Tuesday, July 16, 2024
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The A Thru Z of AIS

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The problem is I’m a coward. I scare easy. And when I’m scared (how do I put this delicately?) I pee my pants. Of course, I pretend I’ve spilled my coffee or drooled or nocturnally-emissed… but my wife knows better. And my wife does not find this erotic. Nor do I. In fact, I’ve had to install extra-large capacity bilge pumps on Wild Card just to handle ‘code yellow’ while sailing offshore.

Okay. I’m a wimp.

Plus, I’ve always had a fondness for initials. For example, my name is Fatty and so I always tell everyone my initials are O.B.C.T..! (Say it fast.) I know, I know… weird, eh? Perhaps this started when I was young and my whole family used to refer to me as an SOB. (Sailor On Board, I’ve always assumed.) Yes, that was SOP in my family, who were mostly WOPs on my mother’s side.

Where was I? Ah, yes. How I got my love of initials. This is common, isn’t it? I mean, doesn’t everyone love TLC (tender loving care), THC (tender hemp care) and LSD (Lovely Shimmering Dreams)?

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…don’t initials like this just make you LOL?  J!

AIS – Advancing Navigation Technology

But, getting back to marine-reality for a moment, one of my biggest fears, both inshore and offshore, is collision. This is because I’ve nearly collided with waterborne LUOs (large uncaring objects) a number of times in the Pacific, Indian and Atlantic oceans.

That’s also why (about 12 years ago) I purchased a then-sophisticated CARD system (collision avoidance radar detection) to avoid collisions. This worked, sort-of, but not always—sometimes large passing ships with radar whirling wouldn’t set it off. And this is also why I purchased a Furuno 1623 radar last year—in the misguided hopes that its ‘guard alarm’ would dependably alert us to approaching/encroaching vessels… which it does sometimes and doesn’t do other times… and I can’t seem to determine why, how or when enough to say its ‘guard alarm’ is actually dependable.

…all of which leads us back to AIS… which stands for Automatic Identification System which is now mandatory equipment on most large commercial vessels.

The original idea was brilliantly simple: we were all sailing around with GPS units and VHF radios… so why not combine the two for collision avoidance? So an international group (IMO, International Marine Organization) of nav NERDS (not exactly real dumb studs) got together, made some rules, spit out some specs… and ASAP… on the QT… AIS was born.

Now all large ships worldwide have a GPS hooked to a VHF transmitter which continuously broadcasts an AIS ‘packet’ of nav info about them: their lat/lon, speed & course, name, callsign, tonnage, destination, length & beam, etc.

All ships? Well, almost. All international ships over 300 tonnes, all domestic vessels of 500 tonnes and all passenger carrying vessel are required to carry AIS.

Basic Storms Tactics for Cruising Sailboats

How do I know all this? Because while in New Zealand I happened to bump into an American computer-geek guy named Jeff Robbins on a Nordic 40 named Vesper at Westhaven Marina in Auckland. We immediately hit it off—by that I mean he laughed at my jokes and was completely oblivious to my flirting with his lovely wife, the Divine Deirdre.

Now Jeff was a sailor but he was also a nerd. I mean, the slide-rule in his pocket-protector had its own PFD! That’s right—he subscribed to men’s magazines which had three-page fold-outs of naked Abacuses! And Jeff was smart: always muttering about culturally integrating his circuits, interfacing with facial recognition sites and various other cyber-wet-dreams.

…and, so, one day he announced he was going into the marine electronics business to… to… to manly-manufacture… well, he couldn’t quite explain what it was or what it did or who’d needed it… but, hey, when your head is that high into the cyber-clouds… you don’t have to make sense to make money!

Now, frankly, I’d forgotten all about Jeff in the last year or two, until I started to notice well-found cruising vessels in the Indian Ocean with AIS Watch Mates manufactured by Vesper Marine… you guessed it, Jeff and the Divine Deirdre were making a big splash in the Southern Hemi’s electro-world!

Needless to say, I had to have one, like, pronto!

I dashed to the internet and 72 hours later had a unit in my hot little hands.

Hooking it up was straight-forward: two wires from my Garmin 152 GPS to the tiny, hidden VHF receiver tucked under my nav station, a power cord, a four-foot high antenna on my aft deck, and a pre-wired plug to the display head.

