Automatic Identification System
Using AIS Equipment Can Improve Recreational Boating Safety
Position and safety data transmitted by commercial vessels is freely available to recreational boaters that purchase readily available AIS receivers
A new generation of technology stemming from increased global demands for improved ship security can also improve safety for recreational boaters. Changes mandated by the International Maritime Organization (IMO) and the Marine Transportation Safety Act in the United States require larger, commercial vessels to use Automatic Identification System (AIS) equipment while underway. Information broadcast by commercial AIS transponders is available to recreational boaters through the purchase of modestly priced receivers that can interface with digital chartplotters installed on many boats.
What Kind of Information Can AIS Provide? - A chartplotter display or a shipboard radar display overlaid with electric chart data can mark the positions of every noteworthy vessel within range of the AIS receiver. Each vessel displayed through AIS will have its speed, heading, name, radio call sign, Maritime Mobile Service Identity (MMSI) number, course over ground, rate of turn and much more information available with the click of a button. This represents a remarkable wealth of data previously available only to Coast Guard Vessel Traffic Service (VTS) operators.
What is an AIS Transponder? - AIS equipment is available as fully functional transponders and receive only units. Transponders transmit and receive in the VHF marine radio band. An AIS transponder is made up of several discrete components, a transmitter, two receivers, a digital selective calling (DSC) receiver, and a number of marine communication interlinks to allow data connections to other pieces of equipment. Using Self-Organizing Time Division Multiple Access (SOTDMA), AIS transponders can handle up to 4,500 reports a minute with other units and update the information displayed every two minutes. AIS equipment uses other equipment installed on the vessel to provide information like position, heading, and rate of turn.
AIS Receive Only Units - Recreational boaters can purchase a "black box" AIS receiver that can provide all the data freely transmitted by commercial vessels for display on existing equipment installed on their boats. It is more important for smaller vessels to receive AIS data than for their larger cousins to receive reports from small recreational boats. These units range in cost from $200 to $600. More expensive receivers can pick up both AIS transmissions simultaneously. In the near future, fully functional AIS transponders will be approved by the Federal Communication Commission that would be appropriate for use by recreational boaters.
The use of AIS receivers by recreational boaters will greatly improve safety. Boaters will be able to track the movements of large commercial vessels, avoid collisions in reduced visibility, and to hail other boats on the radio.
