AIS Do I Need It?

[skipmac]

Originally Posted by a64pilot

So can you do the same thing with CG boat registration?

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Office of Science and Technology

[DotDun]

I leave my AIS transceiver in 'silent' mode the majority of the time. I sail mostly in the daytime, outside of heavy traffic areas. I run 'silent' not because I'm worried about gov't tracking, I despise sites like MarineTraffic/Shipfinder/Vesselfinder making money off my information. MT has zero intrinsic value to the act/art of vessel collision avoidance. This plus the fact that a miscreant anywhere on the Internet can see my vessel out on the water is enough for me to run 'silent'. Low visibility or high traffic areas, I'm transmitting.

FWIW, if I could only have one, radar would be my choice. I like to see all vessels and all objects, not just those transmitting AIS.

AIS is valuable, but certainly not the panacea of collision avoidance as some describe it.

[JPA Cate]

As El Pinguino stated in the second or third post, the answer to the question of whether you NEED AIS, depends a lot on where you are sailing.

Where Dockhead sails, I completely agree with him that one should have it, and probably having the transponder is the better idea, as long as the ships' AISes can handle the volume of traffic. Ultimately, I think they have to have a higher priority for avoiding each other than piddly little sailboats that won't damage them a bit. In the English Channel, if we can agree to take as correct what Dockhead has written, the ships do a d--n fine job of avoiding us.

I still think that not everyone needs an AIS. I personally think I preferred having just the receiver, as mentioned above. So far. To be honest, I think I am in an adjustment phase with it. I do not like ours' placement, it's too bright. Might be okay in highly lit areas, but on the open ocean, its dimmest setting is too bright for my vision. I'd rather have to go below to check it. And it is a tool, I shouldn't have said toy. Some people use them like toys.

On the East Coast of Australia, there are lots of boats with AIS transponders. They leave them turned on while tied up in the marina and they've gone home. They leave them on at anchor. In my opinion, that is execrable use of the tool.

It was an interesting experience watching the little Marine Patrol (Australian Customs) jet come straight up our AIS bearing to him, right up our wake, then swing to the side to read off our name before contact. I can certainly understand how some people are fearful of leading the baddies to themselves. I am not sure whether this is unfounded fear, at this time, or if it varies where you are, world wide. We can turn the bloody thing off, and we can also use it, turn it off, then change course.

I like it for the fishing boats that have them, it does make them easier to avoid, but you don't need to be able to transmit to receive them.

And as to radar, some of us sail where the fishing boats are made of wood, some of them, and they do not make good radar targets, and nor do sailboats made of fiberglass and having no radar reflector. Eventually you get really close and they'll show as a target. Radar's great for following squalls, and for keeping off reefs with a break.

Ann

[Jon Eisberg]

Originally Posted by Dockhead

The point is that it is not the slightest overstatement. In open water you must use at least a hand bearing compass, in order to detect a risk of collision in time to do anything about it - in cases where difference in speed is double or triple or more.

If you do not understand how this works, and do it, then you are 100% dependent on two things - luck, and the ship's ability to see and avoid you. These two things maybe work most of the time, but what if he's taking a leak below, or is distracted, or just doesn't seem you?

Well, perhaps I've just had an extraordinary run of amazingly good luck, in all those years of sailing prior to the advent of AIS, and running boats without radar, or often even without so much as having a hand bearing compass on board… ;-)

I must say, I'm more than a bit baffled by the notion that it's so difficult to assess the risk of collision in open water, relying on the naked eye alone… And, if anything, the significant speed differential so often at play between sailing yachts and merchant vessels makes doing so even easier, at least for me… And I think most any kid who grew up racing dinghies - where the ability to judge angles and speeds on the water is one of the very first skills one develops - would likely agree…

