Location, location, location
currently in: Charleston, SC

A quick update while we still have WiFi. First of all, I've set blog comments to forward to the radio email, so we'll get them now no matter what. (That is, comments on the windom.netrack.net site; if you're reading this via an aggregator or the LiveJournal syndicated feed, I can't get those comments.)

Second, I'm going to try to be conscientious about position reporting when I check in on the radio email. This means that you can go to http://www.findu.com/cgi-bin/winlink.cgi?KG4EYP and retrieve a nifty little map with our (more-or-less) current position.

And speaking of position: the big project we did while here in Charleston was installation of a new VHF antenna for our new AIS receiver. AIS - Automatic Identification System - is a VHF broadcast that all big commercial ships are required to make, giving their name, destination, location, course, speed, and other information. Our new navigation software plots this information, so we bought a box - basically, a special-purpose VHF radio that receives on the AIS frequencies and converts the data into NMEA - and today we hooked it up. (That makes it sound easy. Actually, it took all day to pull the cable for the antenna, install the cable ends which were actually designed for a different gauge cable, reposition our existing equipment to make room for the new box, and so on... And it took all day yesterday to navigate the bus system to get out to the mall to find a Radio Shack to buy the various cables and ends and bits, of course, so the total time expended is entirely out of proportion to the result!)

But finally we got everything installed and turned on the software, and hee, if navigation was like a video game before, now it's even more so. Here's a screenshot of the view from Charleston Harbor, with various ships coming and going; we can click on any of them and get full data: speed, length and breadth and draft, even cargo.

It's a fun little toy, but also, we figure it's a safety feature. We use radar when we're out in the shipping lanes, to help us stay out of the paths of big ships, but sometimes the motion of our boat makes it hard to tell whether we're on a collision course with a ship. Any more information to help us stay out of their way is useful. Plus, the radar (and our eyeballs) can't see around corners, but AIS does - the screenshot, for example, shows lots of ships on the other side of the peninsula of Charleston.

Not that we're going to be using it much for the next few days. We've finished our chores here and are ready to leave, but the wind is going to be light and from the southwest - right where we're going. So there's no point in going outside; we'll stay in the ICW for a while, where the only big ships we'll have to dodge are tugs with barges. (Hmm, if they are broadcasting on AIS, it might be kind of nice to see them before they come around bends!)


- posted by S/V Windom @ 3/22/2007 [link]