Talk to me about AIS.

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Al

Guru
Joined
Apr 1, 2012
Messages
2,206
Location
usa
Vessel Name
'SLO'~BELLE
Vessel Make
1978 Marben-27' Flybridge Trawler(extended to 30 feet) Pilothouse Pocket Cruiser[
Have become enchanted with AIS. Having the program on my phone allowing me to view the vessels about with this feature holds my attention.
I can see this as substitute for "SPOT" in terms of the wife following my voyages on her notebook. As I travel in blind spots for cell service, being able to view my position seems a no brainier. Other than having this option on my phone I would really like to hear the pros and cons, size of unit, requirements of space, cost, and depth of technology required to make the installation.
Is is practicable for a small boat such as our at 28 feet? Are there restrictions on who can or can not utilize? Just a few of the questions. If there is a primer on the subject on line that one could review?

Thanks, Al
 
At its simplest, AIS is available in either class "A" or "B." For your purposes "B" would probably suffice, IMHO.
 
AIS operates on the VHF band so depending on your cruising area, while other vessels can 'see' you, there may be no stations retransmitting your ID for your wife follow on the internet sites.

I have a delorme satellite gizmo mostly for Mission Control's peace of mind, and if I remember to pocket it when going ashore, she can even see which pub we are at.
 
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Stand-alone AIS transponder/receiver systems" are rather expensive.

AIS data are transmitted on 2 VHF frequencies.
Seeing you already have a VHF radio on your yacht, there is no point in duplication by buying a dedicated ais receiver.

To visualize the data, all you need is an additional rc-circuit added to your VHF radio and some decoding software for your laptop.
Then connect the VHF to your laptop for tracking and navigating in real time.

now this is not how I did it I used a Garmin AIS 600 through my NMEA it can then run to any of the screens in the boat including my tv
 
Wikipedia might be the first place to go to. Try this:

https://en.wikipedia.org/wiki/Automatic_Identification_System

In a nutshell, there are varying types and degrees of AIS. There are receive only units and there are full transceivers that also broadcast your position with the transceiver being about twice the cost.

Then there is packaging and display. Some of the AIS's are the size and footprint of a VHF radio. Some are designed into VHF radios. The displays are rather small and challenging. Other units are more like a GPS and have GPS built in and GPS style color displays. Then there are "black box" units without displays. They are normally used with a NMEA 2000 network and a multifunction display. In most cases this is the most useful approach.

All AIS's require a VHF antenna connection.

For your wife to track you on her laptop, you have to be in range of a retransmission facility. This may change in the future as more AIS satellite systems are deployed. AIS is still evolving but it will probably be as universal as GPS in a few years. A keen observer will recognize GPS and AIS share a lot in common and really should be integrated.
 
Have AIS on both of my boats. One is a Simrad stand alone about $1200 with it's own antenna. The other is a West Marine unit that is interfaced through a network (not the nmea 2000) cable to my Garmin plotter. While the unit through my Garmin plotter is very nice, it requires me to leave the plotter on at night to have the AIS active at anchor. The Simrad on my charter boat can be on while the rest are turned off to save the battery. Typically I leave the AIS, VHF, and a simple GPS with anchor watch, while anchored doing diving charters. In my area, land station coverage is poor. I may go more than a month without being picked up by a land station. This is with a top quality AIS antenna on a 14' mast. I routinely pick up ships at 60 miles and can be seen at 30 to 40 miles.

In summary, I like my unit displayed on the garmin chartplotter. I like that I don't have to leave the suite of electronics on with my stand alone at night. Currently AIS is a poor tracking device for land based admirals.

Ted
 
Before my trip down the Louisiana ICW I was advised by Dimer2 to install AIS so the tugs pushing the long barges could se me coming around corners, and also so I could see them coming and adjust my position if needed.

It has worked out very well, and it has made things much easier on me. A few barge captains have been surprised that a recreational boat had AIS and they told me they thought it was a great idea.

