one and one I am willing to put up with when compared to all the benefits AIS offers.

 

[Champagne Murphy]

We have a receiver only. What's the cost of a decent transponder now? Are they coming down in price?

 

[Otter]

£300 - see the threads on Matsutec, also gives you a decent stand alone GPS 'plotter' but no map function. Has some nifty XTE functions as well.

 

[Koeketiene]

We have a receiver only. What's the cost of a decent transponder now? Are they coming down in price?

This is what we've got: http://www.cactusnav.com/digital-yacht-ait2000-class-transponder-p-12125.html

When I researched AIS transmitters, this one suited our needs best:
- Works great with my Rasperry Pi running OpenCPN
- Has a stand-alone GPS antenna. So should my Furuno GP32 die at some point, this is more than capable of doing the job.
- Works well with our Digital Yacht 3-way antenna splitter (FM/VHF/AIS).

Your requirements/needs may be entirely different from ours, and I'm sure there are perfectly adequate models to be found in the £300-500 range.
This makes a Class B AIS transponder cheaper than say a SeaMe active radar reflector whilst being, in my view, much more useful.

 

[Vara]

My great regret is that when I upgraded my plotter I only paired it with an Ais receiver. Now saving my pocket money for transceiver.

I think the perceived clutter problem is a peculiarly Solentcentric problem, sailing out of Dover I need all the help I can get.

 

[Boz]

Inshore and in daylight, AIS is of very little use IMO.
However, offshore is when it comes into its own.

Whilst I do agree that AIS clutter inshore is an annoyance, it is IMHO a minor one and one I am willing to put up with when compared to all the benefits AIS offers.

My 'two penneth' has to be with OR4751, too much clutter never bothers me and it's often useful to know the length, beam and draft of a nearby boat not to mention the MMSI and callsign.

 

[johnalison]

I keep my alarm permanently off, preferring to check the screen often enough. I also keep my transmitter switched on. If people want to grumble at me, it's their problem. I cope with clutter by either turning AIS off or zooming in for clarity, which doesn't seem like much hard work. I might go into stealth mode going through the Solent, but otherwise I can't be bothered, and it saves me having to text friends and family to tell them where I am.

 

[DipperToo]

Inshore and in daylight, AIS is of very little use IMO.
However, offshore is when it comes into its own.

I usually take some persuading before I fit an electronic gizmo, but I do not regret fitting our AIS transceiver one bit.
On Channel X-ings it is on all the time. And when crossing busy areas such as a TSS it is reassuring to see the big boys adjust course/speed up/slow down to stay clear of you. Especially when crossing at night. In my personal experience, the statements often banded around on here that merchantmen filter out Class B AIS transmissions are manifestly untrue. They might do so in the Solent (I certainly would), but there as a whole world outside the Solent - or Blackwater for that matter.

Another reason I have AIS on is that when sailing single or shorthanded it reassures the ever-worrying home front.

Last, but not least: safety. When I needed to contact Thames Coastguard on Saturday night (engine failure, gale force winds forecast 'soon', veering wind, navigating the Harwich approaches) the CG immediately had our position/course/speed and tracked us all the way. Thames CG also informed Harwich VTS of our predicament and they too tracked us on AIS.
Assistance - when it was eventually required - was on the scene promptly.

Whilst I do agree that AIS clutter inshore is an annoyance, it is IMHO a minor one and one I am willing to put up with when compared to all the benefits AIS offers.

Sums up the situation perfectly.

I would add that it is worth mentioning to 'the home front' that it is not unusual for your vessel to disappear from tracking websites such as vesselfinder or marinetraffic. The class B transmitters are low power compared to the commercial systems and about the middle 1/3 of crossing the Thames estuary the the shore based receiving stations 'lost' my signal.

As regards another question posted, I purchased a McMurdo Smartfind M10 Transmitter (which is a re-badged Comar 108). The unit has a multiplexer integrated, two NMEA ports and an SD card for data logging as well as the GPS antenna with 10m cable. JGTech were doing deals at £399 but not sure if that is still available.

