If you followed the 35th America’s Cup (AC35), you’re well aware of the mind-numbing speeds that the boats “sailed” at, the dizzying closing speeds involved, and the electronic sensors and on-the-water umpires that issued real-time penalties to transgressing teams, as well as the constant stream of spectator craft on Bermuda’s Great Sound, where the racing unfurled. While the skippers and afterguard aboard the fast-flying catamarans clearly knew their way around the course, the same could not always be said of the spectator fleet, some of which sailed to the island nation to watch the on-the-water action. Yet despite the close quarters and the wide discrepancies regarding local knowledge amongst the spectator fleet, everything stayed safe and well-organized thanks to some clever implementation of technology.
The Automatic Information System, or AIS, was devised as a way to avoid vessel-to-vessel collisions using onboard transponders, GPS, VHF communications, receivers/transceivers, and vessel-specific, 16-digit Maritime Mobile Service Identity numbers (MMSI; essentially, a unique phone number for your vessel).
When networked with modern chartplotters that are running up-to-date digital cartography, AIS graphically indicates (and sometimes alarms) dangerous targets (i.e., vessels that are on collision or near-collision courses with your vessel) and allows you to contact the other vessel directly, via their MMSI number and your VHF, to resolve the situation.
While AIS has been a godsend to countless mariners, it can also be used to set up virtual or synthetic Aides to Navigation (for example, electronic signals that mark rocks in places that are inaccessible or inhospitable to physical AtoNs) or to shift whale-protection zones based on real-time activity reports, which are displayed on networked chartplotters just like any other AIS target (but with their own unique onscreen icons). Read the full story
Emirates Team New Zealand, Oracle Team USA, Ernesto Bertarelli’’s VAVA and cruise ships - Day 5 2017 35th America’’s Cup Bermuda