SailNet Community banner
1 - 20 of 131 Posts

·
Registered
Joined
·
2,214 Posts
Discussion Starter · #1 · (Edited)
I decided to buy an AIS system, to enhance safety in poor visibility and other difficult conditions in the Chesapeake Bay. This is a relatively rare occurrence (I don't go out if it is foggy) but it happens; in some of our violent thunderstorms you can barely see beyond the ends of the boat.

Question is what AIS should I buy.

So far, I have made some decisions but I would appreciate help from the competent people on this forum for some others. Here is what I have decided:

-- It will be AIS-B (duh)
-- It will be an active system, not just a receiver
-- It will have its own antenna, not a splitter. This is based on the arguments by SVAuspicious on S/N, among others. Eventually the antenna may end up on the spreaders, for the time being probably on the pulpit
-- It needs to have an audible alarm, or a connector where I can connect one (I presume that all models have this, but just to make sure...)

To make clear what I do NOT know yet, here is the situation. We are talking a 32' sailboat with somewhat minimal electronics. I have a rather old (90s) VHF (no DSC or anything). And a nearly equally old GPS, a Garmin GPSMAP 162 (black and white, with a screen smaller than my current cell phone). Both work OK for what I do, which is daysailing and occasional overnighters in the Chesapeake. I don't really see a need to replace them, they do all I need. But if there is a good reason to replace them with something else, I have gotten a lot of mileage out of them and would be not be sad to see them go, either.

So, on to the AIS. It seems to me there are three options:

1) Buy a stand-alone system, a transceiver with a dedicated screen for the AIS

2) Buy a 'black box' transceiver and interface it with my existing GPS
(which talks NMEA 0183)

3) Replace the old GPS by a new Multi Function
Display and interface it with a black box AIS transceiver

(is there another one that I overlooked?)

I imagine that (2) is cheapest, (1) is intermediate and (3) is most expensive. I am a cheap person but I hesitate a little bit to add more clutter to the tiny b/w screen on the existing GPS. And I am not really looking forward to messing with 20 year old electronics. So at this point, option (2) is at the bottom of the list.

I am not sure how big the differences really are between the three solutions. And, in general, I appreciate quality products, and if I can get a markedly better product for not much more money, I will take it.

So, my questions to the experts here on S/N:

a) Towards which of these solutions (1, 2 or 3) would you steer me?

b) What are good models for each of them?

This has taken on some urgency since I see that the first announcements
of fall boat-show rebates are out, e.g. Defender:
Marine AIS on Sale
I want to take advantage of the off-season and probably buy this pretty soon.

Muchas gracias for any information!
 

·
Registered
Joined
·
7,213 Posts
Thing you don't tell us is how long you intend to hang on to the boat. If it's for awhile take the plunge and re- up your electronic suite. If you're going to move on go with what will get you by. Other thing you don't say is what type of sailing you do. If you are doing multiple overnights across multiple shipping lanes get the best you can afford. Then you only have to worry about figuring out which way the fishing boats are going. AIS is a blessing on night watches for sure but realize most fish boats don't have it. For poor visibility radar with a good chart plotter maybe more helpful. Really like the dual screen displays. Radar on one chart on the other.
 

·
Administrator
Joined
·
8,365 Posts
I bought the Raymarine 650. Its about $850 so not cheap.

It has a USB plug so goes straight into the laptop running OpenCpn.
It can also go straight into a Raymarine chart plotter.

All AIS have their own GPS. So your laptop then has gps for its plotter.

I agree, and have a separate vhf antenna.

The power consumption is minimal so i have it in 24/7

I hope this helps


Mark
 

·
Registered
Joined
·
2,704 Posts
I decided to buy an AIS system, to enhance safety in poor visibility and other difficult conditions in the Chesapeake Bay. This is a relatively rare occurrence (I don't go out if it is foggy) but it happens; in some of our violent thunderstorms you can barely see beyond the ends of the boat.

Question is what AIS should I buy.
Safety in poor visibility will only be enhanced by AIS if there is a proliferation of other vessels in your area that also have AIS. AIS generally only tells you about vessels that share the system and that are likely to move into your path/area.

Exceptions to this may be some channel markers that use AIS (example: all harbour channel markers in Auckland are AIS equipped) and I don't know what your area is like but in my experience the stationary use of AIS is quite unusual/rare. Your area may differ but it doesn't look to me like the dominant part of the Bay has much commercial shipping

If your area is populated by other recreational vessels without AIS or shoals/reefs/islands/shoreline projections, you should probably be considering radar first.

