AIS Pros & Cons?

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RULE 5

Look-out

Every vessel shall at all times maintain a proper look-out by sight and hearing as well as by all available means appropriate in the prevailing circumstances and conditions so as to make a full appraisal of the situation and of the risk of collision.

I believe AIS Is included in "by all available means appropriate" but does not exempt one from posting a look out.
 
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Do you really believe what you are saying? :rofl: :facepalm:
Pity the boats in front of you who without AIS will let you run into them

Why such a snarky response? Having a bad day today? :ermm:

Yes, the reason to have AIS is so other boats can see your boat, especially in poor visibility or where land masses or trees block the view. I'm sorry you don't seem to understand this, but think about it for a while and it might come to you.

With AIS, others can not only "see" your boat on their screen, they know the name of your boat in case they need to call you. They can also see the speed and direction of travel and will receive a warning if your boat and their boat are on a collision course. It's way better than listening for "small beige trawler near marker 89".

I have personally been called by (the boat's) name by other vessels to clarify passing situations or potential dangers and I have used AIS to determine whether I needed to alter course or remain on course with a commercial vessel approaching from my starboard side.

I have use it many times to determine the name of a (usually sailboat) that I want to pass but has the name on the stern covered by a dinghy.

And (a convenience, not safety related), my friends can follow us on our cruises one marinetraffic.com and I can see exactly where my boat is in the marina when I am at home.

An AIS system is pretty inexpensive as far as boat accessories go. I have never regretted or even questioned my decision to install it. And I would like to see every boat over 30' have it.
 
The Garmin unit I bought, you can download the programming app. It was easy to program, a lot easier than the Flight Management Computers I have programmed for 747s
Same with my emTrak system, I was able to flash it myself with a little programming file emailed to me from the vendor. Can't do it entirely yourself, but pretty close.
 
For clarity, the ban on programming the MMSI number into an AIS unit is a US specific rule only.

In Australia, once AMSA (Australian Maritime Safety Authority) issues the MMSI number, you can connect to the AIS unit via USB and run an application to program the MMSI number and all relevant vessel details by yourself.
 
RULE 5

Look-out

Every vessel shall at all times maintain a proper look-out by sight and hearing as well as by all available means appropriate in the prevailing circumstances and conditions so as to make a full appraisal of the situation and of the risk of collision.

I believe AIS Is included in "by all available means appropriate" but does not exempt one from posting a look out.

Absolutely true, but if you don’t have an AIS then it isn’t available.
 
I was on the fence about adding an AIS transceiver. Only when an AIS built into a VHF radio did I finally install one. Navico (Simrad or B&G), released the RS40B, which combines AIS and VHF into one unit. Installation is simplified and no "network" is needed. I did have to program the unit myself. Called the dealer, Hodges, to confirm this. It is now possible to have an AIS transceiver on even small vessels. An extra antenna was still needed. The unit is wired to my chart plotter, so I can see the targets. It is comforting to know they can also see me. Being right next to the Port of Baltimore, I want the commercial traffic to see me. Despite my limited knowledge of marine electronics, I was able to get the system to work.

Daniel

'89 Tradewinds 43' MY
 
Remember NAVRULEs #5 also discusses "circumstances and prevailing conditions". That is the loophole that allows small vessel skippers with a single watchstander who is also the lookout the flexibility of NOT using electronics 100% of the time.

In a car, fiddling with the radio or texting (eyes off the road) is considered distracted driving. Isn't it just the same as a boat? Most skippers are far less experienced at boating than driving a car. True most boats travel much slower so there should be time to absorb electronic input, but that is still subject to human error, seen all the time in the news.

Don't get me wrong.... using AIS and RADAR well can make one a hyper alert skipper/watchstander possibly safer.... but one has to be familiar with that gear and still be competent when it is unavailable for whatever reason.
 
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Yesterday I was shocked that a sailboater answered a hail on the VHF ch 16. It went like this.
Freighter: sailboat in Georgia strait x3, this is the freighter in the shipping lane heading your way.
Sailboat: Yes I see you but you are far enough that we have time to cross in front of you.
Freighter: Sir we are in the shipping lane and cannot alter course. We have you on a collision course if you do not stop and turn around.
Sailboater: are you sure, looks like we can make it
Freighter: Yes we are sure
Sailboater: OK we are turning around.

