Compass and Charts

[clearsea]

Originally Posted by s/v Moondancer

This rescue boat skipper lost his eye and he was criticised for relying on GPS as his only means of navigation.
Lookout! – issue 14, September 2009 - Maritime New Zealand

I have collected several of these stories and now consider this to be the most common navigation emergency in recreational boating: disorientation on a clear day close aboard shoal water while navigating by GPS moving map. This article reinforces my thinking about how to deal with that emergency: stop relative to the bottom (mindful of current and leeway and the fact that GPS does not provide a heading), get a non-GPS fix and plot it on a paper chart, and note the magnetic heading on a compass. Doing that in nasty conditions would be difficult indeed (night, windy, wavey, poor radar conditions). I'm still thinking about all the angles, and would be interested in other thoughts.

[osirissail]

Blaming GPS for spatial disorientation is like blaming cars for running into telephone poles. It is the driver/pilot who does not keep up with "where am I" that is the problem not the equipment. Local fishermen and other locals never have had any charts and know every inch of their waters. However, if you are visitor to "new" waters, it is "sooo" common sense to review maps (paper or electronic and guide books) before you get there and know what is where. Relying on a 2"x2" or even 3"x5" vector graph in a handheld or mounted GPS is equivalent to being near-sighted and not putting on your glasses. Just plain crazy.
- - However, your suggestion to stop and find out what is ahead is absolutely correct. Although it should be done a long time before you enter narrow or dangerous waters. All maps, paper or electronic are decades and more old when it comes to hydrographic and topographic information. The governments have money to update commercially used channels and buoys but nothing for the out-of-the way areas that small recreational boats go. That is where the cruising guides are worth their prices.
- - There is no shortage of naive sailors who believe $4,000 plotters must be absolutely "correct" just because they cost that much. Just look to land maps of streets and highways - they are also decades old. In a car you can pull over to the side and stop then figure out where you are. Not so in a vessel, the water is moving; the weather is changing; and other, maybe much larger, vessels are climbing up your stern. With rocks and reefs along the shoreline, there is no place to "pull over".