DISCLAIMER: I don't know anything about Chesapeake Bay - above comments are intended to be generic.
 

·
Once known as Hartley18
Joined
·
5,179 Posts
I bought the Raymarine 650. Its about $850 so not cheap.

It has a USB plug so goes straight into the laptop running OpenCpn.
It can also go straight into a Raymarine chart plotter.
A neat unit indeed! That's what I'd get if I was in the market for one and had the $$$ to spare..

All AIS have their own GPS. So your laptop then has gps for its plotter.
Not true. The GPS is required for transmission of your position to other vessels, so it's generally only the AIS transceivers that have built-in GPS. AIS Receivers (like the Ray 350) generally don't.

Just something to keep in mind when choosing what to buy...
 

·
Registered
Joined
·
2,507 Posts
Hello,

IMHO, for your use, an AIS receiver would be a good idea. I don't think you need a transceiver. Whatever you do get, forget about interfacing it to your old garmin unit. First I doubt it would be able to understand the AIS messages. Even if it did, the screen is so small that it would not be able to display any meaningful information.

Whatever unit you get, I recommend you get one with NMEA 2000 networking. It's SO much easier to connect and configure. You just plug in the wire and you're done. No fiddling with teeny tiny wires and trying to figure out who is the talker and who is the listener and that sort of stuff.

This year I added an AIS receiver to my boat. I bought a Simrad unit, a combo VHF and AIS receiver, one of the few with NMEA 2000. I connected it to my Garmin 740S plotter, and it just works. The plotter displays AIS targets, beeps when it detects a possible collision, and is very easy to use. It's not perfect - if a vessel pops up on the garmin display, I can't automatically hail it by mmsi number, I need to manually enter the number. Kind of dumb but that's the way it works.

Good luck,
Barry
 

·
Administrator
Joined
·
8,365 Posts
Not true. The GPS is required for transmission of your position to other vessels, so it's generally only the AIS transceivers that have built-in GPS. AIS Receivers (like the Ray 350) generally don't.
Yep, I am talking about Class B AIS which is what the OP asked about. The US FCC requires all Class B to have GPS of their own, not integrated with other onboard GPS.

A receiver is neither Class A or B its just a receiver. Which, IMHO, is a waste of money cos it only does half the job, and that half is the one anyone can do with their eyes :) OK, their eyes and a plotting board, compass, pencil, paper, hot chick and beer.
 

·
Registered
Joined
·
5,554 Posts
... It's not perfect - if a vessel pops up on the garmin display, I can't automatically hail it by mmsi number, I need to manually enter the number. Kind of dumb but that's the way it works.
I can't hail from my chartplotter display either, but my SH VHF/AIS does give me a list of nearby vessels (on the radio itself) from which I can hail boats directly without manually entering the MMSI. Are you sure your Simrad doesn't have this capability somewhere in the radio's display?
 

·
Administrator
Joined
·
8,365 Posts
You can't DSC an MMSI from most plotters or laptops. However, I have found calling the ship on VHF with their name always gets a respinse.

If it doesnt and the ship is getting close you can use your VHF to do a DSC All Ships call. That makes an alarm go off on their VHF, and every other ship in range too i.e. Lots of wittnesses! :D

Much quicker to use and All Ships than put in an MMSI to my vhf. Which idiot designed that??


*********BTW My next post will be Acronym, Abbreviation, and Initialisation free! (Except BTW, IMHO, FWIW, YMMV, GGF'd, and any swear word that has a ! Or @ to avoid the Naughty Word checker NWC??)
 

·
Mermaid Hunter
Joined
·
5,686 Posts
-- It will be AIS-B (duh)
-- It will be an active system, not just a receiver
Those two things are the same - if it is AIS-B it is active.

-- It will have its own antenna, not a splitter.
Good choice. I've done a number of these and there are some things you can do to make it easier. I'm happy to help with those details as you progress.

-- It needs to have an audible alarm, or a connector where I can connect one (I presume that all models have this, but just to make sure...)
Alarms are usually a function of the display, so if you choose a black box solution the alarm is on the display.

I have a rather old (90s) VHF (no DSC or anything). And a nearly equally old GPS, a Garmin GPSMAP 162 (black and white, with a screen smaller than my current cell phone).
1) Buy a stand-alone system, a transceiver with a dedicated screen for the AIS

2) Buy a 'black box' transceiver and interface it with my existing GPS
(which talks NMEA 0183)

3) Replace the old GPS by a new Multi Function Display and interface it with a black box AIS transceiver
I don't believe that option 2 exists. The GPSMAP 162 does not, to my knowledge, support AIS.

