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Old 17-05-2013, 07:57   #136
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Re: Please turn your AIS off when docked/moored/anchored

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Originally Posted by nigel1 View Post
As far as I am aware, AIS is not interrogated, it just transmits, and any receiver in range will pick up the data.
Like the OP, i would prefer it if boats with Class B, tied up at the dock would turn the transmit function off when safely at the dock. Coming into a busy harbour, if I start to get a lot of alarms from Class B, I'll just filter the lot out if it gets to distracting. The hope is, we remember to remove the filter when back at sea. So from a big boat perspective, I'd appreciate it if Class B users would turn the transmit off when safe to do so
Thanks Nigel, Good to hear a big ship perspective. The interrogation I was thinking of was from a shore based station like a VTS, as a kind of "polling" I am not sure how much of it is done, if at all in practise? the report I referenced to mentioned it but the use seemed unnecessary, so maybe it's not a factor.

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Old 17-05-2013, 08:09   #137
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Re: Please turn your AIS off when docked/moored/anchored

I find Evans' argument about the commons an interesting one, certainly applicable to more than AIS usage for cruisers. I also find it interesting that the forum member most vociferously in opposition to Evans' suggestions has told us, outside of this thread, that he is not a boat owner, belonging to a sailing club where the owners can use multiple boats for a fee. How likely is it that those boats are equipped with AIS?

The fairway where I usually keep my boat has notoriously poor visibility at the entrance, especially at low tide. Many large power boats in the 70-90' range are slipholders, and almost all are equipped with AIS. It's useful to know whether any of those boats are moving in the fairway prior to getting close, because there's not room for two large boats to navigate the entrance simultaneously. At the same time, when outside the entrance one is navigating the busy Sausalito channel, which on weekends becomes so busy that radar is useless, even when attuned to the closest range. A navigator does not always have the leisure to study the chartplotter for more than a quick glance.

The fairway is a commons, and if neighbors are transmitting in their slips they make it more difficult to transit that commons on a busy afternoon. This compromises everyone's safety. But there's a simple solution, as Evans has suggested: turn the freaking things off while in your slip.

Cruisers Forum is also a commons, of sort. There aren't many places where one can get free advice from people with the amount of experience of an Evans Starzinger. But the barking dogs with an adolescent need listen to themselves growling in the dark make this commons less useful for all involved. Let's hope they don't chase master boaters away.

It's a simple request: stop fouling the commons.
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Old 17-05-2013, 08:19   #138
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Re: Please turn your AIS off when docked/moored/anchored

Evans, in general I don't see any reason to have AIS active while docked. I can see specific reasons like just taking on fuel or picking up passengers or waiting to be assigned a slip or working on a problem with the nav systems or doing some chartplotter planning or even getting a quick bite to eat, where turning the system off and on would be somewhat onerous.

Many of those boats might be getting ready to head out or have just returned in, where having the systems powered up may last an hour or so as the boat is put away or taken out. In a place like Newport, there are probably many valid reasons why a boat at a dock or mooring has their AIS on, as well as many non-valid reasons.

If there were 10 valid reasons within those 50 signals, would that have made your problem easier? I don't see how. When you docked, did you switch your AIS off the very moment you entered the marina?

However, that is not the problem and I do NOT see this as a "clean wake" issue equivalent to throwing trash into the ocean. I think you have gone off the edge there.

I don't think you will find anyone here who disagrees about throwing plastic trash in the ocean, as well as many other clear-cut issues like it. But the amount of disagreement with your characterizations in this case must show you that your opinion on this is just that, and not immutable, or even well-shared.

I am too thick-skinned to be offended by your description of people like me as selfish, immoral and not leaving a clean wake, but I am disappointed in your continued refusal to understand how your rants have labeled us as such.

I won't debate your ability to use your equipment, but I will again tell you that we would not have the problem you had. Perhaps your specific unit does not have the ability to adjust the filters, but that is not the problem of people who leave their AIS on.

I do not see why a CPA/TCPA filter would not have solved your active docked AIS problem. And this isn't something you have to constantly adjust - set it once and leave it on - you won't be needing it differently at sea.

