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    On the accuracy of sextant shots, and position found therefrom
    From: Alan S
    Date: 2012 Aug 24, 21:02 -0700


    I speak of straight forward, non electronic position finding, or should I say, verification of what a hand held GPS unit tells me re where Iam, might I offer the following.

    1. Using a Davis ArtificialHorizon, standing in the parking area of my apartment complex, my calculated position usually falls within 2 NM of GPS coordinates, this with an AM sun line and a PM sun line, plotted on a USPS CLS plotting sheet which covers 1 degree long x 1 degree lat.

    2, Standing on the beach at Emerald Isle, North Carolina, working against GPS coordinates, I can shoot AM and PM sun lines, sun and moon lines of position, or moon and Jupiter LOP's, sometimes a 3 body fix, a star, the moon and Jupiter or Venus, calculated fixes obtained usually falling inside 5 NM of GPS coordinates.

    I have no doubt that any number of you all might do better, but then I'm simply an interested amateur, of questionable skill. Otherwise, I've never been to sea in a real ship, and I tend to get sea sick in small sail boats, so I can only speak to or of such experience as I've actually had, which likely isn't much, one does the best one can with whatever they have at hand. In any case, I have no doubt whatever that most anyone who obtained "good" results on the beach, their results in "the real world of small boats" might end up looking a whole lot less impressive

    I keep hoping, though not seriously, that one of these days, even a not overly accurate 2 body fix, from what I've read, they are not the most accurate of fixes, or AM and PM sun line fix will coincide with GPS coordinates. Like I said, I keep hoping, but I'm not holding my breath waiting.

    For some reason or other, the whole business continues to hold my attention and interest, indicationg I suppoose that people really are strange creatures.
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