As others have noted another option (either 4 or 3B) is to put OpenCPN or another navigation tool on a laptop, probably at your nav station, and connect a black box AIS to that.

Someone above asked a good question. How long do you plan to keep the boat?

If you aren't going to keep the boat very long (however long that is), you might consider backing off to an AIS receiver and get an integrated VHF/DSC/AIS. Installation is easy, it gets you information about (most) commercial traffic, and it upgrades your VHF to modern standards.

If you plan to keep the boat through a series of electronic upgrades, you might consider a standalone Class B AIS like the Vesper Watchmate 850. In the near term you can mount it to be visible from the cockpit. Later when you upgrade your GPSMAP 162 you can move the AIS display to the nav station.

Alternatively you could bite the bullet now and upgrade to an MFD and a Raymarine 650, an Em-Trak, or similar Class B transponder.

There are some surprises people get during installation, mostly due to bits and bobs including tools they have to buy. Many DIYers run into trouble because they install something without considering the difficulty or even possibility of cable pulls. If you would like to meet somewhere near Annapolis I'll be happy to give you some pointers.
 

·
Sailboat Reboot
Joined
·
652 Posts
A couple of suggestions:

1) Go out to one of the AIS web sites and zoom in on coverage for your area. Now they pretty much depend on someone having an AIS receiver on shore interfaced to the Internet that covers your cruising area. You may find that there is no real coverage of where you cruise. My experience in the Bay is that the majority of boats do not have AIS, if they do it is receive only (which kind of defeats the purpose since you can't see them.) Try this link for starters http://www.marinetraffic.com/ais/home?level0=100&cb=4879

2) Consider a very inexpensive AIS receiver such as Smart Radio SR161 AIS Receiver. Tying into a chart plotter such as OpenCPN and you will get an idea of what is going on in your area. There are a couple on sale on ebay - lowest price is $60. Not a lot to pay to find out what is going on. If when out sailing you find the AIS plot is pretty much like the visual plot (unlikely) then you can keep if for a backup or put it back up for sale on Ebay.

3) You most likely know this from your research but you will have to get an MMSI should you choose a transceiver. Although you will be tempted to get one via Boat US or similar I strongly recommend you get an FCC radio license (cost about $12 per year.) If you ever take the boat out of the US you will need an international MMSI

Fair winds and following seas :)
 

·
Registered
Joined
·
5,554 Posts
A couple of suggestions:

1) Go out to one of the AIS web sites and zoom in on coverage for your area. Now they pretty much depend on someone having an AIS receiver on shore interfaced to the Internet that covers your cruising area. You may find that there is no real coverage of where you cruise....
This statement is going to confuse a lot of AIS newcomers.

Yes, the display of vessels on the marinetraffic website depends on someone having an AIS receiver interfaced to the internet. They depend on "volunteer" stations feeding their information into their not-so-real-time database, and if there is no such station in your area, their website will be missing lots of vessels.

But that has NOTHING to do with what you will see if you have a real AIS receiver on your boat. A real AIS receiver pulls the AIS transmissions directly from the large commercial traffic that you need to stay away from (and also from those annoying recreational class B transponders). It does not require any Internet coverage, so you will see vessels that the marinetraffic website misses.

All vessels >300 tons are required by SOLAS (international) and US DHS (domestic) to transmit class A AIS signals. So you will see these vessels if they are there. There's no "coverage" issue with this.

If you sail in an area with no commercial traffic, you may not need AIS unless you want to see the recreational boats that have it. If you sail in an area with significant commercial traffic, an AIS receiver will be very helpful. A full AIS transponder will allow you to be seen by other boats. Whether they will steer around you is another issue entirely. But in low visibility situations, it would provide added safety.
 

·
Sailboat Reboot
Joined
·
652 Posts
This statement is going to confuse a lot of AIS newcomers.

Yes, the display of vessels on the marinetraffic website depends on someone having an AIS receiver interfaced to the internet. They depend on "volunteer" stations feeding their information into their not-so-real-time database, and if there is no such station in your area, their website will be missing lots of vessels.

But that has NOTHING to do with what you will see if you have a real AIS receiver on your boat. A real AIS receiver pulls the AIS transmissions directly from the large commercial traffic that you need to stay away from (and also from those annoying recreational class B transponders). It does not require any Internet coverage, so you will see vessels that the marinetraffic website misses..
I see your point and did not want to mislead. My suggestion about going out to an AIS web site (particularly for an area like Baltimore) was that the OP could get a feel for how many boats were not showing up. Now its raining here today (again) in Virginia Beach so there are not a lot of recreational boats out. But my experience here in Virginia Beach is that I see few recreational vessels on my chart plotter at any time. If one's objective is to avoid the slimy little buggers AIS is not much help.

