AIS systems

caltexflanc said:

I am not sure what added functionality AIS transponder brings to the SAR situation that a DSC radio doesn't already supply. Can any of the AIS users enlighten me? Both are VHF based so are limited to that range.

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DSC only transmits your MMSI, position and a DSC alert message. AIS transmits continuously and sends much more information. Even when not in trouble, your position, bearing, speed, destination, status, callsign, vessel description and is being reported to all around you, as well as the Coast Guard and VTS.

SomeSailor said:

DSC only transmits your MMSI, position and a DSC alert message. AIS transmits continuously and sends much more information. Even when not in trouble, your position, bearing, speed, destination, status, callsign, vessel description and is being reported to all around you, as well as the Coast Guard and VTS.

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as long as you are in VHF range........but that's true with DSC too....

Thanks SS, appreciated.

So, bearing and speed. The MMSI data base the CG has contains the other info relevant for SAR purposes. More/other important detail would be provided with the Mayday you are transmitting right after you activated DSC: people on board and their condition, exact nature of distress, etc. AIS certainly would be an enhancement if your transponder had emergency functionality, though I think its biggest value is in bad visibility situations as an enhancement to radar (yours and others'), rather than SAR.

AIS wouldn't be particularly useful where I am at as the large vessels that frequent the area aren't required to have it; tugs, towboats, and fishing vessels. I've been watching siitech and marine traffic for years now (siitech always has more targets). It seems that many of the vessels that do have AIS, still don't have the data fields completed or are incorrect.

Funny enough, the recreational boats I see are usually set up correctly, and even leave it on in the harbour...

The AIS information provided by MMSI is quite helpful to us when on the water during poor/no visibility conditions. Knowing the vessel size, type and potential speed well in advance is another safety tool. Not to be known, is the CG has an AIS data base which they follow from many miles away - big brother or helping hand , take your choice.

I've been watching the BC and Washington ferries on AIS from my slip today, all are on time! Even more fun is watching the big ships departing Vancouver or Seattle and entering Straits of Juan de Fuca and those coming the other way. There is an amazing amount of traffic in the PNW cargo lanes.

This has been an interesting thread in that those who don't have AIS don't see the use and those who do have AIS, like it. Kinda like singles vs twins.

sunchaser said:

I've been watching the BC and Washington ferries on AIS from my slip today, all are on time! Even more fun is watching the big ships departing Vancouver or Seattle and entering Straits of Juan de Fuca and those coming the other way. There is an amazing amount of traffic in the PNW cargo lanes.

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That is a very good use for AIS. When I can't see out the window to check on the local ferries, I use AIS on my phone. Likewise when I visit my friends in Cordova Bay, I love identifying the ships going by on Haro Strait. I am a ship geek.

sunchaser said:

The AIS information provided by MMSI is quite helpful to us when on the water during poor/no visibility conditions. Knowing the vessel size, type and potential speed well in advance is another safety tool. Not to be known, is the CG has an AIS data base which they follow from many miles away - big brother or helping hand , take your choice.

I've been watching the BC and Washington ferries on AIS from my slip today, all are on time! Even more fun is watching the big ships departing Vancouver or Seattle and entering Straits of Juan de Fuca and those coming the other way. There is an amazing amount of traffic in the PNW cargo lanes.

This has been an interesting thread in that those who don't have AIS don't see the use and those who do have AIS, like it. Kinda like singles vs twins.

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did someone mention singles vs. twins??.........I agree and i have learned from this thread. I have concluded like you that it is a useful tool and dosen't appear to be expensive either.

Northern Spy said:

That is a very good use for AIS. When I can't see out the window to check on the local ferries, I use AIS on my phone. Likewise when I visit my friends in Cordova Bay, I love identifying the ships going by on Haro Strait. I am a ship geek.

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I agree with this. I think the ID aspect, for the pure enjoyment of it, will be a nice thing to have.

For those that use Marinetraffic.com , please be aware of certain limitations...to the free version at least.
Many times we will be NOWHERE near where it shows us. Case in point, our chief engineers' wife called the tug and wanted to know why we were only off the New Jersey coast (we had left 4 days prior, heading to the Bahamas). We were actually off of The coast of Florida.
This happens frequently.
A captain I know will unplug his AIS at the dock and move the tug to go grub shopping, get water etc. His supervisor will "see" him on Marine traffic as at the jobsite dock! when he gets back to the job, he re-connects his AIS antenna. Marine traffic is showing the vsl as at the original position.
Keep in mind that these boats use IMO compliant versions of Furuno AIS so it probably not an equipment malfunction. Also, while in New York, we are on the VTS system. So we would know quickly if the AIS wasn't painting the boats signature.

sunchaser said:

........ This has been an interesting thread in that those who don't have AIS don't see the use and those who do have AIS, like it. Kinda like singles vs twins.