The only way I can understand that you had a problem was if you were navigating immediately adjacent to the docks in the throughways. In this case, YOUR AIS alarms should have been turned off completely and eyeballs would have seen everything. A coal boat moving slow in a channel and needing AIS on a small maneuverable boat to evaluate and avoid the situation? Drunk power boaters do this daily there with no electronics at all.

And again, we would have had no problem with seeing and understanding that situation using AIS. But we do not have your unit, and we understand how to set the alarms and filters on ours.

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Old 17-05-2013, 08:28   #139
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Re: Please turn your AIS off when docked/moored/anchored

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Originally Posted by colemj View Post

I won't debate your ability to use your equipment, but I will again tell you that we would not have the problem you had. Perhaps your specific unit does not have the ability to adjust the filters, but that is not the problem of people who leave their AIS on.

I do not see why a CPA/TCPA filter would not have solved your active docked AIS problem. And this isn't something you have to constantly adjust - set it once and leave it on - you won't be needing it differently at sea.
Please tell me specifically in detail how you would have set the CPA/TCPA to avoid the problem? In a way that was not completely custom for this one situation and that I could just 'set and leave'.

I was navigating in a channel that runs past Newport harbor. The channel takes several turns, including legs where my bow swings over (pointing toward) Newport Harbor and all the boats in it.

As I said I know perfectly well how to, and in fact did, filter out alarms for all these targets, but in the process also filtered out alarms for the two 'real' targets.
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Old 17-05-2013, 08:28   #140
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Re: Please turn your AIS off when docked/moored/anchored

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Originally Posted by Bash View Post
I also find it interesting that the forum member most vociferously in opposition to Evans' suggestions has told us, outside of this thread, that he is not a boat owner, belonging to a sailing club where the owners can use multiple boats for a fee. How likely is it that those boats are equipped with AIS?
Interesting cherry-pick and characterization. You forgot about many others of us that disagree with Evans who do have boats, have lots of experience and are actively cruising.

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Cruisers Forum is also a commons, of sort. There aren't many places where one can get free advice from people with the amount of experience of an Evans Starzinger. But the barking dogs with an adolescent need listen to themselves growling in the dark make this commons less useful for all involved. Let's hope they don't chase master boaters away.

It's a simple request: stop fouling the commons.
A bit star-struck are we? Just because some disagree with a "famous" person (and you), we are adolescent dogs? Even when we provide valid and factual arguments without ad hominem attacks or broad characterizations? Unlike your posts on this subject?

The master boaters are still here, they just disagree with Evans on this single point. And some agree with him, but you already broadly painted anyone who agrees as a "master boater".

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Old 17-05-2013, 08:40   #141
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Re: Please turn your AIS off when docked/moored/anchored

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Originally Posted by estarzinger View Post
Please tell me specifically in detail how you would have set the CPA/TCPA to avoid the problem? In a way that was not completely custom for this one situation and that I could just 'set and leave'.

I was navigating in a channel that runs past Newport harbor. The channel takes several turns, including legs where my bow swings over (pointing toward) Newport Harbor and all the boats in it.

As I said I know perfectly well how to, and in fact did, filter out alarms for all these targets, but in the process also filtered out alarms for the two 'real' targets.
Lets say they are set so that alarms are shown for only those boats who will be within 300ft of you within 5 minutes. In a harbor situation, you would have to be very close to the docks, and heading straight for them, for this alarm to activate. In a channel containing a non or slow moving boat, this would provide plenty of time to understand and avoid any situation. Unless you are traveling at high speed and do not have any visibility at all. Then that is a different problem. And I would turn off audible alarms completely.

I leave these filters on at sea simply because I see every AIS signal from 20 miles away and can watch and track the vessels with miles of sea room and time to make course adjustments. Frankly, I don't find alarms useful at sea at all and turn them off (the chartplotter continues to color the ships based on CPA and movement).

Again, if you can agree there may be valid reasons for being at a dock with AIS active (I listed some possible ones you can peruse), would only 10 validly active, but docked, AIS targets have made your situation better?

