AIS Pros & Cons?

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I expect everyone actually does use their eyes.

Folks probably don't see something on an AIS screen, and then suddenly choose to ignore it from then on. Or suddenly forget it's there -- although I suspect forgetting is maybe more likely than intentionally dismissing.

For example, we don't use AIS to the exclusion of all (or any) other info sources. Including Mark I* eyeballs. And for the most part, I'd guess an AIS factoid -- benign boat on the display, flashing red boat on the display, audible alarm, whatever... is generally just an additional alert mechanism, over and above basic watch standing, radar alarms, depth alarms, etc.

I haven't seen anyone here say they love AIS and put their blinders on at the same time.

Although I don't have PSN's interaction history with seeming bozos! :)

Looks like only a few folks here seem to be saying they don't want no steenkin' additional watch-standing aid. Lots o' room for personal choice in that department...

-Chris

"Seemingly bozos"....just don't follow up with "birds of a feather flock together"........ :D
 
You said you did the math so I will take your post as accurate.
Suppose two boats are on a collison course and the collison is 340 feet from their reported positions. The collison occurred just as their last position is updated.
When does the collision alarm sound off?

I believe you can adjust the collision alarm to different distances.

So, the answer is up to the operator and the settings he/she made.
 
OK, like so many others, this thread has descended into name calling. :banghead:

Nothing more useful can come of it.
 
I believe you can adjust the collision alarm to different distances.

So, the answer is up to the operator and the settings he/she made.

The point I tried to make is being missed. No amount of alarm setting will make a difference if a boat does a crazy Ivan from the last known position/heading and is now on a head on collison course with you before your/their AIS sends out a new location for the alarm to react.

If only people here would not have called this a safety device. It is a tool and can be useful.
 
Only for those using AIS


Adding a PBL with AIS increases the chances of rescue in MOB situations IF you are boating in restricted visibility conditions, like night passages, dense fog, rough water conditions with waves hiding a person.

This in addition to EPIRB PBL.

A thought

Cost is minimal as compared to a loss of life.


Okay David, I'll bite. What the heck is a PBL?!?
Are you possibly meaning a PLB? (Personal Locator Beacon)?
 
I maintain that most of us pilot, rather than navigate. AIS is a nicety, but likely not a necessity.

If I was a river boater, I think it would be something that I would invest in.
 
I don't think anyone has discussed that the value of AIS depends on the type of boating you do. Do you have to go out in bad weather, at night, in tricky areas ? If yes, AIS is probably very valuable. If you have the luxury of not going out on bad days, avoiding high traffic areas and just being the average boater, it is probably less valuable.

Another discussion point that would have been useful is a ranking of electronics priority. If your boat didn't have AIS or an autopilot, which would you get first. How about RADAR vs AIS ....AIS vs Epirb. ( I am not suggesting these are competing devices, just trying to see which people think is more important ) Sure its easy to say "AIS is great. You should get it" but some people have a budget and may not be able to get all the gadgets they want right away. Sure it's only $600, but everyone here is fully aware of all the expected and unexpected expenses that come from just maintaining a boat, never mind trying to upgrade one.

As far as mandating AIS, I don't see that happening ever. Boaters are a small percent of the population, and cruisers are a small percentage of the boating world. There are probably 100 trailer launched bowriders for every 1 cruising trawler. For most of the boating world, I think "going boating" means you launch, go to the sandbar for a few hours and go home....or you go to the local restaurant with a dock.

In New England most people only boat between Memorial Day and Labor Day and only on weekends. That means there are really only about 30 potential boating days per year for the casual recreational boater. $600 for something that you are currently doing without and probably don't need, is a hard expense to justify for the average boater.

If anyone is still following this, I'd love to see what order you would install the following

VHF
Handheld VHF
Autopilot
Radar
Epirb
Night Vision
Stabilized Binoculars
Dingy w/ Motor
Crash pump
Air Conditioning.

Thanks
 
The point I tried to make is being missed. No amount of alarm setting will make a difference if a boat does a crazy Ivan from the last known position/heading and is now on a head on collison course with you before your/their AIS sends out a new location for the alarm to react.

If only people here would not have called this a safety device. It is a tool and can be useful.


I don't think I've seen anyone here not get your point?

FWIW, I look at all of our nav and watchstanding systems as safety-enhancing tools. Chartplotter (and charts of various construction) and depth sounder to avoid grounding, radar and AIS to avoid collision, VHF to ease meetings, etc.

