I want AIS

snowleopard

snowleopard

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Having just made a passage through the Dover straits on a boat with chart plotter and integrated AIS I'm hooked. I've been thinking about splashing out on radar for a while but now I've decided AIS does most of the job better & cheaper.

The drawback seems to be spotting small vessels and fixed obstructions but the only times I have rally felt the need of radar is among shipping in poor vis.

Any comments?

Now I need to settle on a suitable PC based chart plotter & a source of charts. Any recommendations on free / open source plotters?
 
Now I need to settle on a suitable PC based chart plotter & a source of charts. Any recommendations on free / open source plotters?[/QUOTE]

We fitted a Digital Yacht AIT1000 transponder linked to Open CPN software and CM93 charts, been delighted with the performance and has already enabled us to wake up one ship that was on a collision course. We will be sailing in the Channel Isles and France for a week or two but when you see the boat back in the Lake give me a ring and I can show you.

Cheers

Peter.
 
snowleopard said:
Having just made a passage through the Dover straits on a boat with chart plotter and integrated AIS I'm hooked. I've been thinking about splashing out on radar for a while but now I've decided AIS does most of the job better & cheaper.
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As an INFORMATION service AIS is obviously the ideal but radar is a NAVIGATION system and the two should not be confused. Of course there are systems where AIS data is overlaid on the radar screen with the radar plots.

Decide what you want, a passive information system (AIS) or an active navigation system (Radar), it's up to you.

They both have their merits.

Personally, here on the south coast, I have more use for the AIS information - that may not be the case if I were based on the west coast of Scotland - I have little use for radar for recreational purposes despite having used radar all my working life.

Tom
 
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Adonnante said:
Now I need to settle on a suitable PC based chart plotter & a source of charts. Any recommendations on free / open source plotters?
Click to expand...

We fitted a Digital Yacht AIT1000 transponder linked to Open CPN software and CM93 charts, been delighted with the performance and has already enabled us to wake up one ship that was on a collision course. We will be sailing in the Channel Isles and France for a week or two but when you see the boat back in the Lake give me a ring and I can show you.

Cheers

Peter.[/QUOTE]

Are you using the USB input into your PC. If you are can I ask what COM port you have the AIS on? I have been having problems with the Comar multi partly with the COM port choice

Thanks

TudorSailor
 
I also have OpenCPN with CM93 charts. AIS input comes from a combined VHF/AIS radio. With my combined VHF/AIS aerial at the top of the mast I can see ships going up and down the Mersey from Peely Weely.

snowleopard said:
Having just made a passage through the Dover straits on a boat with chart plotter and integrated AIS I'm hooked. I've been thinking about splashing out on radar for a while but now I've decided AIS does most of the job better & cheaper.

The drawback seems to be spotting small vessels and fixed obstructions but the only times I have rally felt the need of radar is among shipping in poor vis.

Any comments?

Now I need to settle on a suitable PC based chart plotter & a source of charts. Any recommendations on free / open source plotters?
Click to expand...
 
snowleopard said:
Having just made a passage through the Dover straits on a boat with chart plotter and integrated AIS I'm hooked. I've been thinking about splashing out on radar for a while but now I've decided AIS does most of the job better & cheaper.

The drawback seems to be spotting small vessels and fixed obstructions but the only times I have rally felt the need of radar is among shipping in poor vis.

Any comments?

Now I need to settle on a suitable PC based chart plotter & a source of charts. Any recommendations on free / open source plotters?
Click to expand...
I did an article in PBO June edition. Use your laptop, basically a Maplin £20 USB GPS dongle, Imray charts (£64 for the UK) come with chart plotting software PLUS AIS integration, then get a NASA engine and away you go.
Stu
 
skipper_stu said:
I did an article in PBO June edition. Use your laptop, basically a Maplin £20 USB GPS dongle, Imray charts (£64 for the UK) come with chart plotting software PLUS AIS integration, then get a NASA engine and away you go.
Stu
Click to expand...

That seems to cover most of it but surely you will need another antenna or a splitter and that puts the cost up quite a bit?
 
snowleopard said:
Having just made a passage through the Dover straits on a boat with chart plotter and integrated AIS I'm hooked. I've been thinking about splashing out on radar for a while but now I've decided AIS does most of the job better & cheaper.

The drawback seems to be spotting small vessels and fixed obstructions but the only times I have rally felt the need of radar is among shipping in poor vis.

Any comments?

Now I need to settle on a suitable PC based chart plotter & a source of charts. Any recommendations on free / open source plotters?
Click to expand...

Radar and AIS have technically nothing to do with each other, but AIS information can be superimposed on a radar screen. Have a look at Essential Boat Radar (Wiley Nautical) where you will find a full explanation.
 
Barnacle Bill said:
Radar and AIS have technically nothing to do with each other, but AIS information can be superimposed on a radar screen. Have a look at Essential Boat Radar (Wiley Nautical) where you will find a full explanation.
Click to expand...

I am fully aware of how the two function and the info they provide. The question is how to get the info onto a screen in a cost-efficient manner.
 