And did you immediately switch off your AIS upon entering the marina, mooring field or anchorage you ended up in?

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Old 17-05-2013, 09:05   #142
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Re: Please turn your AIS off when docked/moored/anchored

I am in two minds as to whether OP (and others) are simply trolling. For their sake and for others I hope so.

Quote:
Originally Posted by Bash View Post
The fairway where I usually keep my boat has notoriously poor visibility at the entrance, especially at low tide. Many large power boats in the 70-90' range are slipholders, and almost all are equipped with AIS. It's useful to know whether any of those boats are moving in the fairway prior to getting close, because there's not room for two large boats to navigate the entrance simultaneously.
So you simply keep your fingers crossed that one of the others does not appear? - and if it does you DIE! or do you proceed on the basis that a vessel with no AIS might appear and then deal with it in the way you did before fitting AIS?

What we are talking about here is not a safety issue. It is at best demanding others inconveniance themselves for own conveniance (I am leaving aside that even a retard can understand that approach is doomed to fail , even if it were an actual safety issue), and at worst is a scary sign that the future of navigation / pilotage has arrived, and it ain't pleasant ....and that is a safety issue.

As said before, the work around for those who have a problem with too much AIS info (but still need it to do whatever it is they are doing) is to get on the VHF and let folks know that they are manouvering with difficulty and that they need a wide berth. Flying a flag or 2 for that as well might help avoiding sh#tting on the common. Hell, could even request a pilot . Or simply avoid confusing places.....seemples .


Quote:
Cruisers Forum is also a commons, of sort. There aren't many places where one can get free advice from people with the amount of experience of an Evans Starzinger. But the barking dogs with an adolescent need listen to themselves growling in the dark make this commons less useful for all involved. Let's hope they don't chase master boaters away.
I saw mention earlier on in the thread that his amount of experiance with AIS is around 1 year, and seems to be struggling with both the buttons (I sympathise!) and also processing the amount of info. Not sure if that makes someone an expert. NFI what folks did before AIS , but if getting confused thenperhaps better off going back to whatever it was - for all, including own blood pressure .

Anyway, that my lot on this thead. Well, probably .


......and fair play if I have been trolled - although I think a bit naughty to do that on such a subject. But WTF!, most of your boats are a long way away from me . fortunately .
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Old 17-05-2013, 09:14   #143
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Re: Please turn your AIS off when docked/moored/anchored

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Originally Posted by rivonia View Post
...........

When safely in a Marina the AIS "MUST BE TURNED OFF!!! .
Is that a law or your opinion?

You don't have to answer, I know the answer. It was correctly pointed out on the first page of this thread that it is futile to try to control the behavior of others. You and some other folks are getting worked up over nothing because you can't force others to behave the way you think they should.
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Old 17-05-2013, 09:33   #144
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Re: Please turn your AIS off when docked/moored/anchored

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And did you immediately switch off your AIS upon entering the marina, mooring field or anchorage you ended up in?

Yes, I did/do, usually when I turn off the engine (I hate to waste amps), certainly within less than 5 minutes.

Lets say they are set so that alarms are shown for only those boats who will be within 300ft of you within 5 minutes.

First, setting aside my personal thoughts on this, and providing an 'expert's perspective' on filtering . . . . Vesper has obviously given this more thought than either you or I. They have four pre-set filter/operating systems, "anchored', 'Harbor', 'coastal', and 'offshore'. And I am going to just suggest they have selected the 'best practice' for each situation. In their 'harbor' filter they have the CPA alarm set to .2nm, which is 4 times your 300ft and TCPA to 15 minute, which is 3 times your 5 minutes, so at least 'the AIS experts' disagree with your suggested settings even for a 'harbor' setting. For coastal CPA is set to 1nm, and TCPA to 30 minutes. The 'anchor' setting simply turns all alarms off. So, I would suggest that the most expert group I know on this suggest the best practice is rather different than your recommendation.