None to be considered sole-source. None being magic bullets. None usually to take precedence over brain and Mark I* eyeball -- unless of course one of those has ceased to function. Haven't noticed anyone here saying they turn off their brains and close their eyes once they've installed X or Y or whatever system...

I don't seem to have much trouble considering a tool as being a safety-enhancing device.

Seems many folks here do that too. But apparently not all...

-Chris
 
Excellent question Benthic2. As you say the type of boating has a bearing on instrument choices. I think personal experience also has a bearing on the choices. For example I am very experienced using radar so place a higher priority on that than many recreational boaters. In retirement we are now fair weather, mostly daylight boaters from Wa State ranging north into BC and Ak. This area has different requirements as you move north, some heavily traveled by recreational and large commercial vessels, some places you hardly see another boat. Some areas very settled with help and support nearby, some remote where help and support could be a bit of a wait.

If I were outfitting from scratch:

#1 VHF, multiple. Good comms are too important to not have redundancy. Plus in areas with heavy commercial traffic I want to monitor multiple channels without scanning. 16, 13 and the appropriate VTS channel.

#2 Hand held VHF. For numerous reasons. As an additional VHF to meet my above requirement. For use in the dingy, both excursions and abandon ship.

#3 Dingy / motor. For excursions as well as abandon ship.

For my $$$ 1,2 and 3 are all required. I could lump all together and call them #1. I wouldn't venture beyond the San Juans without all 3.

#4 EPIRB. Still the best ‘yell for help’ device for a full on emergency.

#5 / #6 Radar / Autopilot. It’s a toss up here. At this point the costs are starting to pile up in my imaginary outfitting from scratch. Radar can do more that see through the fog. Collision avoidance, even without AIS, MARPA and the like. Simple old skool piloting by with range and bearing in any weather. Autopilot. It’s more than a convenience. It frees me up to pay more attention to what’s going on around me. If at this point in my outfitting I could afford just one then that choice would affect how I boat. For example without radar there would be a lot of days on the hook waiting for the fog to lift.

# 7 Crash pump, maybe. Good bilge pumps without doubt. I do pack a 110 Volt sump pump that with a generator and or inverter can be pressed into service should the bilge pumps not be able to keep up.

Not needed for the area / way we boat are
Night Vision
Stabilized binoculars
Air conditioning. We need heating more often.

Interesting that you don’t have a sounder, chart plotter + GPS or AIS on your list.

As a comment unrelated to your question. I prefer as much as real estate allows stand alone devices over MFD all in one devices. I want separate screens with separate functions, networking is OK but there are times I don't want overlays or small split screens. Plus if one goes down the others still work. I don't want devices that are touch screen only. When things get sporty or when my fingers are wet I want knobs and buttons.

I don't think anyone has discussed that the value of AIS depends on the type of boating you do. Do you have to go out in bad weather, at night, in tricky areas ? If yes, AIS is probably very valuable. If you have the luxury of not going out on bad days, avoiding high traffic areas and just being the average boater, it is probably less valuable.

Another discussion point that would have been useful is a ranking of electronics priority. If your boat didn't have AIS or an autopilot, which would you get first. How about RADAR vs AIS ....AIS vs Epirb. ( I am not suggesting these are competing devices, just trying to see which people think is more important ) Sure its easy to say "AIS is great. You should get it" but some people have a budget and may not be able to get all the gadgets they want right away. Sure it's only $600, but everyone here is fully aware of all the expected and unexpected expenses that come from just maintaining a boat, never mind trying to upgrade one.

As far as mandating AIS, I don't see that happening ever. Boaters are a small percent of the population, and cruisers are a small percentage of the boating world. There are probably 100 trailer launched bowriders for every 1 cruising trawler. For most of the boating world, I think "going boating" means you launch, go to the sandbar for a few hours and go home....or you go to the local restaurant with a dock.

In New England most people only boat between Memorial Day and Labor Day and only on weekends. That means there are really only about 30 potential boating days per year for the casual recreational boater. $600 for something that you are currently doing without and probably don't need, is a hard expense to justify for the average boater.

If anyone is still following this, I'd love to see what order you would install the following

VHF
Handheld VHF
Autopilot
Radar
Epirb
Night Vision
Stabilized Binoculars
Dingy w/ Motor
Crash pump
Air Conditioning.

Thanks
 
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If only people here would not have called this a safety device. It is a tool and can be useful.

AIS is as much a safety device as a VHF radio or a pair of binoculars. AIS can warn you of an approaching vessel before you can see it because of turns in the waterway or poor visibility.