No name of the sailboat was used, guess no AIS, but they answered the vhf.
Happy ending
 
Why such a snarky response? Having a bad day today?

Yes, the reason to have AIS is so other boats can see your boat, especially in poor visibility or where land masses or trees block the view. I'm sorry you don't seem to understand this, but think about it for a while and it might come to you.

With AIS, others can not only "see" your boat on their screen, they know the name of your boat in case they need to call you. They can also see the speed and direction of travel and will receive a warning if your boat and their boat are on a collision course. It's way better than listening for "small beige trawler near marker 89".
Too much reliance on electronics. Dont worry about running into me I can see you coming day or night.
This thread or another I mentioned having AIS on a charter, so I was spending a lot of time picking out boats from the dots on the screen.
Most boats appeared where they were shown on the screen, but a few were shown where they were, not where they are. I confirmed that when a boat I was watching on screen and with eyes come closer and when they were abeam 9 oclock of us the AIS had them about 1030. In fog that would not be great.

AIS is a tool, use it but use your senses more.
 
If you set your AIS to ignore slow or stopped boats, you will not see anchored boats. You are turning off part of the safety features of AIS.

Some AIS systems like my Vesper, allow you you use target speed as one of several alarm thresholds. I see the targets stationary but, no proximity or heading alarm.
 
Yesterday I was shocked that a sailboater answered a hail on the VHF ch 16. It went like this.
Freighter: sailboat in Georgia strait x3, this is the freighter in the shipping lane heading your way.
Sailboat: Yes I see you but you are far enough that we have time to cross in front of you.
Freighter: Sir we are in the shipping lane and cannot alter course. We have you on a collision course if you do not stop and turn around.
Sailboater: are you sure, looks like we can make it
Freighter: Yes we are sure
Sailboater: OK we are turning around.

No name of the sailboat was used, guess no AIS, but they answered the vhf.
Happy ending

I know many boaters stink at relative motion...just look how they dock. :eek:

Ships at speed can be tough to estimate but for the life of me, why people don't grasp constant bearing, decreasing range (whether visual or on radar), to determine possible collision is beyond me.

Experience has taught me one thing....not everyone should operate machinery, and many of them can't even be taught to.

I for the life of me can't understand the basics of music....can't seem to hear what others hear.... but the slightest difference in sound while underway perks me right up.....however, my point is don't try to make me a songwriter and some should never graduate past very basic boating or only ride with a friend. ;)
 
Too much reliance on electronics. Dont worry about running into me I can see you coming day or night.
This thread or another I mentioned having AIS on a charter, so I was spending a lot of time picking out boats from the dots on the screen.
Most boats appeared where they were shown on the screen, but a few were shown where they were, not where they are. I confirmed that when a boat I was watching on screen and with eyes come closer and when they were abeam 9 oclock of us the AIS had them about 1030. In fog that would not be great.

AIS is a tool, use it but use your senses more.


That just proves the point that no single tool is reliably able to give you the entire picture. But a collection of what you can see with your eyes (if there's adequate visibility), what AIS tells you and what radar can tell you can put together a pretty complete picture of what's going on around you.
 
Too much reliance on electronics. Dont worry about running into me I can see you coming day or night.
This thread or another I mentioned having AIS on a charter, so I was spending a lot of time picking out boats from the dots on the screen.
Most boats appeared where they were shown on the screen, but a few were shown where they were, not where they are. I confirmed that when a boat I was watching on screen and with eyes come closer and when they were abeam 9 oclock of us the AIS had them about 1030. In fog that would not be great.

AIS is a tool, use it but use your senses more.



AIS is a valuable tool and, of course should be used as one of the many tools available to a vessel operator.

As for you experience with vessels being displayed "where they were", this happens when using an "app" such as marinetraffic.com, but cannot happen when using an actual AIS receiver which receives signals directly from other vessels, not through the Internet.

If you want to make fun of people who believe AIS is a valuable safety device on a boat, I can't stop you, but you seem to be in the minority here.
 
