T&T: AIS

[Dave Cooper]

G'day Hans, the "A" AIS is the one required for ships over 300 tons and any
international passenger carrying ship.

Alls B's are for unregulated boats.

All "A" are transponders. $3000 and up

All "B" are transponders. $1200 and up but this price may come down once the
units are FCC approved in the US and the volume of units increases. They are
currently CE approved and sold in the EU.

One can purchase receivers that receive both class "B" and class "B"
signals. $150 and up for single channel receivers. $400 and up for dual
channels receivers.

Few currently installed Class "A" transponders receive the full data stream
from a Class "B" transponder. This will slowly change as the software of the
class A units is updated BUT there is no requirement for any operator of a
class A unit to do so. A huge oversight, IMHO. In addition there is no
universal authority to report ships with non working or malfunctioning units
to. Another huge hole in the implementation and enforcement of AIS, IMHO.

We have 2 AIS receivers and one Class B AIS transponder. One of the AIS
receivers we used to check our own AIS signal which would otherwise require
another AIS ship to do so. We also can insure that we are transmitting all
the data that we should even tho the receiving ship may not be able to
receive it do to the lack of software upgrades.

We try to inform them of this but to date we have gotten very poor if any
response to them being told that their AIS unit need an upgrade. As there is
not potential to report them to anyone who can enforce them to do so we
remain without our name and some other data not being displayed. All seem to
get the MMSI number and our speed and heading. The rest may or may not be
interpreted by their software.

I have been in contact with Ben Ellison, he is "Panbo", and have tried to
come up with a database of who's class A transponders receive what messages.
With the ships stonewalling my obtaining this info as they either don't know
the status of the software revision or just don't wish to deal with isn't
know. However it seems impossible to do this from my side.

So we are grateful that we have it and it serves a very useful purpose.
However its isn't the panacea that it could be if all of the required ships
had it working and had the correct software installed.

Hope this helps a bit

As always YMMV....

Dave & Nancy
Swan Song
Roughwater 58