Further - some fishing boats are exempt: From the USCG AIS FAQ web site:

9. Are fishing vessels subject to AIS carriage, and, are onboard Vessel Monitoring Systems (VMS) an acceptable substitute for AIS?

Most fishing vessels are not currently subject to AIS carriage requirements, except for those on International voyage and of 300 gross tonnage (GT ITC) or greater (see 33 CFR 164.46(a)(2)). Note, the fishing vessel exception in 33 CFR 164.46(a)(1) and (a)(3)(i) only applies to fishing vessel' as defined in 46 USC 2101, which means a vessel that "commercially engages in the catching, taking, or harvesting of fish or an activity that can reasonably be expected to result in the catching, taking, or harvesting of fish"; it does not extend to domestic 'fish processing vessels' or 'fish tender vessels' transiting a Vessel Traffic Service area.
(BTW I was surprised by the "and" - my emphasis added)

In my humble experience the vast majority of fishing boats working coastal do not carry AIS. From a navigation standpoint (for me) they are a bigger problem then large ships because (1. They have the right of way over my sailboat if they are actively fishing and 2. They seem to be far more focused on their fishing than on not running into me.)

Finally - close in to port areas the "big boys" don't bother me much. They pretty much stay in the shipping lanes and their actions are mostly predictable.

I am confused about your reference to the "annoying recreational class "B" transponders. Would you care to elaborate?

Fair winds and following seas :)
 

·
Registered
Joined
·
5,554 Posts
I see your point and did not want to mislead...
I figured that. It didn't seem intentional.

...I am confused about your reference to the "annoying recreational class "B" transponders. Would you care to elaborate?
Sorry, my personal preferences were sneaking into my post.

I daysail on the Delaware River where there's a lot of commercial shipping traffic. There are parts of the river where the channel covers the entire width of the river, so you can't stay out of the channel all the time. So I really want to see the big guys on AIS so I can tell how fast they're going and how much time I have to get out of their way. It's hard to judge those things when they're 2-3 nm away. But it's good to know ahead of time so you're not guessing. It also affects my decisions about which side of the river get to when I'm getting out of the channel. In some places I might get "pinned" between channel and the shore (or skinny water) and that combined with swift tidal currents could spell disaster. So with AIS I get a huge amount of information that I can use to time my tacks to stay out of their way.

Around here, almost no recreational boats have AIS. On the upper Chesapeake (Elk River, Turkey Point, etc.), it seems like a lot of them do. It annoys me because it clutters the screen and distracts me from the bigger boats that I really care about. In that area there is large commercial traffic also, since it's near the canal entrance.

In general, I want to see the stand-on vessels (class A transponders), and I'd prefer not to see the give-way vessels. Those recreational boats (class B transponders) are all give-way vs. a sailboat. I don't fool myself into thinking that they actually know the rules of the road, but for the recreational boats I'm just as happy to see them with my eyes instead of having them clutter up my screen. For me, that's only an issue when I go down into the upper Bay.
 

·
Sailboat Reboot
Joined
·
652 Posts
I want to see the stand-on vessels (class A transponders), and I'd prefer not to see the give-way vessels. Those recreational boats (class B transponders) are all give-way vs. a sailboat.
Good conversation but I think that you have been unintentionally misleading.

Other than the famous "law of gross tonnage" (get out of the way of anything bigger than you) large ships are not the "stand on vessel." COLREGS Rule 9 applies "along the course of a narrow channel or fairway." It requires

A vessel of less than 20 meters in length or a sailing vessel shall not impede the passage of a vessel [ which | that ] can safely navigate only within a narrow channel or fairway.

"A vessel proceeding along the course of a narrow channel or fairway shall keep as near to the outer limit of the channel or fairway which lies on her starboard side as is safe and practicable."

A big ship has no more right to barrel down the center of the channel than you do nor do they have the right to endanger your vessel by pushing you into shoal water.

Now what is interesting is the "narrow channel" is not explicitly defined. See page 3 of http://www.law.washington.edu/Direc...ations/Article_2010_Allen_Narrow Channels.pdf.

Outside of a "narrow channel or fairway" sailboats have the right of way. Common courtesy suggests that getting your more agile sailboat out the way of a 1,000 ft long ship is a good idea even outside of a "narrow channel or fairway" if you can do it safely.

