In the first part of our discussion about the Automatic Information System (AIS), we covered the nuts and bolts about how the system works, why its use has been mandated on certain commercial vessels, and, more importantly, how it can be useful to recreational boaters. Now we’ll cover the electronic gadgets and gizmos you can use to access all of that AIS information. And don’t worry, that doesn’t necessarily mean a large withdrawal of cash from your wallet, or causing your credit card to spontaneously ignite.
What all AIS devices have in common is that they display information from all nearby AIS-equipped vessels. Some of these displays are very detailed, like on a chartplotter, while some are small, even handheld. To work, AIS needs a GPS signal and a VHF antenna. But thanks to National Marine Electronics Association (NMEA) networking protocols, other electronics, such as a VHF radio, can be linked into your boat’s existing GPS electronics network to pull double-duty as an AIS transponder. For example, all that an AIS-equipped VHF radio needs is a networked GPS unit to plug into and a VHF antenna (which you need anyway) to broadcast the signal. There is similar functionality with other types of electronics such as chartplotters, GPS units, and handheld navigation units. All Automatic Identification System devices are rated in classes. Let’s check those out next.
Class A AIS transceivers are required on commercial vessels over 300 gross tons, and are generally very pricey. They transmit a plethora of information about the vessel every 10 seconds, including rate of turn, ETA to destination, International Maritime Organization (IMO) number, and much more. They also transmit at a hefty 20 watts, which means they consume good deal of power when operating.
Class B AIS transceiver units have a reduced function set and cost significantly less than their Class A brethren—they’re intended mainly for the recreational market. In addition to a reduced transmit rate (every 30 seconds), these units do not transmit vessel destination, ETA, rate of turn, draft, or IMO number.
Lastly, there are receive-only units. These units let you see what ships are around you, but don’t transmit any information about your vessel, keeping your location and any information about your boat anonymous.
One of the biggest advantages of AIS is that you don’t even have to buy a stand-alone unit to enjoy its benefits. Since an AIS transponder uses a VHF radio signal to broadcast ship information, land stations within range can intercept these broadcasts, and then display the information online via the Internet. That means if you have a cellular 3G or 4G connection, such as on a PC, smart phone, or tablet, you can access and display AIS information on these devices. Cool, huh? All you need to do with a PC is to log into a website such as www.marinetraffic.com, where you can access and view AIS information in your Internet browser. But I’m going to bet my lunch money that you have a smart phone or tablet that you bring onboard during your boating trips. That’s where apps come in.
Both Apple’s iOS and Google’s Android mobile operating systems support a wide variety of AIS apps to tap into, and most of them work equally well on smart phones and larger devices such as iPads or Android tablets that have cellular connections. Much like what you’d see in an Internet browser on a PC, these apps overlay ship icons and information onto a map, but generally come with additional features, such as providing track lines and the ability to search for specific vessels. One app, Boat Beacon, even allows you to use your phone or tablet to show your location on AIS maps. (You’ll need an actual boat, registration, and Marine Mobile Service Identity number to make it work.) One of my favorite AIS apps is MarineTraffic, which is available on both Apple’s App Store and from Google Play for Android devices. It comes from the same folks at www.marinetraffic.com, and overlays all sorts of great information in clear detail. Other apps that have good ratings and are worth a look include Ship Finder and Boat Watch.
There’s no doubt that AIS can add a significant relaxation factor to your boating activities, especially if you boat at night, or in conditions with reduced visibility—even if you only have a small fishing boat. The good news is that you probably already have a gadget to access the information in your pocket.