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    Re: Thoughts on Celestial.
    From: David Fleming
    Date: 2012 Oct 27, 18:07 -0700

    Thanks to Chief Franklin for bringing to my attention the possibility that the fix has the possibility of being outside the cocked hat. I'm not sure if I ever knew of the outside triangle fix possibility or just forgot.

    That stimulated the thoughts illustrated in the attached file. Shown are the two cases.

    For azimuths > 180 , toward ( or away) points in or out of the triangle on each LoP. And we find the error common to each measurement by bisecting the angles and get the fix at the centroid of the triangle.

    For azimuths < 180 , toward ( or away) points on one of the sides in the opposite direction as the other two sides. The fix is found on that side of the triangle found in a way similar to the first case by bisecting the external angles producing a fix at the intersection of the bisectors.

    This procedure works for common equal errors such as index error or anomalous refraction. Besides getting the fix we also measure the error which would allow us to measure anomalous refraction or dip if we leave that factor out of the sight reduction.

    Dave Fleming
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