I bought a "cheap" Sitex transponder unit for around $500. I also bought a good antenna splitter ($250 Vesper Marine)so I could use my existing VHF antenna and because I didn't feel like running more cable through my crowded wire chase.

It was an expensive add on but well worth it in my opinion.
 
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AIS Website

Interested in which AIS website members are using to follow vessel traffic. Would like my family to be able to locate our boat and track our voyage.
 
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Have become enchanted with AIS. Having the program on my phone allowing me to view the vessels about with this feature holds my attention.
I can see this as substitute for "SPOT" in terms of the wife following my voyages on her notebook. As I travel in blind spots for cell service, being able to view my position seems a no brainier.

The AIS web sites are only as good as the receiving stations. I've found that each of the three or so "big" web sites uses a different network of ground-based receivers, so you can never be sure which, if any, you might show up on.

There's usually good coverage around big harbors. After that, only one or two networks may cover the medium-sized harbors. Outside the harbors, coverage goes from spotty to non-existent.

I typically want to go places the big ships don't. Places where there's no interest in an AIS receiving station.

I have an AIS Class B transceiver and it's great. I'd recommend it. But not for letting folks back on shore know where you are. I ended up buying the Delorme InReach for that.
 
Maybe this should be combined with the other thread on this topic?

Here are three more sites that display live AIS data: VesselFinder, FindShip and FleetMon.
 
Thanks for the replies. I think it is a good idea to combine this thread with the other on AIS--but I don't know how to do that :) Suggestions appreciated.
I've looked at a couple of websites and some seem to display more targets than others--some have ability to filter the type of vessel one is seeking. Was wondering if there is consensus about the best place to go on a home computer to track the boat.
 
Thanks for the replies. I think it is a good idea to combine this thread with the other on AIS--but I don't know how to do that :) Suggestions appreciated.
I've looked at a couple of websites and some seem to display more targets than others--some have ability to filter the type of vessel one is seeking. Was wondering if there is consensus about the best place to go on a home computer to track the boat.
Another thing to keep in mind is that a Class B AIS unit will only be picked up in areas where coverage is provided by a volunteer land based receiver. They are also less powerful than the Class A commercial units.
We recently took a trip from Muskegon MI to Sturgeon Bay WS and back. We showed up on only about a third of the trip. And somewhat intermittently even then.
You don't want to create more anxiety, so please make sure your friends and family are aware it is not perfect. SPOT or something similar may be more useful.
 
As a commercial guy, it certainly makes it much easier for us to see you if you have AIS. Sometimes in the middle of the night, when there's heavy rain washing out the radar, that might be the only way I know you're there.
 
The AIS web sites are only as good as the receiving stations. I've found that each of the three or so "big" web sites uses a different network of ground-based receivers, so you can never be sure which, if any, you might show up on.

There's usually good coverage around big harbors. After that, only one or two networks may cover the medium-sized harbors. Outside the harbors, coverage goes from spotty to non-existent.

I typically want to go places the big ships don't. Places where there's no interest in an AIS receiving station.

I have an AIS Class B transceiver and it's great. I'd recommend it. But not for letting folks back on shore know where you are. I ended up buying the Delorme InReach for that.

Dawdler,

I think you should read Capt Tom's post again.

If your main concern is family and friends tracking you, That's not the strong point of AIS and even less so virtual AIS.

I've used all three and the Delorme InReach can't be beat for they purpose.
 
We use a Garmin class B AIS 300 connected between the VHF and antenna, its information is connected to our Garmin 740s through NMEA and it overlays targets on it.
 
In my opinion AIS is a device that is effectively used for collision avoidance. I use mine for that purpose and it has been a major tool in that resource box. It has not only provided real time information on the Rivers but also well offshore. If you are purchasing it for use as a means of someone on land easily locating your position you will most likely be disappointed, especially offshore. If that is your reasoning for the purchase it would probably be easier to just have those on land track your phone with "where is my phone".
dan
 
Al,

I don't think putting an AIS Class B transponder on your boat will allow many people to track you over the internet. Once you get out of the channel in Ketchikan I dare say no one is receiving AIS transmissions and posting them. Your Spot or InReach is the best device.