It can also warn you that you are on a collision course with another vessel and allow you to change course well in advance of what you might do operating only visually.

AIS is a (safety) tool available to boaters who have installed it.
 
Thinking about it, AIS is a bit different from most other tools mentioned here. Having it makes your information visible to others, even if you aren't making use of the information it gives you. That's different to something like radar where it only gives you information, but having it or not doesn't impact what's available to anyone else.
 
If anyone is still following this, I'd love to see what order you would install the following

VHF
Handheld VHF
Autopilot
Radar
Epirb
Night Vision
Stabilized Binoculars
Dingy w/ Motor
Crash pump
Air Conditioning.


I think I'd put emergency comms up front:
- VHF, both fixed and handheld (actually have and prefer two fixed)

Then maybe I'd bundle nav-related tools, but in this order:
- depth finder
- charts (paper, MFDs/plotter, apps, whatever)
- autopilot
And restrict ourselves to daylight/mostly fair weather ops.

Eventually add a couple, in order, to lift that restriction:
- RADAR
- AIS

And I'd put EPIRBs, crash pumps, dinghy/liferaft into a separate category, somewhat more important than just "nice to have" but also taking some risk tolerance and risk management into account.

In my mind, some of the other options aren't so much about safe navigation (air conditioning) or fall into the "nice to have" category (stabilized binocs, night vision). Around here, not having aircon would be a big deal, but that's very likely more location-specific...

-Chris
 
I have been boating since before much of the modern stuff existed, and before I could afford it even if it did. As such, I equipped my boat (different boats, with different uses, over time) in the order presented below, but there are some other important safety-related things that took priority along the way, also as noted below.

1. VHF -- This was the first thing I added to my first boat, a 14' 35hp outboard in which I crossed the Catalina channel many times.

2. GPS -- Even navigating the Catalina channel, especially at night, can be a challenge to dead recon with sufficient accuracy, and on the mainland side it isn't easy to pick the right "light" to head to, especially since that first boat was so low to the water that most of the coastal lights were obscured by the horizon.

3. Epirb -- I have never had to use this, but bought one when they first became available. But, the nature of my boating activities (far off shore, at night), makes it more important than, for example, inshore daytime use.

4. Life Raft -- A life raft is safer than a dinghy, especially if the weather up. With a life raft, a dinghy is really just a convenience.

5. Radar -- When I first started boating, radars were huge pieces of power hungry and very expensive equipment that didn't include any MARPA functionality, so a life raft took priority. Today, it would precede a life raft.

6. Ditch Bag -- Not on your list, but I am combining here with a handheld inside.

7. Handheld VHF -- only in the ditch bag, see above.

8. AIS -- not on your list, but it sure helps with collision avoidance.

9. Night Vision -- Not a game changer like everything above, but then, at night, I don't venture into unknown harbors or even get anywhere near land, except at anchor. Still useful.

10. Stabilized Binoculars -- I have 3 sets, but use them exclusively for fishing.

11. Autopilot -- Even though APs are hugely convenient, I don't consider them to be an important safety item (though I could imagine circumstances . . .).

12. Air Conditioning -- purely for comfort.

13. Dinghy -- with a life raft on board, a dinghy is really just a convenience.

14. Crash Pump -- this is the one item I don't have, though I did consider it when spec'ing my boat. The builder talked me out of it suggesting 1) that if the boat is taking on a ton of water, my number one priority is to get a mayday off, set off the epirb, get the liferaft in the water and get everyone and the ditch bag on board, and 2), my boat's intakes for the mains are configured in such a way that a supply hose could be easily cut, at which point the main(s) serve as crash pumps.
 
2), my boat's intakes for the mains are configured in such a way that a supply hose could be easily cut, at which point the main(s) serve as crash pumps.

What output and at what RPM?

Our 24v bilge pump puts out far more water than the raw water pump ever could.

Raw water flow on our nta855m Cummins at cruise rpm is around 3 litres/minute
A single rule 3700 bilge pump puts out a theoretical 3700 GPH - 233 litres per minute

We have 4 of them in line at varying heights
Plus 2 X 240v trash pumps at the flick of a switch.
 
What output and at what RPM?

Our 24v bilge pump puts out far more water than the raw water pump ever could.

Raw water flow on our nta855m Cummins at cruise rpm is around 3 litres/minute
A single rule 3700 bilge pump puts out a theoretical 3700 GPH - 233 litres per minute

We have 4 of them in line at varying heights
Plus 2 X 240v trash pumps at the flick of a switch.

