AIS Update

[Curtis]

I know a group buy was proposed a few months ago. Did many of y'all install the receivers? Prices continue to drop: Milltech Marine is advertising the SR161 for $189US.

They also have a VHF Splitter that allows you to use your existing VHF antenna as both an AIS Receiver and a standard VHF Transciever. It isolates the AIS when it detects transmit. Anyone have an educated opinion on such a device?

Curtis

[sded]

I bought the Milltech Marine AIS receiver for $169+$12 shipping through the group buy. It is excellent, and works just as advertised, with very good sensitivity. I tried it out from home (top of hill) and could actually see ships at 50nm. Mounted a separate antenna on the stern. Active splitters are expensive and not terribly reliable. Mounted on the rail, I see things on visual, radar, AIS at comparable distances, and need to keep a sharp lookout for small fast non-AIS things anyway. Splitter makes a nice "gee-whiz" out of AIS though.

[Kojakal]

There is also another splitter unit existing in Europe. This device is called easySPLIT and it has got one feature more, which is a separte output for the FM Radio.
http://www.easyais.com

[db8us]

In some countries if your has to have a DCS-Radio it might not be legal to use a splitter.
I just ordered the EASY-AIS and splitter :-)

[R2boat]

How long do you think it will be before the ICOM's and Standard's will have a VHF out that has AIS included as part of the package?

[delmarrey]

Originally Posted by R2boat

How long do you think it will be before the ICOM's and Standard's will have a VHF out that has AIS included as part of the package?

When a lot more people go offshore. Most never get out of sight of land...................._/)

[CSY Man]

I know a group buy was proposed a few months ago. Did many of y'all install the receivers?

Yeah, I installed a 161 from Milltech Marine.
Used a separate antenna on the stern rail.
So back there, just in front of the solar panels I have 1 VHF antenna for the AIS, one VHF antenna for the # 2 radio, another antenna for the Navtex and one for the GPS.
Makes this boat look like one of them Russian spy-trawlers that was always seen in the vicinity of any offshore NATO excersize: Lots of antennas to monitor every move.

Never seen a ships name or call sign on the AIS data field. Wonder if every ship captain has been sloppy and not programmed their AIS transmitter properly, OR if the problem is on my end?
I see all the other data fields however, the speed, course, closest point of contact, etc.

[Curtis]

Originally Posted by delmarrey

When a lot more people go offshore. Most never get out of sight of land...................._/)

To my way of thinking, this kind of thing will be very useful around port areas. I know I always get hyper vigilant when I'm sailing around the entrance to Tampa Bay because of the ship traffic. Would be nice to be able to get a big picture view of traffic in one place.....

Curtis

[Talbot]

Very usefulat entrances to ports where ferries pop out at speed (e.g Dover or Cherbourg), but it is even more useful when you are trying to cross a separation lane.

[btrayfors]

For AIS lovers, here's a dissenting voice.

AIS is GREAT: to give you details on commercial vessels in your vicinity which could, conceivably, be a hazard to your safe navigation. And, gee whiz, isn't it great to be able to identify that little blip on the radar and know which ship it is, which way it's headed and how fast, etc., etc.?

AIS is POTENTIALLY DANGEROUS: because it doesn't give a synoptic (complete) picture. It only tells you about commercial vessels with working AIS systems. But, what about all the yachts, big and small, the fishing boats, the barges, the fish traps, the lobster and crab pots, the floating obstructions, and all the other things which could make for a bad day if you fail to take account of them? Do you really want to stay mesmerized in front of a screen cataloging the statistics on a few commercial vessels which you can, in any case, readily see if you just glance around the horizon once in awhile?

No, thanks. I'm a techie, electronics nut, lifelong offshore sailor, computer professional, and all the other stuff you'd think would condition me to be a sucker for AIS. No, thank you. This is technology we just don't need for safe navigation of a small vessel.

I believe that a careful watch visually and on the radar is the way to avoid potential collisions, not being lulled into a sense of complacency by watching AIS targets overlaid on your radar or however. These merely take time away from what you really ought to be doing, i.e., scanning the horizon with your eyes and a good pair of binoculars.

Bottom line: Far too much information about far too few targets.

IMHO.

Bill

[Talbot]

AIS is POTENTIALLY DANGEROUS: because it doesn't give a synoptic (complete) picture.

If you continue that argument, you would also get rid of the radar as well, cause that provides spurious images, and others are hidden by clutter.

No it is another aid (and very useful too) - I dont even need to look at mine to be aware that there is a potential problem. The system (shipplotter) has an audible alert which will provide an appropriate warning of any ship that will potentially enter a warning area (customisable) within a designated time. This alert system overrides everything else on the laptop, so if you are doing planning or just navigating, the alert will draw your attention to the potential. Believe me when you are negotiating a very busy shipping lane with seperation zones and a constant stream of fast (and some very fast) moving traffic, this warning is a great boon. It enables you to make that miniscule adjustment early that stops a close quarters situation.

It also helps to resolve a radar plot. But it is an aid and needs to be used as an aid (just like radar)

[Sandero]

Bill makes a great point about AIS. Only some vessels support it so don't expect to see them all.. especially the ones who don't have it.

Having said that... if you DON'T rely on any ONE navigation tool, but use as many as you can... you ARE better equipped to navigate. Where I am sailing now... 1 out of 5,000 boats may be equipped with AIS and that may be too high of a pecentage.

I have and AIS receiver, but at this point it is a cool "gimmick".. but the idea is rather awesome... if they can get it sorted out.

Jef
sv Shiva
Contest 36s

[btrayfors]

Talbot and Jef both make good points apropos of my "slander" of AIS.

If I were to regularly be sailing in, e.g., the English Channel or the Straits of Malacca -- the most heavily congested waterways in the world with large ship traffic -- then AIS might make some sense. But, only if I had the discipline to use it as just one additional tool (as I do radar), rather than get immersed in the data it provides. I'd be worried, though, about its entertainment value -- so many fascinating details about ships all 'round me -- and its subtle seduction, making it all to easy to believe that it really had a handle on all the ships and yachts and whatever 'round me.

But I don't regularly sail in the English Channel or in the Straits of Malacca, so for me nothing beats looking around the horizon with a good pair of binoculars with a built-in compass (Fujinon Polaris). If the bearing's not changin', you're in a potential collision situation and need to do something. A simple solution which works equally well with ships, yachts, floating logs, fishing boats, or whatever

Bill

[Sandero]

Bill,

AIS software not only fills the screen with data about ships, but computes potentional hazards and sounds alarms... guard zones etc... CPA and so on. Again you dont want to rely on the electrons... but it can assist you... and so it has its place in your bag of tricks.

But YES YES YES.. there is a mesmerizing effect of looking at screens of data... instead of standing watch.

Personally since my plotter is below, I tend not to do too much screen staring underway... and when I do pop down for a look see... I hustle back up because of my inherent paranoia that something I can't see in the nav station is showing itself from the cockpit.

I use a small IQue in the cockpit which has no nav functions and just gives me a little view of where the electrons think I am on their chart... and I refer to that to confirm what I see.

Radar I need to go below for a close look, but I can read it "a bit" from the cockpit.

When is someone going to offer electronic pressure transducers for your sails for trimming purposes? hahahaha.

Jef
sv Shiva
Contest 36s

[Jentine]

ships must be equiped with AIS, but may shut it off at the Masters discretion. I have not found a ship using it yet in Long Island Sound or New London, CT.