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Subject: Sextant Accuracy
From: Fred Hebard (Fred@XXX.XXX)
Date: Sun Mar 16 2003 - 20:45:52 EST
The location of my house seems to be settling down to perhaps 0.3 to
0.4 nautical miles north of its actual location. All of this with an
artificial horizon. One new technique I tried was to preset the
sextant to the future altitude of a body and then watch the body pass
through that altitude while listening to the time being counted out.
My general objective is to get these observations as accurate as
possible, say to within 0.1 or 0.2 miles. I'm not sure why I have this
objective, but it persists.
Bill Murdoch mentioned he had never bothered to apply instrument
corrections to readings taken with his Freiberger, implying that it's
not necessary to achieve accuracies better than about 1 nautical mile.
That also seems to be the general opinion here, especially with regard
to observations from small yachts, where it often is not possible to
get more accurate. But how about larger vessels? Does anybody want to
defend trying to get accuracies closer than 1 mile?
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