U A I S
Universal Automatic
Identification System
BC AIS Test 2000
First Result
On Wednesday July 26 SEA
PRINCESS was moored at the Franklyn Dock in Juneau, Alaska
when VOLENDAM came into Juneau. Following are some of the
better pictures taken by Edwin Mayer of GA International
Electronics of this 'Inter-Ship AIS Event'. The pictures were
taken from the screen of the STN Atlas ChartPilot with a
radar overlay.
1 
2 
3 
4
.JPG)
4 AIS
Window .JPG)
4 ARPA
Window
5 
6
The AIS target of VOLENDAM showed about 11 NM before the ARPA target appeared. At VOLENDAM's 17.6 knots that is a 40 minute difference with SEA PRINCESS at the dock. If SEA PRINCESS had been underway on a opposite course also at 17.6 Knots then there would have been a 20 minute difference. This means that, in this particular case, SEA PRINCESS' OOW would have been alerted of the presence of VOLENDAM 20 minutes earlier through AIS than though radar.
Pictures 4 and 5 show why target consolidation or target ranking is desired. The diamond shape is the AIS target and the circle is the ARPA target.
Replay of REGAL PRINCESS ECDIS
showing both VOLENDAM and SEA PRINCESS
The list at the bottom shows
the range to VOLENDAM (0245968000) and to SEA PRINCESS
(0233684000)
Replay of REGAL PRINCESS ECDIS
showing two targets for SEA PRINCESS
0233684000 is the AIS target
and B5 is the ARPA target