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    Re: Why are NA sight reduction tables not
    From: Gary LaPook
    Date: 2012 Apr 8, 11:36 -0700
    Are you sure that is the correct formula for finding Azimuth?

    The standard formula is
    sin A=(cos DEC sin LHA)/cos h.

    gl

    --- On Sun, 4/8/12, Alexandre E Eremenko <eremenko@math.purdue.edu> wrote:

    From: Alexandre E Eremenko <eremenko@math.purdue.edu>
    Subject: [NavList] Re: Why are NA sight reduction tables not
    To: NavList@fer3.com
    Date: Sunday, April 8, 2012, 10:05 AM


    Geoffrey,
    Thanks.

    The formula for the asimuth in NA seems a little
    more complicated than the one
    taught by PE. I don't know what is the reason for this more complicated
    formula.
    All Russian books use even simpler formula:
    sin A=(cos Lat sin LHA)/cos h.
    where A is the asimuth, h is the altitude.
    That's what I use.
    It requires 3 inputs of angles to the calculator (without memory) while PS
    requires 5
    and NA requires 6.

    There are also modified Russian formulas optimized for the calculator with
    one memory cell (like Casio f250), however I do not use them, because
    they compute asimuth first and altitude second, while I need
    only altitude in most cases for land observations.

    Alex.

    On Sun, 8 Apr 2012, Geoffrey Kolbe wrote:

    >
    > At 16:08 08/04/2012, you wrote:
    >
    >> I would like to follow this discusion,
    >> But what is the formula (for the calculator) taught by the Power Squadron?
    >> Can anyone give me a link with this formula?
    >
    > <http://www.akronpowersquadron.com/NauticalTools/SightReduction/SightReduction.shtml>http://www.akronpowersquadron.com/NauticalTools/SightReduction/SightReduction.shtml
    >
    >
    >> (I know two formulas for sight reduction).
    >
    > Why Alex, there is a world of excitement waiting for you then. ;-)
    >
    > Geoffrey
    >
    >
    >
    >
    >
    > View and reply to this message: http://fer3.com/arc/m2.aspx?i=118813
    >
    >
    >



       
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