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Or, Those who don't see a good use for AIS in their particular situation don't have it, and those who have determined that it would be a help in their particular situation have it.

Add to the "have it" group, the ones who find it an interesting toy.

sunchaser said:

The AIS information provided by MMSI is quite helpful to us when on the water during poor/no visibility conditions. Knowing the vessel size, type and potential speed well in advance is another safety tool. Not to be known, is the CG has an AIS data base which they follow from many miles away - big brother or helping hand , take your choice.

I've been watching the BC and Washington ferries on AIS from my slip today, all are on time! Even more fun is watching the big ships departing Vancouver or Seattle and entering Straits of Juan de Fuca and those coming the other way. There is an amazing amount of traffic in the PNW cargo lanes.

This has been an interesting thread in that those who don't have AIS don't see the use and those who do have AIS, like it. Kinda like singles vs twins.

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I'm not sure that's accurate...at least in my case. I certainly see the use of it...especially if I'm a harbor pilot PURPOSELY staying in a crowded shipping lanre with traffic that takes miles to turn or stop..and in all kinds of weather and darkness.

For a 40 foot boat that travels in daylight and good weather 90+ percent of the time, PURPOSELY avoids shipping channels, can manuever around a crab pot spotted only a few feet away.....I just see it as about the LAST piece of electronics I would get based on what it adds to my navigational capabilities.

Rather than comparing it to single vs twins...I'd compare it to having an EGT gauge when I already have a raw water flow sensor and I'm running an old, slow , non-turbo diesel. It's nice info...but I would rarely need any of it. If I'm a gauge guy (like some boaters I know), they would be drooling all over it and staring at it all day....

When it come free in a radio...I'm sure I will use the info occasionally and enjoy seeing who's out there...but for people to claim how much safety it adds is an injustice to newer/inexperienced boaters who might be scared into thinking it may be more important in a nav suite than RADAR, AP, etc, etc...

I think AIS does fall into the "Single versus Twins" syndrome somewhat. I didn't have the room to install AIS (and many other toys) on my last boat, but with more room comes more toys.

Having AIS is nice. It wouldn't be on my "Must Have" list, but it certainly is used, and is useful.

btw: I leave mine on in port as well (with email notifications if my boat leaves port). Just reassuring seeing it there and what traffic is moving in the area when ship watching.

I think Ron has made the most sensible posts regarding having or not having AIS capability.

I can certainly see its value for boating in certain waters or conditions. If we boated under those conditions we would install and use it. But in all the posts in this and other threads on other forums where the subject has come up I have never yet seen anyone make a convincing case for it being of any value other than as an interesting toy--- watching the ferries for example, to see if they're on schedule-- in the waters we boat in.

And as we couldn't care less if the ferries are running on schedule or not, or what the name of that tanker over there is, it is not a toy we have so far generated any interest in having.

If we ran at night on a regular basis or if much of our boating was done in busy shipping lanes and harbors, AIS would be something we would definitely want.

Last year we upgraded our VHF radio with a Standard Horizon GX 2150 the difference between it and our old radio is night and day. Sound quality and display size (very important these days) is great.

The new radio is also an AIS receiver so of course I took the time and hooked up a USB breakout cable to the laptop running Nobeltec. We have AIS on our charts now, fun to see who is out there and nice to know the names if you need to communicate with them. Would I run out and spend a boat buck on a transceiver, not for the cruising style we do in the Gulf Islands. If we ran in the fog or night a lot then I would would install one so we could be seen.

Sailor of Fortune said:

For those that use Marinetraffic.com , please be aware of certain limitations...to the free version at least.
Many times we will be NOWHERE near where it shows us. Case in point, our chief engineers' wife called the tug and wanted to know why we were only off the New Jersey coast (we had left 4 days prior, heading to the Bahamas). We were actually off of The coast of Florida.
This happens frequently.
A captain I know will unplug his AIS at the dock and move the tug to go grub shopping, get water etc. His supervisor will "see" him on Marine traffic as at the jobsite dock! when he gets back to the job, he re-connects his AIS antenna. Marine traffic is showing the vsl as at the original position.
Keep in mind that these boats use IMO compliant versions of Furuno AIS so it probably not an equipment malfunction. Also, while in New York, we are on the VTS system. So we would know quickly if the AIS wasn't painting the boats signature.