Relative to this point, it's ironic that although AIS might give you a CPA to an accuracy within a few meters, or a TCPA to within seconds, one of the most critical bits of information is not provided by many units/installations… Namely, whether you will cross AHEAD of, or ASTERN of, the target in question…. Of course, that can easily be determined by making a momentary course change, but still… The skipper still may have to do a bit of thinking for himself, from time to time… :-)

Which leads to one of the potential downsides to this amazing tool, in the hands of some less experienced who may be lulled by its remarkable accuracy, and seeming 'infallibility'… 2 situations come to mind, where I was witness to boaters who might have been 'emboldened' by their faith in AIS, in their dealing with a crossing situation with a merchant vessel, restricted in their ability to maneuver…

One involved a powerboat and a tug on the Chesapeake, another a sailing vessel crossing the Charleston Harbor approach as a 800-foot container ship was inbound… In each case, the 'Pro' called the 'Amateur' as things kept getting closer, asking what their intentions were. Each time, the reply was to the effect of "Well, my AIS shows a CPA of at least a half-mile (or whatever), so T think I'll just hold my course, and cross ahead of you…" And in each case, the reply was a rather stern "Uhhh, CAPTAIN, I'd rather you didn't do that…" ;-)

So, in much the same manner we so often see 'GPS/Plotter-Assisted Groundings" and "Radar-Assisted Collisions", it's not hard to imagine similar occurrences as a result of blind trust being applied to AIS, as well…

As for me, being the Old School Wimp that I am, whenever I determine - sometimes with no more than a casual use of the naked eye, no less - I might be dealing with a collision course situation, I'll generally default to my trusty "I Think I'll Take His Stern" Mode…

It's worked fairly well for me, so far… Then again, perhaps I've just been Lucky...

;-)

[Paul Elliott]

Originally Posted by Ann T. Cate

I like it for the fishing boats that have them, it does make them easier to avoid, but you don't need to be able to transmit to receive them.

True, but I figure that if I like it when other boats transmit, then these other boats might very well appreciate it when I transmit. It's kind similar to a radar reflector in that regard -- if nobody was running (and monitoring) their radar, then our reflectors would be useless.

Anyway, that's why I have a transponder. I don't leave it on when I am tied up.

[smj]

Maybe to much time is spent looking at the screens of these expensive devices rather than looking at your surroundings and using common sense.
We helped deliver our old boat down the coast in the ICW years ago. The new owner had the chart plotter, radar and the ipad plotter app all going at the same time. I asked why, and he said he wanted to stay in the middle of the channel. He constantly drifted to the side of the channel as he wasn't looking at his surroundings just the electronic screens. I finally gave up telling him he was getting close to the sides as it appeared he didn't appreciate my concern. Long story short, he ended up running the boat up on the rocky shoreline as he was playing with his Ipad.
All electronics can be helpful as a tool to aid in navigation and safety, but in my opinion nothing can take the place of a good lookout and sometimes the time spent using those electronics takes away from time spent using your best tool, your eyes and your common sense.


Sent from my iPad using Cruisers Sailing Forum

[Kenomac]

Originally Posted by smj

Maybe to much time is spent looking at the screens of these expensive devices rather than looking at your surroundings and using common sense.
We helped deliver our old boat down the coast in the ICW years ago. The new owner had the chart plotter, radar and the ipad plotter app all going at the same time. I asked why, and he said he wanted to stay in the middle of the channel. He constantly drifted to the side of the channel as he wasn't looking at his surroundings just the electronic screens. I finally gave up telling him he was getting close to the sides as it appeared he didn't appreciate my concern. Long story short, he ended up running the boat up on the rocky shoreline as he was playing with his Ipad.
All electronics can be helpful as a tool to aid in navigation and safety, but in my opinion nothing can take the place of a good lookout and sometimes the time spent using those electronics takes away from time spent using your best tool, your eyes and your common sense.


Sent from my iPad using Cruisers Sailing Forum

Just like some knit whit fooling with a cell phone while crossing the street without first looking for cars. Good post!

