Atlas Cover

EDITORIAL
AIS messages are still as high as 30%, VTS Centres with accurate records indicate that the incidence of AIS errors of navigational
significance that are not immediately corrected is probably nearer 1% or less.
Clearly any level of error is unacceptable if AIS is used as the sole source of information and for this reason AIS needs to be
validated in the port environment if it is to be used for the provision of a navigational assistance service, or in the organisation of
traffic where it involves the management of navigational safety. There are many reasons why a VTS Centre would not consider
decommissioning existing radars and placing reliance for coverage solely on AIS at this early stage. However, AIS may allow a VTS
to extend its area of influence and there are examples of AIS being introduced for non-SOLAS vessels in the inland and river
environment where radar coverage may be impractical.
The messaging features of AIS are not widely used at present but early examples include the transmission of tidal data and security
related information. As users become more familiar with the system and its capabilities, it is likely that AIS messaging will be
used more widely for the dissemination of routine information that must otherwise be passed by voice over VHF.
In sum, the use of AIS ashore has provided a quantum enhancement of VTS capability. Whilst it may extend the horizon and the
ability to monitor traffic at extended ranges or in confined areas, AIS should be seen as another sensor. Properly correlated, AIS
provides the maritime world with the sort of additional track data, and more, that the air world has enjoyed for decades.
Barry Goldman
IHMA reprepresentative at IALA
and VTS Manager, PLA
Examples with radar video overlaid with AIS
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