In the open ocean my experience is that the reverse frequently happens. Usually AIS is the first contact between a large ship and a small sailboat. It is much more reliable then the ship seeing the sailboat on radar. Since open ocean meetings are rare I have taken to contacting the ship on VHF. Usually I just say - "want to make sure you see me" since I don't know if anyone is actually looking at their AIS plot. The most frequent response (after a long pause) is "yes, we have you, maintain course and speed and we will avoid you." If the CPA is less than a mile usually the ship will alter course to open the CPA to at least a mile. This works for me as I am most likely sailing with a wind steering device and preventers.

Of course if it is a Carnival Cruise Line ship I immediately run like hell out of their way. Carnival's Captain's motto seems to be "we turn for nobody!"

Fair winds and following seas :)
 

·
Registered
Joined
·
5,554 Posts
Good conversation but I think that you have been unintentionally misleading.

Other than the famous "law of gross tonnage" (get out of the way of anything bigger than you) large ships are not the "stand on vessel."...A big ship has no more right to barrel down the center of the channel than you do nor do they have the right to endanger your vessel by pushing you into shoal water...
I choose to stay out of their way where I sail. I'm not going to engage in an argument over this - there are plenty of other threads where you can find and join those arguments. I have no interest in being "dead right."
...Outside of a "narrow channel or fairway" sailboats have the right of way.
I had been taught that the term "right of way" has pretty much been retired and replaced by "stand on." No vessel ever has right of way, since collision avoidance ultimately supersedes that right.
 

·
Administrator
Joined
·
8,365 Posts
Of course if it is a Carnival Cruise Line ship I immediately run like hell out of their way. Carnival's Captain's motto seems to be "we turn for nobody!"
Don't be ridiculous! Outside Disney cruise ships, Carnival has the largest outdoor video screens... You can only watch the show if you are close up, and can only hear if you are even closer.

AIS gives a great advantage to be able to close the CPA to maximise video viewing time.

Last overnighter I saw Mickeys whole performance! A squall prevented me seeing Minnie's encore :(

Mark
 

·
Sailboat Reboot
Joined
·
652 Posts
I choose to stay out of their way where I sail.
So do I!!! If you inferred otherwise my apologies. The paperwork is a *****!

On a side note: apparently the maritime courts never find either vessel "scot free." Which, on a side note to the side note, has nothing to do with Scotland. Apparently scot free is old English for tax free. Since ultimately the responsibility to avoid collision is equally shared by both vessels the courts always find some blame for the actions of both vessels.

But I totally agree. Tis a far far better thing to avoid them then to argue from the water while hopefully wearing your life jacket.

Fair winds and following seas :)
 

·
Registered
Joined
·
2,214 Posts
Discussion Starter · #19 ·
Thing you don't tell us is how long you intend to hang on to the boat. If it's for awhile take the plunge and re- up your electronic suite. If you're going to move on go with what will get you by. Other thing you don't say is what type of sailing you do. If you are doing multiple overnights across multiple shipping lanes get the best you can afford. Then you only have to worry about figuring out which way the fishing boats are going. AIS is a blessing on night watches for sure but realize most fish boats don't have it. For poor visibility radar with a good chart plotter maybe more helpful. Really like the dual screen displays. Radar on one chart on the other.
Right, I did not say how long I will stay with the boat. I have no intention to sell her for at least several years.

OTOH, I don't see why I should rip out perfectly working equipment (existing VHF, GPS) just because it is old. This is not a reason for me. If there is a good reason for it (like I want to interface with AIS and the old stuff cannot do it), then THAT would be reason.

As for type of sailing, as I said, daysailing and some overnighters. I considered radar (I even have some training on radar equipment) but it is more money and I think that AIS does all I need. Which is, getting out of the way of the real big boyz.

I am well-aware that fishing vessels and recreational boats usually do not have AIS.
 

·
Registered
Joined
·
2,214 Posts
Discussion Starter · #20 ·
I bought the Raymarine 650. Its about $850 so not cheap.

It has a USB plug so goes straight into the laptop running OpenCpn.
It can also go straight into a Raymarine chart plotter.

All AIS have their own GPS. So your laptop then has gps for its plotter.

I agree, and have a separate vhf antenna.

The power consumption is minimal so i have it in 24/7

I hope this helps

Mark
Yes, it helps, Mark. I am starting a file with recommended models, the Raymarine 650 is the first entry. Thanks.
 
1 - 20 of 131 Posts
Top