Most, if not all, AIS transponders have the capability to operate in 'stealth' mode - it is up to the owner to make sure that an appropriate switch is fitted.
One pre-requisite in fitting a transponder is that many will not operate until they have been programmed with your radio MMSI number. A benefit of this is that any commercial traffic can easily raise you on the radio in case of any pending emergency and they know your vessel details.

 

[Koeketiene]

I would add that it is worth mentioning to 'the home front' that it is not unusual for your vessel to disappear from tracking websites such as vesselfinder or marinetraffic. The class B transmitters are low power compared to the commercial systems and about the middle 1/3 of crossing the Thames estuary the the shore based receiving stations 'lost' my signal.

Yet, the home front tracked us all the way across the North Sea on Marinetraffic

 

[sailorman]

we came in via S Cork (Medusa Ch ) to get a better wind angle into the hbr

 

[DipperToo]

Yet, the home front tracked us all the way across the North Sea on Marinetraffic

On the last occassion it was vesselfinder that 'lost' the signal 15 miles out. Maybe Marine Traffic has better relay and shore stations? Also, it depends on which shore based base stations are used and their height above sea level. Marine Traffic does also use Satellites to monitor AIS data? My AIS aerial is only on the pushpit whereas if it was higher then a greater range. Interestingly I receive AIS data on my plotter from up to 18 miles away so quite sufficient for normal use.
I will try to see if Marine Traffic does a better job when I am next crossing the Thames estuary.
Although the Vesselfinder produced the correct 'track', it was noticed 'at home' at one time that the 'last position reported' was 1.5 hours behind when I was in the middle of the estuary (outside route) from Ramsgate to Harwich. It seemed to interpolate when shore based stations started receiving data again (20 miles out from Harwich).

 

[johnalison]

There is in fact one very useful inshore function of AIS. This is to determine if there is a ship coming out of a harbour unseen around a corner hidden by buildings or a bend in a river. In fact, I have just been using this in the Kiel canal which is quite bendy in places.

 

[AliM]

We were lost from Marinetraffic.com just outside Borkum (a pretty major North Sea German port) and only reappeared off Norderney, then lost again most of the way into the Elbe, and found again off Cuxhaven. Our shore contact was a bit concerned when we disappeared first time, and then quite amused as we apparently sailed over several islands. So, if you use AIS for your relatives to keep track of where you are, please warn them that AIS is reliable but the monitoring stations have gaps!

We also turn off the alarm, but monitor the chartplotter to work out which signals to worry about (eg large ships 2 or 3 miles away or less), and which to more of less ignore (yachts which may pass a few feet away).

As far as clutter is concerned, our record on this trip has been 100 AIS signals within 1.3 miles of us - that was passing through Amsterdam on the North Sea canal.

We also found the AIS interesting on the Kiel canal. There are lights on the side of the canal warning various categories of large ships to stop, and you can work out what is coming in the other direction that determines that oncoming ships must stop. Then we passed one ship that was bound for the timber yard just a mile from our mooring... Endless interest on an otherwise rather boring canal.

You can see that Johnalison and I are weather bound, from our postings, can't you - he is near Kiel, and I am in Denmark, and the wind and rain are all getting a bit much!

 

[RAI]

You could try vesselfinder.com as an alternative to marinetraffic. Or for professionals, vesseltracker.com, which also offers satellite AIS tracking for the wealthy.

 

[cookjwm]

Interesting views....take Erbas's point, the software ain't too clever, also agree that its not needed in the Blackwater very often and indeed that's not what i bought it for. However, it switches on with the plotter and the software upgrade also now defaults to switching on the radar -which I def. do not need in the blackwater!So I switch the alarm off rather than mess about even more putting a switch in. As others have said, it is useful to monitor, I just do not want it shouting at me all the time!

But it remains -if I do not need to recieve in Blackwater, why do so many transmit?

Still, glad I have it