NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Compass Error Corection
From: John Huth
Date: 2010 Jul 2, 15:14 -0400
From: John Huth
Date: 2010 Jul 2, 15:14 -0400
Holding off on the editorializing - the "1-in-60" rule bit me when I was teaching a navigation class to kayakers. I had to derive the dang thing from scratch without preparation because someone asked me about it.
Another one which is off a bit, but I use a lot is "1 degree is 100 feet at one mile". The next, even less precise rule-of-thumb is "every light house is 100 feet tall" (only accurate to a factor of 2 or 3)
I like the history, but most of my actual navigational practice is in sea kayaking. I find it pretty handy.
The British Canoe Union has a certification called a "5-star" rating. In doing the test, the subject is asked to find an obscure rock or location on the water in the dead of night. You're only allowed a compass and a chart. This usually is done in a region with a fair amount of tidal current, just to make things interesting. That's truly a fun exercise.
Having said all that, I do like the historical discussion - part of it is the ingenuity that people had in solving strange navigational problems. In any case, online discussion lists are always subject to bouts of grumpiness. It's the nature of the beast.