Tom
 
Try SiiTech.....Login
Other devices (Spot) have you for sure
 

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I probably wasn't clear enough in my original post. I already have AIS on board as an information/collision avoidance tool. That's its primary purpose and it is terrific for that. However, there appear to be several websites that allow folks at home to "watch" what's going on. This is a nice side benefit albeit with some limitations as have been discussed. In cursory investigation I saw some differences among sites, and was wondering if the TF members found any of the websites superior to others in coverage, ease of use, functionality, etc. So again, any preference for AIS monitoring websites?
 
You have to first get an mmsi number. Then you buy the AIS transmit and receive unit. The unit is supposed to be programmed by a licensed person with your mmsi number. Then you can install it. Vessel size does not matter. Just read your last post after sending. YOUR antenna makes all the difference in shore stations picking up your info. ( unless you are near a ship that is rebroadcasting info to one of the websites). I routinely see vessels that are visible that suddenly 'appear' on ais display. Some do not show up until VERY close.
Not all installations are equal.

Regarding which websites to use both at home and on phone: Generally anything that is 'free' is based upon traffic info within range of repeater stations on land. OR (as in marine traffic) boats who rebroadcast nearby vessels info and send that to marine traffic. The 'pay' sites use a combination of land based, antenna satellite based and rebroadcast info. If you pay you usually get better data.

I know my office pays 100 a month. But they want no delay, up to date infinite coverage everywhere. Personally I find the free info useful enough for my use. I use marine traffic.
 
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Just evaluate what you really want out of the gear.....there are some ways to track a vessel for those at home and there is collision avoidance.

Even AIS doesn't help for probably 90 percent of the traffic the average received boat encounters. It is great for some situations..but if you avoid areas of high commercial traffic, much less useful.

So if unlimited budget get it for no other reason it is a good tool..if not, pick your poison.
 
Tom (tpbrady)
Good to hear from you. I know you to be up on this electronic stuff and I believe you understand that I on the other hand am about "Smoke Signal" qualified!

I use Marine Traffic and find that the traffic reported is darn close to being on the mark for now time current location. I have a SPOT devise but have not activated the unit as the voyages are spasmodic at best with the question of annual subscription value.

The thinking of having with a one time AIS equipment expense on board and the Marine Traffic app on the wife's computer would be a straight forward accomplishment.

Once a boater is about 15 miles away from say Wrangell in this case, my most travled voyage, there is no longer any cell service hence, no internet via a UBS connection (I think that is the correct verbiage ) and not till one is nearing Meyers Chuck will cell service be reestablished. As that 30 miles of no coverage is the cusp of "Go or No Go" decision, prior to the normal weather and sea condition, having the wife know why I am not phoning in would count.

It may be that the SPOT is the better decision cost not considered a factor in the long run.
Thanks for your response and those who contributed.
Al
 
A lot of good info here.

WHY AIS? It is just another tool in your toolbox to make your cruising more enjoyable and safer. Period. Do you need it? Depends on your cruising style.

I upgraded my boat this last winter with all Raymarine equipment. Radar, MFD and AIS. I will be cruising the PNW, SE Alaska and I view AIS and just another safety feature. AIS cost me about $700 (unit and new VHF/AIS antenna) for transceiver Class B (Meaning I transmit and receive). Cheap insurance to aid in use with your chartplotter and radar.

Do you need it maybe not, but I have been in the thick fog, saw a tug/tow on my radar and was able to identify and call the tug by name because of AIS to avoid a collision. The USCG is also installing some AIS transmitters on buoys now.
 
I probably wasn't clear enough in my original post. I already have AIS on board as an information/collision avoidance tool. That's its primary purpose and it is terrific for that. However, there appear to be several websites that allow folks at home to "watch" what's going on. This is a nice side benefit albeit with some limitations as have been discussed. In cursory investigation I saw some differences among sites, and was wondering if the TF members found any of the websites superior to others in coverage, ease of use, functionality, etc. So again, any preference for AIS monitoring websites?


