Canadian Yachting December 2017 - 37

AIS Carriage Requirements
While AIS can be a huge aide to safety-day or night-
the USCG does not require all mariners to carry this
equipment. Here's a breakdown of the kind of vessels
that are required to carry properly installed USCG
type-approved AIS transponders in U.S. waters.
Raymarine AIS650 Transceiver and
Raymarine eS9 HybridTouch Display
Operating in the VHF maritime band, the Raymarine AIS
system enables the wireless exchange of navigation status
between vessels and shore-side traffic monitoring centres.
Commercial ships, ocean-going vessels and recreational boats
equipped with Raymarine AIS transmitters broadcast
AIS messages that include the vessel's name, course, speed
and current navigation status.
www.raymarine.com

NMEA 0183 (and sometimes NMEA 2000) data backbones,
making it easy to network the AIS device to a MFD.
A third type of Class B AIS is available that allows mariners
to listen to incoming AIS transmission but which does not
broadcast its own navigational information. These AIS
receivers are popular, but it's critical to remember that while
you can see other maritime traffic via these devices, this traffic
is blind to your position unless they see you on their radar or
with their eyeballs.
In all cases, the biggest difference between these AIS units
is their power, range, and reporting rates.
All AIS signals can be "heard" by nearby vessels and aircraft,
as well as shore-based facilities, such as the USCG's
Nationwide AIS (NAIS) base stations, allowing the USCG to
monitor maritime traffic and use AIS as a Vessel Traffic Service
tool. Since AIS uses line-of-sight VHF communications, range
is typically limited to 10-20 miles, with masthead antennas
delivering better performance than obstructed antennas; also,
shore-based repeater stations can substantially extend this
range. While an AIS unit's range is limited, it offers better propagation than radar, allowing AIS signals to 'peer around' lowslung islands and making this technology ideally suited for areas
such as The Thousand Islands or the Pacific North West.
While mariners commonly use AIS for collision avoidance,
the USCG also employs the technology to mark navigational
hazards by broadcasting synthetic Aids to Navigation (AtoNs),
which are transmitted by an NAIS station to augment an existing charted buoy or aid, and virtual AtoNs, which are AIS signals
only (i.e., no physical AtoNs) in areas that are difficult to mark
with physical AtoNs.
The buoys marking Michigan's Straits of Mackinac are a
prime example of synthetic AtoNs, while the approach to
San Francisco Bay is marked by virtual AtoNs.
The USCG is also looking at other ways of leveraging AIS, as
this technology has the unique ability (equipment depending) to
deliver updateable messages to a commercial ship's Electronic
Chart Display and Information System (ECDIS) or onto a recreational vessel's MFD. According to the USCG's "21st Century

Class A AIS:
* Commercial self-propelled vessels of 65 feet
or greater.
* Commercial towing vessels of 26 feet or greater and
over 600 horsepower.
* Self-powered vessels USCG certificated to carry
more than 150 passengers, or that move certain dangerous, flammable or combustible cargoes in bulk.
* Commercial motorized dredging vessels that work in
a way that's likely to interfere with the safe navigation of other commercial vessels.

Class B AIS:
* Commercial-fishing vessels and most passenger
vessels that operate outside a USCG Vessel Traffic
Service or Vessel Movement Reporting Area may
use a lower-cost, fully compatible AIS Class B in lieu
of Class A device.
While recreational boaters aren't legally required to
carry AIS, a recent change (dated March 2, 2015) to
the USCG's AIS requirements pertains to "any vessel
equipped with AIS", meaning that all recreational
boaters who elect to carry AIS must abide by some of
the USCG's new AIS operations requirements as to
how they use their AIS. See www.navcen.uscg.gov AIS
Frequently Asked Questions for more information.
Furuno FA170 AIS
The Furuno FA170 is a standalone Class A, IMO approved
universal AIS transponder
with a clear 4.3 inch colour
display. The FA170 outputs
AIS data to ECDIS, radar and
other navigational equipment for collision avoidance
support. It has sufficient
output ports for dual configuration of ECDIS and your
radar system. It has LAN
interface available for
efficient network integration
into your bridge system. There is also a Bridge Alert
Management (BAM) ready feature that meets the specific
requirements for alerts and interconnection with bridge
alert management as specified in IMO MSC.302 [87]. The
FA170 also receives AIS - SART signals for assisting in
streamlining search and rescue activities. It is designed to
support larger vessels and commercial craft.
www.furuno.com

www.canadianyachting.ca

http://www.raymarine.com http://www.navcen.uscg.gov http://www.furuno.com http://www.canadianyachting.ca

Table of Contents for the Digital Edition of Canadian Yachting December 2017