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thanks. I wondered about that cause i would see a vessel on marine traffic.com out fishing only to look up and see the same vessel pass me in the harbor
Hey, is that a picture of you and your crew in your avitar?....If so you have a fine looking crew

My crew is a little scruffier than the ones pictured.The Hooter girls came aboard in Norfolk, Va several years ago. (before my time on the tug!)

SomeSailor said:

DSC only transmits your MMSI, position and a DSC alert message. AIS transmits continuously and sends much more information. Even when not in trouble, your position, bearing, speed, destination, status, callsign, vessel description and is being reported to all around you, as well as the Coast Guard and VTS.

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If you hook your VHF to your GPS, when you press the "little red" button it will also transmit your position....

Sailor of Fortune said:

My crew is a little scruffier than the ones pictured.The Hooter girls came aboard in Norfolk, Va several years ago. (before my time on the tug!)

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Humm.....so they jumped ship when you came aboard!!.........Scruffier?..well then i guess you will have to change the dress code or maybe pay them more so they can afford not to be so scruffy

Alaskan Sea-Duction said:

If you hook your VHF to your GPS, when you press the "little red" button it will also transmit your position....

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I get that, and that's exactly what I said. But it's the things after your "..." that don't get sent. AIS sends data every 30 seconds underway. Much more data than DSC alone contains.

AIS and DSC are two different technologies.

Marin said:

And as we couldn't care less if the ferries are running on schedule or not, or what the name of that tanker over there is,

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I never am interested if that "ferry is running on schedule", but if I am passing across her stern and I see she is getting underway, I know automatically what our two intercept courses are. It's completely automatic, and very handy.

SomeSailor said:

I never am interested if that "ferry is running on schedule", but if I am passing across her stern and I see she is getting underway, I know automatically what our two intercept courses are. It's completely automatic, and very handy.

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so the information you recieve is accurate enough to allow accurate intercept course plots?

so the information you receive is accurate enough to allow accurate intercept course plots?

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On a chartplotter, yes. On a website, no.

... if that was your question.

bfloyd4445 said:

so the information you recieve is accurate enough to allow accurate intercept course plots?

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Yes... And it's done automatically. As soon as he switches from "A" end to "B" end, his bearing reverses and it will project a bearing line and that will trigger a MARPA alarm if you have that set. Same goes for a commercial moving down the middle of the shipping lane. You will get a projection based on his ACTUAL speed and a bearing line off his bow. It's very helpful. Essential... No. Cool... Yes

Rusty said:

On a chartplotter, yes. On a website, no.

... if that was your question.

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I was thinking of a chart plotter. Would radar and ais show the vessel at the same location or would there be some slight diference

SomeSailor said:

I never am interested if that "ferry is running on schedule", but if I am passing across her stern and I see she is getting underway, I know automatically what our two intercept courses are. It's completely automatic, and very handy.

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If you can't eyeball that intercept driving a less than 20 knot vessel.... either visually or on a small radar even without MARPA.... holy cow...especially with your experience...

psneeld said:

If you can't eyeball that intercept driving a less than 20 knot vessel.... either visually or on a small radar even without MARPA.... holy cow...especially with your experience...

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They hold the ferries in their slips with power. When the propwash, turbulence, and foam coming off the "back" of the ferry stops, she's coming out.

Marin said:

They hold the ferries in their slips with power. When the propwash, turbulence, and foam coming off the "back" of the ferry stops, she's coming out.

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Yep...you would think with some posts here we were all driving 30 plus knot guided missle frigates through a tight battle group....or a high speed ferry across the Engilsh channel in the fog and praying that the only targets out there has AIS....

psneeld said:

Yep...you would think with some posts here we were all driving 30 plus knot guided missle frigates through a tight battle group....or a high speed ferry across the Engilsh channel in the fog and praying that the only targets out there has AIS....

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[FONT=Arial, Helvetica, sans-serif]well said. We should start a America's Cup for trawlers. We could have a bunch of different awards, fastest, slowest, etc. I'll even volunteer to be the treasurer cause i already have a calculator.[/FONT]

rwidman said:

Or,
Add to the "have it" group, the ones who find it an interesting toy.

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Remembering, our boats are toys.

sunchaser said:

Remembering, our boats are toys.

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Not for some of us...they are homes, second homes, transportation, offices...etc...etc...

And not all of us go to West Marine and clean of the shelves every time a paycheck comes in...