The short answer is, the AIS websites are limited, especially so in remote areas. The Delorme "Inreach" satellite transmitters are way more reliable and also permit texting to family and friends. It is not affected by high terrain, or other limitations of AIS. I have one and it is the primary means for us to communicate with family. The primary value of AIS is to provide identification, speed and course to other vessels in your vicinity, to aid in collision avoidance.

We had difficulties with the installation of our Class B AIS. It is affected by other boats in the marinas, whether you are moving or not, and has many of the same limitations of VHF. AIS is essentially a VHF that Tweets where you are. It's range is limited. Only large ships with tall antennae (and Class A) can broadcast signals more than 8-10 nm.


Jim
Sent from my iPad using Trawler Forum
 
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Had an opportunity to speak to a boater with AIS on board. He is a boater out of Texas who had the unit on board prior to coming to Alaska via Anacortes, Wash. I found him on Marine Traffic as he passed the house this morning. Followed him on AIS to a local fuel dock. I explained my dilemma on being in blind spots and give a specific area of concern. His response was fortuitous, He had just traveled down that same route and found that he was not being followed or seen by AIS . Therefore, in our conversation the agreement was that SPOT would be the more positive process to accomplish what I desire. I am proceeding on that venue.
Will give a follow up on what develops with the SPOT discussion scheduled with our local rescue squad leader for tomorrow. Stay tuned-

Appreciate all the responses to the inquiry to this point.
Al
 
@Al
It would depend on what your complete intentions are regarding AIS use and visibility. Individual SPOT phones only communicate with home base (or whoever you chose to share with). AIS communicates with anyone else within range (especially a shore bases repeater). If you opt for spot you will never be seen by anyone else on a boat for navigation purposes.

The coverage gaps of AIS communication due to terrain or poor antenna installation we all have to live with. If we operate where there are no base stations that rebroadcast to marine traffic (or the like) then we have no visibility to others trying to look at us unless they are in range.

My boat has AIS. If I were voyaging afar I would probably get a spot myself. But, they are for two different purposes.
 
Will give a follow up on what develops with the SPOT discussion scheduled with our local rescue squad leader for tomorrow. Stay tuned-

I'm glad you finally heard some first-hand experience about the limitations of shoreside AIS.

If you don't mind my asking, what lead you toward SPOT as opposed to the Delorme InReach?

The SPOT is cheaper, and although the coverage is slightly less than the 100% InReach offers, for most coastal cruisers that's not an issue.

I went with InReach because it can send and receive ad-hoc text messages, and because I can pay for service plans by the month, and suspend the service altogether when I don't need it (after paying an annual activation fee.) Besides keeping the crew and family back home happy, the two-way text is a nice safety feature, as a backup to the EPIRB, PLB and multiple VHFs we already carry.

[edit] I just realized I didn't even mention AIS. I carry a Class B transceiver, but I don't consider it an emergency communications device OR a reliable way for folks back home to track us.
 
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I enjoyed speaking with Al in Ketchikan. The issue with AIS is with Marine Traffic as Al wanted to use it. Marine Traffic depends upon land based receivers to collect AIS information and post it on their web site. That is why you do not have complete coverage in the outlying areas outside of major population centers that have people that set up land based AIS receivers.

I suggested that for Al's application to let his wife know where he was, the SPOT or similar product would work better for him. I know that Delorme has another product, I just happen to have the Spot. For us we have it programmed to send an email to 8 email addresses (family members, etc.) The programmed message states that "All OK, just wanted to let you know where we are" the link will take them to a map showing our GPS location. All we have to do in the boat is turn the Spot on and press the "OK" button and leave it on until it finds the satellite and sends the email.

We love our AIS in the boat though. With it I can see most commercial shipping (A) and a great number of private personal boats (B). And they can see me. We were advised by a Tug operator on the Gulf Coast to add it to our boat so that the Tugs could see us and we see them especially. AIS works around bends and a much greater distance than radar. Great safety addition to a cruising boat....JMHO.
 
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