NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: A basic sight reduction question
From: Gary LaPook
Date: 2012 Apr 4, 13:53 -0700
From: Gary LaPook
Date: 2012 Apr 4, 13:53 -0700
My Nautical Almanac has 276 pages of data and explanation and 30 pages of "increments and corrections." If you want perfect, good to the second, I&C tables then they will have to be 1800 pages long instead of the current 30 pages. All of life is an approximation and any concern you have about these corrections not being "exact" is lost in the noise of the rest of the celestial navigation process. A thorough study of thousands of sextant observations taken by professional navigators showed a standard deviation of about 1.5 minutes and if you are using H.O. 229 it states that the accuracy is usually within 0.2' with some weird cases producing errors up to 3.9' in the Hc so don't get too upset about the possible inaccuracy introduced by the I&C tables. Don't mention it too your students, they won't notice and why make it even more complicated for
them. 276 30 --- On Wed, 4/4/12, slk1000@aol.com <slk1000@aol.com> wrote:
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