Wayne.B wrote in
news
It's difficult to envision a time when all navaids have AIS
transponders installed, don't think it will ever happen except for the
very biggest/most important. Look at how many unlighted navaids we
have now, which is very low tech/low expense by comparison.

Wrong concept. It matters not WHERE the AIS signal comes from, only that
it is in range of your receiver. To plot all the navaids and
obstructions for the entire area, say Charleston Harbor, only requires
ONE, centralized transmitter, high up on a tower for maximum range. That
shore transmitter broadcasts all the data for all the navaids and known
obstructions from a database kept up by the local authorities, in our
case USCG. Every time a bouy is moved, the database would be instantly
upgraded directly from the terminal on the bouy tender, say over Marisat
or a military link. The very next beacon transmission from the area
shore station, you'd see the bouy moved to its new location on your
boat's AIS transponder, not 4 months from now when a notice to mariners
was ground out by the bureaucrats.

The navaids and other "targets" do nothing and have no AIS equipment at
all.....


If you have a good quality color radar with all the bells and
whistles, it is not that difficult to get the information you need.
My Furuno for instance has the ability to overlay the chart and radar
image on top of each other, and keep it aligned with your heading.


Yes, you see "something" on your screen, a blip. On AIS you see:

Name: Vaky Junior
MMSI: 377203000 [VC]
IMO: 7532650
Callsign: J8B2518
Speed/Dir: 15.2 kts / 262° W
Status: Underway
Dest: Portbury
ETA: Aug01 10:30
Type: Cargo (70)
Details: Bulk Carrier
Size: 245m x 32m x 11.8m
Tonnage: 41300 gt
Built: Oct 1983
Received: 18:32:28 31 Jul 06

which I just copied/pasted from Liverpool AIS live as I type this. You
know WHO he is, WHAT he is, WHERE he's headed, WHEN he's going to get
their, WHAT his course and speed currently is, HIS radio call and MMSI
for DSC calling.....and, armed with 41,300 Gross Tons, you'll keep a
respectable distance not available on Mr Furuno's green blob. AIS data
also tells your plotter his exact lat/long not listed in this listing
from the webpage so it can VERY accurately plot his crash potential MARPA
on the radar is only guessing at, frequently making gross errors if your
boat's rolling around a lot and the target's going in and out.

Just no comparison.....

"Coast Guard Charleston, we have AIS transponder aboard and running.
Please relay this information to the helo and cutter headed our way."

Not only would they have your 406 EPIRB data from the overhead satcomms,
but they can look at their AIS (assuming they ever get the damned things
installed) and plot your exact position for intercept course to help you.

I think AIS is FAR more important to marine safety than GMDSS will ever
be.....operational as well as emergency....

The sooner the government gets a constellation of AIS SATELLITES in LEO
polar orbit, the better!....