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    HO 211 variant
    From: Paul Hirose
    Date: 1999 Oct 03, 1:35 PM

    The traditional format for HO 211 sight reduction is cleverly laid
    out, but also uses quite a bit of space:
    
    t      156 54    A 40634
    d    S  56 44    B 26079    A  7773
    R                A 66713    B  1029    B  1029    A 66713
    K    S 121 07               A  6744
    L    S  53 30
    K-L     67 37                          B 41930
    hc      21 50                          A 42959    B  3233
    Z    W  13                                        A 63480
    
    I've developed a slight variation by shifting the last two columns to
    the left to use that empty space:
    
    t      156 54    A 40634
    d    S  56 44    B 26079    A  7773
    R                A 66713    B  1029
    K    S 121 07               A  6744
    L    S  53 30       1029
    K-L     67 37    B 41930      66713
    hc      21 50    A 42959    B  3233
    Z    W  13                  A 63480
    
    One column is all additions and the other all subtractions, as before.
    I don't mark 1029 as B, because that implies it's B of 53 30', which
    it is not.  It's just copied down from the R row.  Same for 66713.
    
    Advantage for this method is a more compact arrangement.  On a plain
    sheet of 8.5" wide paper I can work out meridian angle on the left, put
    the above items in the middle, and compute altitude corrections and
    intercept on the right.  It all fits without writing tiny.
    
    Obvious disadvantage is that you have A and B of R not in their
    "correct" locations, opening the door to mistakes.  But I must say
    that although I've botched HO 211 reductions, it's never been for that
    reason.
    
    For real celestial navigation I recommend using a form, but "blank
    page" sight reduction is a good training exercise.  If you're expert
    with a method, I think you ought to be able do the entire reduction by
    heart.  It sure feels good to have that ability.
    

       
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