I think an AIS receiver would be a good thing for sailing in shipping lanes and well worth the money. I'd not bother getting an ais transmitter, most ships don't use the ais for spotting purposes they use lookout and radar, even when the ais can be overlaid on the radar it clutters it up and the two images aren't superimposed that often either due to various factors (mainly gyro error). In my experience the AIS is used to see who else is in port or around about (ie their names) I don't think anybody looks at it to find targets (the clue is in the name).
I agree radar on a yacht is largely superfluous and expensive on wallets and amps, whereas the ais is neither, and covers the majority of what yachties want the radar for - confidence that in fog or light winds they know if somebody is likely to run them down, it also provides a name to use on the vhf which the radar doesn't so you don't have to say 'ship in position...' or less helpfully 'ship on my port side'. Radar is great for lots of things but I'm not likely to fit one on my yacht, equally I'd not put to sea without one on my ship.
 
pugwash60 said:
I'd not bother getting an ais transmitter, most ships don't use the ais for spotting purposes they use lookout and radar
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I have also heard that ships can and do set their receivers to exclude AIS signals from pleasure craft so no guarantee they'll see you even if you've got one.

pugwash60 said:
...confidence that in fog or light winds they know if somebody is likely to run them down, it also provides a name to use on the vhf which the radar doesn't so you don't have to say 'ship in position...' or less helpfully 'ship on my port side'.
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In my experience, if you can't call a ship by name you won't get a reply. The name or better still the MMSI will generally get a response. An individual ship DSC call is unlikely to be ignored.

The other thing I found AIS good for was the CPA which you can't get on a radar unless you have a souped-up compass to feed the MARPA. Knowing the CPA can often remove the need for a radio call.
 
I'd strongly recommend the vhf 16 and using the ships name route, the old gmdss alarm goes off about a hundred times a day so the only ones a watchkeeper might look at would be a distress call, individual calls will mostly be ignored as they sound like just another coast station broadcasting a change to a buoy 500 miles away or forecast or whatever which you are also bombarded with via navtex and ntms - so routine all ships calls are filtered out by ignoring them and individual calls, on our ship anyway, sound the same when they come in.
 
EdBeynon said:
That seems to cover most of it but surely you will need another antenna or a splitter and that puts the cost up quite a bit?
Click to expand...

I have the Nasa unit plugged into a Ship modul Bluetooth multiplexer, along with feeds from a standalone nmea gps and the seatalk info. Also going into the NASA is a second VHF aerial on a pole which can be unplugged and stuck in the VHF radio if I ever have the misfortune to loose the mast. The benefit of Bluetooth is, I can take the netbook anywhere on the boat and still get the live feeds, useful for shrt handed sailing in the cockpit under a transparent bag!

I use Software onboard and CMAP charts, but have tried Shipplotter and the Imray charts mentioned elsewhere. Shipplotter is the best AIS software (30€ license), but you need to cobble together charts, it has no navigation capability, but does all the CPA TCPA etc. Imray (2009 edition) does NOT do these calculations, but is nice and easy to use.
The CMAP / SoB route means the charts are the same as on the chart plotter so crew get used to one look. However this is the most expensive.
 
Genoa said:
I use Software onboard and CMAP charts, but have tried Shipplotter and the Imray charts mentioned elsewhere. Shipplotter is the best AIS software (30€ license), but you need to cobble together charts, it has no navigation capability, but does all the CPA TCPA etc. Imray (2009 edition) does NOT do these calculations, but is nice and easy to use.
The CMAP / SoB route means the charts are the same as on the chart plotter so crew get used to one look. However this is the most expensive.
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Software on board is indeed costly. I wondered if the Shipplotter could use the Imray charts. The Imray has the whole of the western med for £30 which seems a bargain, but it would be nice to have the collision alarms of Shipplotter

TudorSailor
 
Used with Mk 1 Eyeball

In the Solent or Busy ports AIS is a PITA, bl**dy alarms going off every 2 minutes, however on a cross chanel it's good news, it "sees" ships before you do and even beeps if they are "targets".

It centers the mind on looking out, shows you the course and speed of the offending hitter and leaves you time to decide what to do before the b*ggers are on top of you.

It's no substitute for RADAR but a nice comfort factor when the alarm goes off and you wake up.

Ian
 
snowleopard said:
I have also heard that ships can and do set their receivers to exclude AIS signals from pleasure craft so no guarantee they'll see you even if you've got one.
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This is a myth -- though it does have a basis in reality.
AIS has been compulsory for most commercial vessels for at least six or seven years but it was being phased in for five years before that. So some earliest installations were in place before the specification for Class B was finalized.

These early AIS A transceivers were not able to receive the "static" part of the AIS B message. So a ship's watchkeeper would be aware of the presence of a Class B transceiver, and would be able to read its position, course, and speed, but would not know its name. Most of the equipment affected has been updated or replaced, so the problem is fading out.

Another possible source of this myth is that some PC software -- the kind intended for shore-based hobbyists to play with -- can "filter out" AIS B data.

But any ship's officer who tried to use this kind of software would be breaking Rule 5 of the colregs, and if a collision occurred which could have been prevented if he had been using AIS, he would almost certainly lose his license and he and his employers would find themselves in court facing charges of anything up to and including manslaughter.

"Filtering" is not like the sea clutter control on a radar: it could only be deliberate, rather than being the unwanted by-product of a perfectly legitimate adjustment.
 
I use a laptop with a Comar USB AIS with both AIS capability on the Imray Digital Chartplotter and also Shiplotter. The latter is shareware and costs about £20 to sign on after trial. Link is here:

http://www.coaa.co.uk/shipplotter.htm.

It is a little flaky to set up and run on my PC, but good functionality- eg gives range approach alarm & CPA, which the IDC AIS does not, but you will need to scan charts in unless you have old Maptech BSB charts, which it can handle. If it does recognise Imray charts, I have not been able to find out how!

Edit Apologies- just noted Genoa said most of this earlier in the thread, but at least I can confirm it!
 
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