In my experience in the ICW, I had boats abeam me when REAL TIME AIS was reporting them still ahead or behind. I checked this several times right after I had read similar reports on the net, maybe even some on TF.

I think it depends on the class AIS and the speeds involved and if turning sharp and often, but at least a few years back there was a delay. Possibly corrected on newer AIS but if you and the other guy have older models.....maybe....

Ay greater distances, the relative positions would seem more correct, but in close distances they are very apparent.
 
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As for you experience with vessels being displayed "where they were", this happens when using an "app" such as marinetraffic.com, but cannot happen when using an actual AIS receiver which receives signals directly from other vessels, not through the Internet.


In my experience in the ICW, I had boats abeam me when REAL TIME AIS was reporting them still ahead or behind. I checked this several times right after I had read similar reports on the net, maybe even some on TF.

I think it depends on the class AIS and the speeds involved, but at least a few years back there was a delay. Possibly corrected on newer AIS but if you and the other guy have older models.....maybe....

Ay greater distances, the relative positions would seem more correct, but in close distances they are very apparent.


We've seen that too. I think Class B transmit intervals aren't always timely enough, relative to the speed of the transmitting vessel. Don't know if Class B+ is better or not, or if it is, how much.

Once we watched (eyeballs) a smallish express cruiser cross our path while moving at a decent clip. Their last "previous" AIS transmission put them at about 11 o'clock, a half mile ahead of us. Where they were. Their "next" AIS transmission caught up with them at about 3 o'clock, two miles away from us (approx. measured by radar).


Hopefully, nobody is using only AIS to monitor nearby boats, it's a tool, along with eyes and ears.

Indeed.

-Chris
 
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AIS doesn't transmit a boat's position continuously. If I remember correctly, class B (recreational) transmits every three minutes. This might produce a "delay" for a boat making 40 knots, but not a significant delay for a boat moving at 7 knots or so.

Hopefully, nobody is using only AIS to monitor nearby boats, it's a tool, along with eyes and ears.
 
The frequency of transmission depends on boat speed and AIS type. Class B updates location every 30 seconds if you're above 2 kts. B+ will update every 30 seconds from 2 - 14 kts, every 15 seconds from 14 - 23 kts, every 5 seconds above 23 kts. Class A can update as frequently as every 2 seconds depending on speed and whether you're turning or going straight.



USCG_AIS_types_aPanbo.jpg
 
2 boats approaching each other at 7.5 knots each (closure speed 15 knots) cover ) 0.75 miles in 3 minutes. Closure rate and angle of closure.... not speed... is everything in collisions.

In limited vis and/or confined waters...that to me isn't much of a safety margin.

Thankfully it is every 30 sec but that still is an 1/8 of a mile.

Well over 2 football fields) for Class Bs.
 
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Please don't mandate AIS transceivers. I am just moving out of the 18th century and getting used to chartplotters. I did stow my semaphore flags back in the '80's when I purchased a vhf radio. I have never had an autopilot though have installed quite a few back in the day. I just use a line loosely attached to helm so I can view surroundings with binoculars. Whatever happened to security calls when approaching blind and or tight situations?
 
Yesterday I was shocked that a sailboater answered a hail on the VHF ch 16. It went like this.
Freighter: sailboat in Georgia strait x3, this is the freighter in the shipping lane heading your way.
Sailboat: Yes I see you but you are far enough that we have time to cross in front of you.
Freighter: Sir we are in the shipping lane and cannot alter course. We have you on a collision course if you do not stop and turn around.
Sailboater: are you sure, looks like we can make it
Freighter: Yes we are sure
Sailboater: OK we are turning around.

No name of the sailboat was used, guess no AIS, but they answered the vhf.
Happy ending

If the sailboat was equipped with AIS, this whole exercise could have been avoided as the captain would have known that he was on a collision course with the freighter instead of guessing that the freighter was far enough that there was enough time that he can cross in front of it.
 
If the sailboat was equipped with AIS, this whole exercise could have been avoided as the captain would have known that he was on a collision course with the freighter instead of guessing that the freighter was far enough that there was enough time that he can cross in front of it.

Radar would have done the same... or a good skippers eyeballs/brain.
 