[Dockhead]

Originally Posted by smj

Maybe to much time is spent looking at the screens of these expensive devices rather than looking at your surroundings and using common sense.
We helped deliver our old boat down the coast in the ICW years ago. The new owner had the chart plotter, radar and the ipad plotter app all going at the same time. I asked why, and he said he wanted to stay in the middle of the channel. He constantly drifted to the side of the channel as he wasn't looking at his surroundings just the electronic screens. I finally gave up telling him he was getting close to the sides as it appeared he didn't appreciate my concern. Long story short, he ended up running the boat up on the rocky shoreline as he was playing with his Ipad.
All electronics can be helpful as a tool to aid in navigation and safety, but in my opinion nothing can take the place of a good lookout and sometimes the time spent using those electronics takes away from time spent using your best tool, your eyes and your common sense.


Sent from my iPad using Cruisers Sailing Forum

Indeed. Common sense always and eyes usually, but for some things you need more - knowledge and skill. Eyes and common sense won't get you safely through a fog bank, and they won't get you out of a collision in open water, either - for that you need knowledge and skill, and at least a hand bearing compass.

Sent from my D6633 using Cruisers Sailing Forum mobile app

[JPA Cate]

Indeed. Common sense always and eyes usually, but for some things you need more - knowledge and skill. Eyes and common sense won't get you safely through a fog bank, and they won't get you out of a collision in open water, either - for that you need knowledge and skill, and at least a hand bearing compass. -Dockhead

Yup. And that's one time radar helps a whole lot!

NN

[Kenomac]

Originally Posted by Dockhead

Indeed. Common sense always and eyes usually, but for some things you need more - knowledge and skill. Eyes and common sense won't get you safely through a fog bank, and they won't get you out of a collision in open water, either - for that you need knowledge and skill, and at least a hand bearing compass.p

I can't remember. DH, are you one of the folks we've met who've ditched their radar in favor of AIS? Or, do you still have and use radar.

BTW, the Pamster and I use radar, binoculars and our eyeballs for collision avoidance. The AIS receiver is only used to confirm what we already see.

[conachair]

Originally Posted by Kenomac

...... the folks we've met who've ditched their radar in favor of AIS?

People actually do that? That's nuts. Like getting rid of your socks when you buy a pair of gloves.

[El Pinguino]

Originally Posted by Dockhead

Indeed. Common sense always and eyes usually, but for some things you need more - knowledge and skill. Eyes and common sense won't get you safely through a fog bank, and they won't get you out of a collision in open water, either - for that you need knowledge and skill, and at least a hand bearing compass...

I can't remember when I last used a hand bearing compass to check if a ship was on a steady bearing when navigating, etc visually.... easy enough to do it without one.

[Kenomac]

Originally Posted by conachair

People actually do that? That's nuts. Like getting rid of your socks when you buy a pair of gloves.

Yes... Seems so, but we know several who've done just that. One couple who routinely sail at night on long passages, relying solely on AIS on a beautiful new 2 million dollar yacht.

[Dockhead]

Originally Posted by Kenomac

I can't remember. DH, are you one of the folks we've met who've ditched their radar in favor of AIS? Or, do you still have and use radar.

BTW, the Pamster and I use radar, binoculars and our eyeballs for collision avoidance. The AIS receiver is only used to confirm what we already see.

No, definitely not! I use radar, AIS, and the Mark I eyeball. Anyway radar and AIS don't have coextensive functions. You can't do any kind of navigation with AIS, for example. With rare exceptions -- I did navigate into a strange harbor at night -- with no paper chart -- and no electronic chart -- by dropping waypoints along the path of a boat ahead who was broadcasting AIS.

[Dockhead]

Originally Posted by El Pinguino

I can't remember when I last used a hand bearing compass to check if a ship was on a steady bearing when navigating, etc visually.... easy enough to do it without one.

Not at 5 to 8 miles out you can't. It's not easy even with a HBC. You can get the roughest approximation by using a stanchion as a transit, but the accuracy of that depends on a very steady heading.