Since it just ‘listens’ and doesn’t transmit, this AIS unit requires almost no juice… a tiny of a fraction of an amp.

I tested mine while recently rounding Singapore and heading north up the Malacca Straits—perhaps the heaviest traveled body of water in the world.
Within seconds of being turned on, the AIS started to acquire ‘real-time’ information about all the ships within VHF range of my 38 foot sloop Wild Card. Soon it had 128 of ‘em listed on its display.

Of course, 128 is a confusingly large number. So the Vesper Marine unit can prioritize the vessels in a number of interesting, programmable ways. For instance, it can ring an alarm when a vessel gets within a mile of yours… or, even if that vessel is still 20 miles away but is PROJECTED to pass within a mile of you… it will ring the alarm also.

DIY, Fatty Style

Jeff calls this the CPA, or the closest point of approach.

Anyway, all these inputs are endlessly variable so I was able to quickly set up and customize my unit to serve my own Fat needs. Even better, there’s a ‘pre-set’ bunch of custom-modes so that once you get everything as you like it—you can just click on ‘anchored’ or ‘coastal’ or ‘offshore’ and you’re all set.

All the alarms are instantly mutable—and the muting affects only the vessel which triggered the alarm.

My wife Carolyn liked the mute button so much she glared at me and said, “…if only you had one, Fatty!”

My primary reason for desiring an AIS was, of course, collision avoidance. However I now see a myriad number of safety features to owning one:

  1. At night, AIS tells you without fail that those scary, fast approaching range lights are, at present course and speed, going to pass exactly 1.4 miles to your south… which can be a huge relief when you’re stressed.
  2. Since I now know exactly the position of the vessels around me, I can deduce tons of nav-data from when and where they’re turning, etc.
  3. Bad weather doesn’t affect AIS like it does radar.
  4. It can ‘see’ around ships and headlands, again an improvement on radar.
  5. I can keep it on 24/7 (unlike radar) because its power needs are miniscule.
  6. While typical VHF distances are 20 miles or so, we’ve had contact with lofty ships in ideal conditions at 40 miles… think of the SAR benefit for both parties involved!

Personal Satellite Based Message and Location System

And the benefits of AIS are exploding in completely unplanned and wonderful ways. They are now being put on breakwalls, lighthouses and even sea buoys. Severe weather alarms are being sent on them. Ditto, safety and mayday messages.

AIS transponders can even be where they aren’t, so to speak: let’s say a vessel sinks in the channel. The local authorities will put a ‘virtual’ AIS buoy close-by ashore which all AIS equipped ships will see as a ‘sunken obstruction.’

The first day I used mine I discovered the ship off my starboard side was aground. I’d have assumed he was just stopped or at anchor without my AIS. (Yes, since my AIS gave me his MMSI number I could have called him direct and asked him which he’d misplaced: his chart or his reading glasses… but, being a kind, considerate & compassionate gentleman… I did not do so.)

Who knows what technical innovations a bright AIS future might bring? I certainly wish someone would make a waterproof, ultra compact unit for my life raft supplies.

I’m extremely miserly with my money and also very conservative with my shipboard electrical power—but I plan to someday have a Class B (small vessel or yacht) transponder aboard Wild Card which I can flick on after ‘seeing’ a large freighter approaching from 30+ miles away!

My only complaint is that the AIS unit was so intuitive and user-friendly that Jeff refused to send the Divine Deirdre along with it to… to master its knobs! Damn, it turns out Jeff is smarter than I thought!

Let’s Get Technical – Collision Avoidance with AIS

(Editor’s note: for more info, contact www.navcen.uscg.gov (US coast guard site on AIS) or go to (vespermarine.com).

Cap’n Fatty Goodlander lives aboard Wild Card with his wife Carolyn and cruises throughout the world.  He is the author of “Chasing the Horizon” by American Paradise Publishing, “Seadogs, Clowns and Gypsies” and “The Collected Fat.”  For more Fat-flashes, see fattygoodlander.com.

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Cap'n Fatty Goodlander
Cap'n Fatty Goodlanderhttp://fattygoodlander.com/
Cap’n Fatty Goodlander has lived aboard for 53 of his 60 years, and has circumnavigated twice. He is the author of Chasing the Horizon and numerous other marine books. His latest, Buy, Outfit, and Sail is out now. Visit: fattygoodlander.com

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