AIS Broadcasts

[tpbrady]

I was going over that latest USCG notices to mariners in District 17 (Alaska), and noticed a note about AIS broadcasts of USCG VHF radio outages limiting coverage in some areas. The note says you will see on properly equipped chartplotters a 40NM ring around VHF radio sites that have problems. This is the first I have heard of this. It is a good feature but also highlights the problems the USCG and NOAA have in maintaining their radio sites. I wish NOAA would do the same thing when weather radio broadcasts have a problem.

Tom

 

[High Wire]

A 40 nm ring will only be visible if you are zoomed out far enough to see it, no? Who keeps their chart plotter zoomed out that far? Not me unless making a big change to areas.

 

[tpbrady]

I don’t know how it will be rendered on the screen. It may show up as a curved line when you are zoomed in or not even appear until you zoom out. If the USCG can do that with an AIS broadcast they could do a lot of other things. I don’t know if a broadcast like that would be persistent on a screen once received or go away once you can no longer receive it when it goes lost target. If it goes away it’s about as useful as the radio site it says is off the air.

 

[twistedtree]

Very interesting. It sounds like there is a target type with variable diameter. I'll keep an eye out.