As to my personal experience and opinion, I have found that ships like an absolutely minimum of 1/4nm and much prefer 1/2 nm. I know last summer that I was required to give a vessel 2000m clearance by the USCG (with machine guns pointed at me). I also know that when these ships are doing 15-20 kts as they are often doing, even in constrained channels like in the Chesapeake bay, that 5 minutes is not very much warning at all to have a vhf discussion and then take action (like turning 90 degrees and getting a 1/4nm out of a channel). I like 15 minute warning in winding channels like the Chesapeake bay. So, I personally do not see your suggestions as a useful or appropriate 'set and forget' filter. Yes, I can filter out these alarms, and in fact I ended up doing that, but I don't (and apparently neither does Vesper) see it as the best/safest use of the shared collision system.

I leave these filters on at sea simply because I see every AIS signal from 20 miles away and can watch and track the vessels with miles of sea room and time to make course adjustments. Frankly, I don't find alarms useful at sea at all and turn them off (the chartplotter continues to color the ships based on CPA and movement).

Well I do find alarms useful (obviously). The fact that you do not may explain why you are willing to put such a tight alarm filter on. So, you seem to be trying to impose on me your dislike for alarms.

Again, if you can agree there may be valid reasons for being at a dock with AIS active (I listed some possible ones you can peruse), would only 10 validly active, but docked, AIS targets have made your situation better?

As I said in a post above, if there are just a few signals I can individually mute them.

I can certainly agree that it is entirely appropriate for a vessel having its AIS transmitting if it either was just about to get underway or just having finished. If there had been only say 5 active AIS in Newport it would have caused no problem. But there were 50, and I honestly don't think any of those vessels were either just about to or just had finished being underway - I saw none get underway and I saw none of the signals disappear (As they would if just finishing and not having quite yet turned the system off). This was mid-morning on a weekday, and these were all class B, and all that I looked at (about perhaps a dozen) said they were pleasure vessels. I do not think they were getting fuel or picking up passengers or getting a bite to eat. It is slightly possible that one or two were having their AIS worked on by a tech (your final 'reason' for having a docked AIS on).

where turning the system off and on would be somewhat onerous.

Excuse me . . . pressing an 'on/off' button is 'onerous'? This is what I don't get. Why not turn the systems off? What's so hard or such a big deal about that? Why are some of you so resistant to doing that? With the system on you are definitely degrading the shared capability for the AIS collision avoidance. I don't think there is even any question about that. You are both adding AIS 'noise' to the limited number of signal slots (As in when I went by NYC) and clogging up the alarm systems (as in when I went by Newport). Your suggested filters are NOT as safe as Vesper's suggested filters. Do you really feel it is appropriate to degrade a community safety system because you feel it is 'onerous' to press the off button?

I still have not heard one good reason to not turn off these systems when docked or moored, or to go to silent mode when anchored . . . except I will give you the particular special case of when you are installing/testing/trouble shooting the system but honestly you have to admit that's likely going to be extremely few vessels (perhaps one?).

It still looks to me like for your own convenience you are willing to foul a public commons, when it would be very easy for you to choose not to.
............
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Old 17-05-2013, 10:04   #145
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Re: Please turn your AIS off when docked/moored/anchored

estarzinger,

I mean no disrespect but:

Some folks here have held you out to be the Jesus Christ of cruising. That may be so and you may have more experience, more miles, and more awards than anyone on this forum.

That's all fine and good, but you are pissing into the wind if you think your request or insistence that other boaters behave according to your wishes and expectations will be met. You have no authority to demand compliance and even if you did, it's unlikely that people would comply. You can come up with a hundred reasons why they should comply but it won't make a bit of difference. You can call them bad boaters or worse, it won't make a bit of difference.

People may have their personal reasons for behaving as they do or they may just not be thinking about it. In addition, I would be surprised if the membership of this forum was even 1% of the total number of boaters on the water so your message is not getting out.

It seems to me that at this point, you are just arguing with people for no good reason. Your demands to "show me why ...... " mean nothing. Nobody is obligated to show you anything.

It's just like boaters making wakes, playing loud music, running portable generators in an anchorage at night, etc. You (and I) don't like it but there's nothing we can do to stop it.

