16.11 Using AIS to avoid collisionsYou can use the AIS safe zone and safety messagefunctions to help you avoid collisions with othervessels and objects.Safe ZonesA safe zone is a ring centred on your vessel withinwhich a target is considered dangerous. It isdisplayed in the radar or chart applications as a redring.This AIS safe zone uses the same criteria as MARPAand will deem a target dangerous if it comes withina specified distance of your vessel (closest point ofapproach or CPA) within a specified time (time toclosest point of approach or TCPA). The CPA andTCPA are calculated using COG/SOG and positionfrom the AIS target.When your system recognizes a dangerous AIStarget:• The target symbol changes to red and flashes.• The dangerous alarm dialog is displayed (this canbe disabled if required).• The dangerous alarm sounds (this can be disabledif required).Note: When the AIS unit is connected andfunctioning, the system will check for dangeroustargets within the safe zone and if enabled issuean alarm whenever necessary. Dangerous targetalarm operates irrespective of the status of the AIStarget display, or the safe zone ring.Safety MessagesWhen the status of the AIS Safety Messagesfunction is set to On, any incoming safety messagesfrom surrounding vessels, shore stations and mobilestations are displayed in a dialog box. If known, themessage will include the sending vessel’s position inlatitude / longitude. You will have the option to:• Remove the message (Ok).• Place a waypoint on your chart / radar to mark thesending vessel’s position (Place Waypoint).• Goto the sending vessel’s position (GotoWaypoint).Note: You will NOT receive any safety messagesin Simulator mode (homescreen > Set-up >System Settings > Simulator).Showing the Safe Zone Ring in the ChartapplicationTo show the Safe Zone ring follow the instructionsbelow:From the Chart application:1. Select Menu.2. Select Presentation.3. Select Overlays.4. Select Safe Zone Ring so that Show is selected.Selecting Safe Zone Ring will switch the zonering between hidden to visible.Showing the Safe Zone Ring in the RadarapplicationTo show the Safe Zone ring follow the instructionsbelow:From the Radar application:1. Select Menu.2. Select Presentation.3. Select Safe Zone Ring so that Show is selected.Selecting Safe Zone Ring will switch the zonering between hidden to visible.Enabling and disabling AIS safety messagesin the Chart applicationFrom in the Chart application:1. Select Menu.2. Select AIS Options or *Radar & AIS Options.3. **Select Targets.4. Select AIS Set-up.5. Select Safety Messages.Selecting Safety Messages will switch betweensafety messages On and Off.Note:*When Radar overlay is also enabled the menuname becomes Radar & AIS Options.** Step 3 is only required when Radar overlay isenabled.Enabling and disabling AIS safety messagesin the radar applicationFrom in the radar application:1. Select Menu.2. Select Targets.3. Select AIS Set-up.4. Select Safety Messages.Selecting Safety Messages will switch betweensafety messages On and Off.Displaying safety-critical AIS informationFrom the chart or radar application:1. Select the AIS target.The AIS target context menu is displayed.2. Select AIS Data so that On is highlighted.Selecting AIS Data will switch between AIS dataOn and Off.The Safety critical AIS data will now be displayednext to the target in the application.192 gS Series