Radar would have done the same... or a good skippers eyeballs/brain.

I agree. But the point of the poster was that it went well without AIS and I wanted to point out that it would have gone better with it.
 
The frequency of transmission depends on boat speed and AIS type. Class B updates location every 30 seconds if you're above 2 kts. B+ will update every 30 seconds from 2 - 14 kts, every 15 seconds from 14 - 23 kts, every 5 seconds above 23 kts. Class A can update as frequently as every 2 seconds depending on speed and whether you're turning or going straight.


I wonder if those might be aspirational update frequencies. Best case? Or perhaps interrupt-able (?) by some other circumstance?

The example I cited was in the neighborhood of 3 minutes, IIRC. (Been a while, though...)

-Chris
 
I agree. But the point of the poster was that it went well without AIS and I wanted to point out that it would have gone better with it.

Curious, have you ever owned a sailboat? I said I was shocked a sailboater answered a hail on 16. Why, because the skipper and crew are in the cockpit with wind whistleing through their ears and seldom have a VHF in the cockpit let alone a AIS display in the sunshine. Sailboaters usually do not have it turned on as they cannot hear it from below at the nav station.
Experience would have told you that.
 
Curious, have you ever owned a sailboat? I said I was shocked a sailboater answered a hail on 16. Why, because the skipper and crew are in the cockpit with wind whistleing through their ears and seldom have a VHF in the cockpit let alone a AIS display in the sunshine. Sailboaters usually do not have it turned on as they cannot hear it from below at the nav station.
Experience would have told you that.

Even if the VHF may be a bit hard to hear from the cockpit, my experience says that the majority of sailors are pretty good about having it turned on. On the other hand, outside of boats that are obviously doing long distance cruising, the majority of powerboats I see never have the VHF turned on or may not even have one installed at all.
 
Today this very big ferry went past me about a 1/4 mile. Came from behind. He probably did not see me since I do not have AIS. :D Missed me by that much. Yes I knew where he was and we both held course.
 
Experience would have told you that.

Sorry no sailboat experience here. Hope I'm still allowed to participate.
But seriously though, the experience relevant to this thread is AIS experience and that I have. When I seek input about a piece of equipment from others, I am asking those that have and/or operate such equipment to share their experience. I would think that the OP here was seeking the same and it would be nice if we just offer real world experience as opposed to imagined ones from someone that doesn't even use such equipment.
 
Curious, have you ever owned a sailboat? I said I was shocked a sailboater answered a hail on 16. Why, because the skipper and crew are in the cockpit with wind whistleing through their ears and seldom have a VHF in the cockpit let alone a AIS display in the sunshine. Sailboaters usually do not have it turned on as they cannot hear it from below at the nav station.
Experience would have told you that.

When we chartered a sailboat in the BVI, I was shocked to find that the nav equipment was ALL down below, at a "Nav Station" instead of where it belongs, handy to the skipper, in the cockpit. At that stage in my sailing experience, I hadn't been on very many other sailors' boats, so didn't recognize that as a frequent thing. On my own sailboat at the time, I had no "nav station" below so everything was either permanently out in the cockpit or mounted on swing arms so that I could see and use the tools while minding the helm.

More recently, when chartering a sailboat in the Med, I again encountered the total lack of Nav tools in the cockpit, as all of it was below.
 
Pros - it's a useful tool that does add a bit of safety when in busy shipping/traffic areas.
Cons - none unless you are trying to hide.

Agreed... I can't think of any other cons for anyone other than trying to hide fishing spots or such... Not just for "busy shipping/traffic areas"....
 
Just an input here, been a sailor since 1976. Always having situational awareness and always had VHF in the cockpit as well as below. Now I have a motorboat tug. And let me tell you all, I feel more prone at the below helm, find myself running around the boat checking all quarters at all times. So any help I can get is great. AIS Radar VHF Select calling, and a better pair of binoculars too.


OK back on subject..... New m2000 GPS and separate VHF antenna for the system arrived ready to install.



So tech wise, installing another VHF antenna in for me a small boat creates problems, Needs to be more than 4 feet from any other VHF antenna. Need to get my tape measure out. Or utilize my small mast.
 
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