Swingship, and getting a compass right
Nova Marine recently brought out a compass deviation and correction program called Swingship. Even the free download version could help you at least document just how out of whack, or accurate, your steering compass really is. If you care. It’s interesting how differently even very experienced boaters think on this subject. “The magnetic compass is the primary navigation instrument on any vessel,” writes the developer of Swingship, who I’ve heard is a solo trans ocean sailor. But the salty gent who took me out on his big Eastbay doesn’t much care that his beautifully mounted compass is off. Jeff Kauffman—a compass adjuster for 17 years, a serious delivery skipper even longer—told me this morning, “It’s a bitter pill for guys like me, but there is no question that the magnetic compass has become the secondary heading device on most boats.” I didn’t get to tag along with Jeff on that adjustment job last week, but today I got an interesting blow by blow description. I’ll write up the story soon. In the meantime, I’m deep into compass study. Sorry to report that while the online version of Bowditch (American Practical Navigator) still has a useful chapter on compass technology, gone is the detailed one on compass error that I see in my 1984 print edition. Also took another look at Alan Gurney’s Compass, a history I read last spring. What a fine book.
