Whenever we set out on our vessels, there are sure to be other craft out on the water moving along at cruising speed with their crew occasionally looking out for other vessels. As sailors, we implicitly place trust in our fellow boaters, assuming they’re looking out for us the same way we guard their safety by using best practices as mariners.
Having someone on watch 24/7 is obviously necessary, but this practice isn’t fool proof, particularly in inclement weather that includes heavy fog or rain. Imagine approaching the anchorage at Little Fisherman’s Cove, Catalina Island, and a mile outside Bird Rock, rain starts pouring down hard, reducing visibility to 100 feet.
You vaguely discern a dull, white light in the darkness, but you can’t tell if it’s a channel marker light or a mast light through the heavy rain. And even though the chartplotter clearly indicates your position and the location of the white light on Bird Rock, you can’t tell what else is lurking out on the water. If a channel marker is beckoning you, that’s great. But a collision with another vessel, or with the rocks on either side of the pass, could spell a life-threatening catastrophe.
Fortunately, with the latest generation of AIS transceivers, we have a means of knowing what is out there, even in those moments when the watch takes a nap. Of course, this assumes either the channel marker or phantom vessel off your bow is equipped with AIS, protecting the channel marker or other vessel from you as well.
To start off, the standard AIS-equipped VHF radio is limited to receiving AIS transmissions and displaying them on either a small screen or a separate chartplotter. To alert another vessel, the operator calls by VHF radio or activates the DSC (digital select calling) function, which transmits the vessel’s name and position with the vessel’s MMSI code.
So there is an obvious advantage to installing a self-contained AIS transceiver on your vessel: as long as the AIS is on, every vessel in your area equipped with an AIS-capable VHF radio is aware of your location. If two vessels with AIS transceivers are approaching within an unsafe distance, both crews are aware of the potential or collision and have time and sufficient distance to correct course. Particularly if you’re singlehanded and sitting at the helm steering through dense fog, you need to know your AIS transceiver has your back.
A number of AIS transceivers have emerged on the market to fill the needs of offshore sailors, particularly those of us whose vessels aren’t t equipped with radar. One example of a high-quality, permanently mounted AIS system is the SI-TEX SAS-600, a sophisticated, fully certified, 5-watt Class B AIS transceiver possessing “the same network capabilities as Commercial Class A AIS units.”
Though this model, with its impressive, 5.7-inch, full-color LCD display, is intended for commercial vessels, it’s also a great choice for cruising sailboats. With input voltage of 12-24 volts DC and power draw of less than 12 watts, a mid-size yacht with an 8D house battery and a healthy charging system should have no trouble keeping up with the SI-TEX’s amperage draw.
Full-color C-Map Max cartography is a key component of the sophisticated SI-TEX AIS system, which can serve as a back-up to your main chartplotter. A built-in GPS and GLONASS satellite navigation receiver help to keep you on track while staying in touch with other vessels in your area.
You may install the SI-TEX SAS-600 on a dedicated pedestal or flush-mount it to the nav pod in the cockpit. The unit is rated IPX6 and IPX7 waterproof. At roughly $1,500, this device is at the top of its class and the choice of many commercial vessels, as well as cruising craft.
The Em-Trak A100, “the world’s best-selling commercial grade Class A AIS,” measures 8.2 inches wide by 4.1 inches high by 5.4 inches deep. While not exactly diminutive, it’s still of appropriate size for a medium to larger sailing yacht.
The Em-Trak A100 transceiver features a grayscale display, NMEA 0183 communication, and a GPS antenna with 33 feet of cable. The A100’s plug-and-play connectivity permits easy networking with other electronics in your nav station.
Em-Trak’s rugged AIS transceiver is easy to install and use and has demonstrated a record of “proven reliability” on both commercial and pleasure craft. With a water resistance rating of IP52, the A100 is best installed below decks, although it can stand up to a good dose of dust and ocean spray. With a price tag of roughly $500, this model certainly offers a lot for such a modest investment.
Another high-quality, yet more affordable AIS model is the ICOM MA510TR AIS transponder with GPS antenna. This Class B device is capable of receiving both A and B AIS signals, which allows a broader range of detection and enhanced safety.
Featuring NMEA 2000, NMEA 0183 and USB connectivity, the ICOM MA510TR can talk to virtually any other electronic device on your vessel, such as a chartplotter, radar, VHF radio or external GPS.
With its IPX7 rating, this waterproof ICOM transponder can be installed in the cockpit alongside the GPS chartplotter and VHF radio for maximum safety while navigating through a crowded seaway. This unit also features a man-overboard (MOB) signal, a collision alarm and an anchor watch alarm, which is activated when the vessel is adrift at anchor. Available online for roughly $800, the ICOM MA510TR AIS offers top quality from a name we trust.
For sailors on smaller vessels, such as runabouts and kayaks, the ICOM M94D floating, handheld VHF with GPS and AIS can make the difference between disaster and arriving at your destination alive and well. The M94D packs 6 watts of transmission power, has a battery life of 10 hours and is rated IPX7 waterproof. However, it’s important to remember the AIS function is only a receiver — the electronics industry has yet to produce a handheld AIS transceiver. But given the fast pace of industry innovations, such a product will probably appear on the horizon in the near future.
A big part of safety in any seaway in today’s cruising environment is not only knowing where we are, but also knowing where each other are on the water. Installing a high-quality, stand-alone AIS transceiver is one big way of ensuring our safety in an ever-more crowded cruising aquasphere.
