Traditionally, navigational aids (also known as “aids to navigation”, or ATON) have been physical aids such as lighthouses, buoys, and beacons. However, AIS is one tool that has been used to provide mariners with “virtual ATON”, where no physical object or structure is associated with the navigational aid.
Using AIS, an authority can aid navigation by transmitting information where no physical ATON exists. AIS provides for the ability to send addressed messages to a specific wheelhouse (by addressing the message to the unique MMSID assigned to the AIS transponder on the vessel). AIS safety-related messages can also be broadcasted to all vessels within range of the broadcasting base station. While AIS-based virtual ATONs are somewhat “new territory” for mariners, there have been several applications within US waters. In the Northeast, AIS broadcasts have notified mariners regarding area whale migration activity. In Tampa, Florida, AIS was used to broadcast weather and sea state information to area mariners.
PortVision has been involved in a very exciting project in the Gulf of Mexico to use AIS as a virtual ATON to alert vessels who may be slowing or anchoring in pipeline areas. AIS addressed messages will be sent directly to the wheelhouse of vessels that may be at risk (or may pose a risk to fixed underwater assets). You can learn more about the pipeline monitoring project here.
Some of the benefits of an AIS-based virtual ATON are:
- Physical inventory of buoys and other monitoring devices to not have to be purchased, deployed, and maintained in the water
- An AIS base station can serve an extended geographical region – often in excess of 50 square miles per station
- Since the AIS base station is typically deployed in a fixed location on land (or on an offshore platform), acquisition and maintenance costs are typically lower than physical ATONs
Of course, there are disadvantages to virtual ATONs. The biggest drawback is that they require the mariner to have a minimum configuration of technical equipment in order to benefit from the ATON. For example, while an offshore supply vessel may be able to benefit from an addressed AIS message that warns them that they may be anchoring in a pipeline area, a recreational fishing vessel will likely not have the hardware or technology to receive such a broadcast.
At PortVision, we are very interested in working with industry safety organizations, pipeline operators, regional authorities, and the Coast Guard to design, configure, and deploy AIS-based virtual ATONs to increase safety on the waterway. If you would like to learn more about AIS vessel tracking, download our FREE info sheet below.
For more information about virtual aids to navigation, see IALA Recommendation O – 143, On Virtual Aids to Navigation, Edition 1, March 2010 [http://www.navcen.uscg.gov/pdf/AIS/IALA_O-143_Virtual_Aton.pdf ].