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    Re: The Sun does not stop for anyone
    From: John D. Howard
    Date: 2016 Dec 24, 09:08 -0800

     David,

    Azimuths are plotted on plane paper ( charts ) all the time.  A universial plotting sheet the cel navagators use to plot is plane - NOT Mecador.

    You plot the azimuth from your position ( AP, DR, MPP, GPS, etc. ) and the azimuth is valid.

    Agreed, you  could not sail for hundreds of miles on a heading derived from a plane chart but that is not what you are doing.  You are plotting a bearing from where you are standing to the sun just like any bering.  Because the intercept is short - up to 30 NM - the angles the azimuth cross all the meridians is the same to a tiny amount.

    If you are plotting from a fixed position on land there is no reason to even draw meridians other than the center one - the one you are on.

    After all the LOPs are plotted you measure the delta Lat. by whatever NM scale you were using and the delta Lon. by distance from your position horzonatily th the fix then multiply by the cosine of your Latitude.

    Many people think the plotting sheets are Mecator but they are not.

    John H.

       
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