For your health and blood pressure - just drop it. Learn to live with it, it's not going to change.
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Old 17-05-2013, 10:20   #146
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Re: Please turn your AIS off when docked/moored/anchored

I guess I will bow to yours and Vespars vast expertise over mine in specific situations. Funny, I find that sometimes I can adjust my radar outside of the preset generalized functions and tunings and get better performance in specific situations. This also works for our battery chargers, our alternators, our solar controller and many other systems on board. Many times I leave them in these states or save them over the manufacturer's preset ones. Maybe I am delusional.

As to Vespar's harbor recommendations, if one needs 1200ft and 15min warning to avoid large harbor traffic (the jet skis and bowriders won't have AIS), then one is not watching well. But what do I know. We have only been using our AIS for 7 years, so probably haven't developed any best practices and tactic in these situations yet. Remind me, was this your first time in a harbor like Newport with your AIS unit?

I also never said I keep my transmitter active. We only have a receive unit, but I am understanding and tolerant of those transmitting in this situation in which you are not understanding or tolerant. Different thresholds and opinions to me - dirty rotten bastards to you.

Onerous in turning off the unit refers to black box integrated units, where it is onerous to turn it off when preparing the boat, fueling up, etc. You have a button on your unit, but do not seem to have wide knowledge of other types of units. And I would much rather be assured that someone is moving their boat around with their AIS active rather than inactive because they forgot to specifically restart that piece of electronics before getting underway.

I don't see how giving ships wide berths is any different whether you have alarms set or not. At 20 miles on passage, I am always aware of all AIS ships in my vicinity. We have a personal comfort level of 0.5 miles minimum and always change course to pass 1 mile or greater whenever reasonable. We NEVER ask a ship to change course for us unless they are overtaking us in a manner in which we have limited maneuverability. We always take it upon ourselves to keep out of large ship traffic.

Even in your example of the Chesapeake, I find audio alarms not useful. Instead, I simply keep track of traffic. In shipping channels, there really is no reasonable alarm setting that won't drive me crazy. And if we have the depth and clearance to sail outside shipping channels, we do so as a matter of principal.

In a winding channel, that alarm is going to be going on-off-on-off, etc as both boats make turns through the channel. I can't see where the alarm is useful at all in this situation.

To me, the only tolerable use of audio alarms is to set guard zones so that you are alerted the moment an AIS target appears within the range of the unit. This gives one the absolute maximum time to understand the target, but is useless in any situation other than open sea.

If you are relying solely on an AIS alarm to keep you informed of navigational situations, I have no advice for you (of course some here think it is presumptuous and an affront to offer you advice at all).

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Old 17-05-2013, 10:24   #147
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Re: Please turn your AIS off when docked/moored/anchored

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Learn to live with it, it's not going to change.
With respect back . . . norms of behavior do in fact change. It was not that long ago (say the '70's) that cruisers did drop trash in the oceans. That has changed (of course a few still do, but most now do not). The way these changes in normative behavior happen is one person at a time until there is a tipping point and then a new norm develops. This usually starts with a very few people yelling about a problem they see developing.

Back a few years ago when AIS were few it was no problem to 'pollute' the system with docked boats. It is now a problem and all I am asking is that my fellow seamen consider modifying their behavior. I have not 'demanded' anything. I said 'please' in the thread title. I just ask you to consider this and whether you personally are leaving a clean wake.

I really don't care what you think of me or my reputation or experience.. You will note that nowhere in any of MY posts have I suggested you should listen to me because I am well known. I have asked that you consider my argument and then you personally act as you think is best for the sailing community. If you personally think hitting the off button is too hard or too much work or too onerous so be it.

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Remind me, was this your first time in a harbor like Newport with your AIS unit?

No.

We only have a receive unit,

Ah

But I am understanding and tolerant of those transmitting in this situation in which you are not understanding or tolerant.

I understand perfectly well. I just (Strongly) believe that the behavior is obsolete and currently detrimental to the community.

Onerous in turning off the unit refers to black box integrated units, where it is onerous to turn it off

I presume that black box is on a circuit breaker, or could be, or could have a simple switch added to the power cord. Just flip it.

I don't see how giving ships wide berths is any different whether you have alarms set or not.

