SailNet Community - View Single Post - Standard Horizon Matrix AIS+ GX2150
View Single Post
post #13 of Old 03-24-2013
Senior Member
TakeFive's Avatar
Join Date: Oct 2009
Location: Swarthmore, PA
Posts: 3,821
Thanks: 12
Thanked 101 Times in 90 Posts
Rep Power: 8
Re: Standard Horizon Matrix AIS+ GX2150

I think that if someone needs a new radio anyway (old radio is broken or lacks DSC capability), then spending an extra $50-100 for integrated AIS is worth it.

Don't be emboldened to go out in fog just because you have AIS. (I think the same should be said of radar.)

While it is true that AIS does not show most boats under 300 tons, it does show all boats above that size that are operating legally in US waters. If you are under sail, you are usually the stand-on vessel, except when other vessels are so large or unmaneuverable that you have to give way. (When in doubt, just give way and leave enough distance that there is no confusion over your intentions.)

My point in parphrasing this rudimentary navrule is that vessels that don't show up on AIS are more likely to be give-way vessels anyway. Nothing is 100% certain, and you always supplement AIS by standing watch, but the fact is that the AIS transmission requirements for >300 ton vessels gives you added warning of the vessels that you need to be most worried about.

In my own case, I sail on a busy river with lots of commercial traffic. There are always 4-5 large freighters or tankers on the horizon 2-3 miles away. From that distance, I cannot tell whether they are coming at me or not. But the AIS tells me whether they are. (The vast majority are anchored.) Knowing that they are anchored enables me to relax and sail. (But of course they could raise anchor and head down the river any time.)

Before anyone calls this an example of complacency, realize that "false alarms" can distract you from real hazards that exist. When I know that those 4 vessels on the horizon are anchored, I can focus my attention on other true hazards around me. So AIS increases my ability to concentrate on things that are actual hazards.

All of this is true only if you do not allow AIS to embolden you to take risks that you would otherwise avoid. But that's true of all safety equipment.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

2001 Catalina 34MkII Breakin' Away (at Rock Hall Landing Marina)
PO of 1998 Catalina 250WK Take Five (new owners relocated to Baltimore's Inner Harbor)
1991 17' Trophy (Lake Wallenpaupack)
1985 14' Phantom (Lake Wallenpaupack)

Last edited by TakeFive; 03-24-2013 at 09:42 AM.
TakeFive is offline  
Quote Share with Facebook
For the best viewing experience please update your browser to Google Chrome