T&T: AIS Class B status

[Rich Losch]

We've had a Furuno Class A AIS system aboard for the last year, cruising
Puget Sound, Southern Canada, and Columbia River.  Used alone or with
ARPA, it a great aid.

My experiences with AIS give me an indication as to why the regulatory
agencies are/have been reluctant to approve the Class B systems.

The first obstacle will be ECDIS clutter and perhaps saturation. 
Areas like
Seattle, Portland, and Vancouver BC have high traffic densities, and as
the AIS systems are usually left ON, transmitting 24/7, chart displays
and radars are cluttered with vessel symbols.  Add pleasure craft to
this and it your display screens will be a mess.  What do users 
experience in Europe?

The second is AIS and VTS areas:  If you are in a regulated Vessel
Traffic Area as in Puget Sound, or southern Canada with a transmitting
AIS system, the traffic cops will expect you to participate.  This
requires a professional radio watch and at least 2 VHF radios, as well
as familiarity with the lingo and local area knowledge.  Maintaining
this VTS radio watch can take the fun out of cruising.  Yachts cruise 
where they
desire, and that means sometimes crossing a lot of traffic lanes,
whereas VTS expects predictability.

I also see the majority of AIS-equipped vessels do not update their 
NavStatus, or
have incorrectly entered basic vessel data.  On the other hand, we've
been challenged by the VTS cops as to what we were, so apparently they
disregard the transmitted info as well.

We've just returned from a trip from Portland Oregon to the San Juan
Islands.  By getting deep into the service screens on my AIS Class A
unit, I'm able to change to "RX only mode", that is receive (Class C)
only.  We used the Class A mode offshore and RX mode in the river and
Washington VTS areas.  Seems a good solution for us.  It would be nice
if we could switch the transmit function on/off a bit easier.

Rich Losch
RIO LINDA  KK 48-37
Salpare Bay, OR