Yes, I know. You don't find much value in alarms. I do. Since you are being so understanding and reasonable, please understand I (and others) find value in alarms.

If you are relying solely on an AIS alarm to keep you informed of navigational situations, I have no advice for you (of course some here think it is presumptuous and an affront to offer you advice at all).

Now you are just being snide.

As I said to Jeti, one of the reasons I find alarms helpful is that I am usually in fact NOT looking at the ais screen. I am sailing the boat and looking around.

I come to this forum to learn. I honestly asked what your cpa and tcpa settings were in the hope of learning something useful. Unfortunately, I guess because you really don't use alarms, I don't think your settings are useful for me.
......
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Old 17-05-2013, 10:31   #148
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Re: Please turn your AIS off when docked/moored/anchored

"So, you seem to be trying to impose on me your dislike for alarms."

I missed this point. No, Evans, I am not trying to impose anything on you. I offered an option because you seem to be driven batty by alarms.

Interestingly, most of my debate has been around trying to get you to see that YOU are imposing YOUR dislikes on others rather than developing useful coping tactics to a situation that is not going to change and only getting worse for you. And getting you to understand that you have been a bit nasty about character assassination in the process.

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Old 17-05-2013, 10:41   #149
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Re: Please turn your AIS off when docked/moored/anchored

There seems to be conflicting information about whether large commercial shipping actually monitors Class B. Anyone have any more definitive info to share, or does it come down to individual ships? I know they are required to transmit Class A, but are they also required to monitor both A and B?

My own opinion may change as I gain more experience, but I have assumed that the primary purpose of AIS onboard a recreational vessel was to avoid collisions with large, fast-moving commercial shipping. To that end, I saw little reason for a transmitter and opted only for a high quality receiver which displays & has alarm functions on my helm-mounted chartplotter. Although also having a transmitter certainly wouldn't hurt, I figured that, as a small, slow-moving recreational vessel, it is really my job to make sure I stay out of their way! Whether large shipping routinely monitors Class B obviously weighs on the validity of my decision.

I have also found AIS highly effective when sailing into busy harbors, esp. in reduced visibility. Here again, the primary purpose of the system is collision avoidance, and other reasons previously noted seem secondary, albeit apparently useful to some (e.g., anchor watch, theft, convenience, etc.). Whether one has or correctly enables any particular system's filters, to the extent Class B AIS is transmitting from recreational vessels while tied to the dock, moored, or anchored, it obviously has the potential to denigrate the ability of a vessel underway to decipher actual collision threats. Perhaps there is some utility if one is anchored near a channel or other vulnerable locale, but that can be resolved with add'l anchor lights. In fact, all of the reasons thus far given for transmitting while not underway can be accomplished by other means which do not risk impairing the primary function of the system, i.e. collision avoidance.

For these reasons, I firmly agree with Evans, especially considering that presumably most of the docked boats who have left their transmitters on have done so for no good reason, i.e. the owners have simply forgotten to turn them off. Not sure about the plastic in the water analogy, but perhaps using Ch. 16 for non-hailng/non-emerg. purposes is closer to the point being made by the OP.

As always, I look forward to considering the opinions of more experienced sailors, and will maintain an open mind.
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Old 17-05-2013, 10:44   #150
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Re: Please turn your AIS off when docked/moored/anchored

Quote:
Originally Posted by colemj View Post

Interestingly, most of my debate has been around trying to get you to see that YOU are imposing YOUR dislikes on others rather than developing useful coping tactics to a situation that is not going to change and only getting worse for you.

I know perfectly well how to 'cope'. I do it every day. BUT I also think that the behavior I am coping with is no longer appropriate and that my fellow seamen should consider changing. Its a behavior that no-one so far has offered a good reason for and which hurts the community.

And getting you to understand that you have been a bit nasty about character assassination in the process.

Since you don't even have a transmitter I can not see how you feel that I have attacked your character?

For others with transmitters, I have simply asked that they consider switching them off when docked or moored. I have simply stated, what is obviously true/factual, that they are polluting a public commons if they leave them on when docked/moored. I brought it up because they may not have considered that before.
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