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Re: Meridional Distances


Subject: Re: Meridional Distances
From: Dan Hogan (dhhogan1@XXX.XXX)
Date: Wed Sep 18 2002 - 12:28:49 EDT


For practical navigation I have been using Mercator Sailing and Meridional
Parts using the formula from The Calculator Afloat, by Shufeldt and Newcomer,
Naval Inst. Press, 1980, ISBN 0-87021-116-1.

        M = 7915.7045 x Log tan (45d x L/2) - 23.2689 sin L

        M = Meridional Part
        L = latitude

For the 90d/270d problem I have changed the TC +/- 1d depending on the
hemisphere. Couldn't use Rhumb Line because it wouldn't fit in my HP 35SII
and still have my other DR formulae.

Dan Hogan WA6PBY
C27 "Gacha"
dhhogan1@XXX.XXX
Nav-L Page: http://www.wa6pby.com





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