"Larry W4CSC" wrote about AIS / APRS:

Every boat should be on APRS on both HF and VHF through assigned VHF
and HF channels. Every packet APRS station can be a repeater for ever
other APRS station, far extending the range of the individual
stations. Some stations are connected through the internet to the
national APRS servers hams have setup, including www.findu.com. It's
all voluntary, of course, in true ham radio tradition.

For the marine application of APRS, visit Bob Bruninga, APRS'
inventor, at the Naval Academy website:
http://web.usna.navy.mil/~bruninga/aprs.html
He tracks the Academy's boat fleet with APRS on them. I fixed one of
the APRS stations on an Academy yacht when it was in Charleston a few
years ago to put it back online with APRS on VHF and HF. It keeps our
Midshipmen from being too lost...(c;

Larry, are you aware of any "findu" type charts that are adaptable to APRS?
Mapquest "maps" display a poor graphic when plotting a vehicle on long
bridges like the type that interlace the Hampton Roads Va area. It's not
that the position reported from GPS is inaccurate, but a graphic
representation becomes muddled when bodies of water are shown by Mapquest.
We're thinking the mapquest maps would accordingly be of little use in this
area as a result, but have not actually tried the equipment from a boat yet.

Jack
Va Beach Va