3 liters / minute sounds very low for an engine that size. My gassers will flow close to 40 gal/min at max RPM. It's a lot less at lower RPM, but even idling they're pulling something like 6 or 7 gal/min based on the time it takes to pull enough antifreeze through when winterizing. That's not still enough to replace a crash pump though.

I figure the Rule 3700 that's the highest pump in my engine room can move about 40 gal/min after accounting for installation losses.
 
3 liters / minute sounds very low for an engine that size.

This says 8 litres/m running full tits 1800 rpm - never been there
Another says 5 litres/m at 1500 rpm - very rare and only for minutes

1150rpm is our norm, 1250 if weather or current has a say in it.
Guessing that's going to be around 3 litres/m
 

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That's 8 liters per second, not per minute. It's showing 130 us gal/min, which is quite a lot of water.
 
That's 8 liters per second, not per minute. It's showing 130 us gal/min, which is quite a lot of water.

Yep, my mistake

But at cruising rpm, 3L/s = 180/minute
Still a long way off of a decent bilge pump
 
Yep, my mistake

But at cruising rpm, 3L/s = 180/minute
Still a long way off of a decent bilge pump

It's probably about what a Rule 3700 will do in installed condition. But I agree, it's not enough to substitute for a crash pump. Plus the challenge of operating it without potentially running the engine dry, especially if you also need the engine for propulsion. In most cases you'd be better off with other pumps or a big belt drive crash pump on the engine.
 
Wow that went a little off subject
 
I've used the engine intake as a crash pump (not on my boat.) I was pretty impressed by how much water the engine moved (Cummins 6cyl, forget the model.) Lots of commercial boats are set up this way.
 
Radio?? During my 15 years of sailboating in the San Francisco estuary (24- and 29-footers), we never had a radio. The only radio communications I've had on my motorboat was with other motorboats.
 
For people that don't have AIS and may be interested; I have included a radar overlay on my chart plotter from a few days ago that show two AIS targets to my left. A triangle with a pointer for their heading is shown. Their radar echo is underneath the AIS triangle. “Ocean APA" and “The Joker” were two recreational boats on my port side. A ferry "Cat Express" is to starboard.

A few years ago I was coming into this same harbor in pea soup fog and a CG Cutter hailed me by name and made some confirmations on our passing. At night or in fog, it’s an excellent tool.

Lastly, I am noticing more center console boats that head out far for fishing are installing them. A good thing, because they are hard to pick up on radar when its rolly polly.
 

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For people that don't have AIS and may be interested; I have included a radar overlay on my chart plotter from a few days ago that show two AIS targets to my left. A triangle with a pointer for their heading is shown. Their radar echo is underneath the AIS triangle. “Ocean APA" and “The Joker” were two recreational boats on my port side. A ferry "Cat Express" is to starboard.

A few years ago I was coming into this same harbor in pea soup fog and a CG Cutter hailed me by name and made some confirmations on our passing. At night or in fog, it’s an excellent tool.

Lastly, I am noticing more center console boats that head out far for fishing are installing them. A good thing, because they are hard to pick up on radar when its rolly polly.


That is awesome thanks
 
If anyone is still following this, I'd love to see what order you would install the following

VHF
Handheld VHF
Autopilot
Radar
Epirb
Night Vision
Stabilized Binoculars
Dingy w/ Motor
Crash pump
Air Conditioning.

Thanks


I won't have a boat bigger than a runabout without
VHF, Autopilot, and Dinghy



We go offshore a lot, so EPIRB, Handheld VHF, and Life Raft are essential


Radar and AIS are essential in New England and other places with fog.



In addition, the new boat will have Satellite Compass and a Bow Thruster



Air Con is nice to have
Stabilized binoculars are appealing, but I've never bought a pair.



We bought Night Vision before our circumnav. In the last 25 years since then, including the circumnav, we've used it maybe three or four times.



I teach Flood Control at the CCA's Offshore Hands On Safety at Sea Training. There are two kinds of floods -- those through existing holes and those coming through new holes.


The former can be stopped by using a tapered softwood plug -- you do have one of those attached to every through hull, with big ones for the shaft log(s) and rudder port(s), don't you?


The latter, caused by collision with land, a container, a log, or another boat, can be any size. Anything over a couple of inches is out of range for any reasonable crash pump. Find the hole fast and stuff a cushion in it or put a collision mat over it.


My best advice is to have a collision bulkhead at the bow and multiple bilges, so you cut down the length of bilge you have to search. That's a much better way to spend time and money than buying and installing a crash pump that will handle only a very limited range of problems.


Jim
 
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