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iNav response to AIS MOB transmission - Printable Version

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- antipole - 09-05-2015

I am considering purchase of some AIS-based Personal Locator Beacons. In the event of going overboard, these devices transmit an AIS position and Message 14 (safety alert - either test or MoB).

Can anyone advise how iNavX responds to these? It will, presumably, plot the position of the target. But, ideally, it should highlight it other than as just another MMSI number and it should sound an alarm regardless of the setting of the AIS proximity setting and with a distinct sound.

I would also like to know how MacENC responds.

I copy below some information from the Digital Yacht site.

Tony

[color:green]There are two areas to check;

1) That your AIS Receiver or Transponder will receive and send the new Message 14 to your chart plotter, either via NMEA0183 or NMEA2000.

2) How your chart plotter/PC Software will react to an AIS SART situation i.e. does it sound an alarm and displays the AIS SART in a clear and distinct manner ?

When the AIS SART system was designed, compatibility with older equipment was achieved by using the existing AIS Message 1 – Class A Position Report. This ensured that all AIS compatible chart plotters would, at least, display an AIS SART as a Class A vessel. On these older chart plotters, no alarm would necessarily occur and the only way to tell if the target shown on the plotter is the AIS SART is to check if the MMSI number starts with 97 (reserved for AIS SARTs).

On more modern chart plotters (2011 or later), the new Message 14 Safety Related Broadcast is also decoded, triggering a Man Over Board type alarm and displaying the AIS SART on the chart with a special symbol, making it easy to identify and alerting everyone on board to the situation. However, many older systems do not react in this way and just show the AIS SART as another Class A vessel, with no special alarms or symbols.[/color]