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    Re: Interpolation to latitude
    From: Joe Schultz
    Date: 2009 Nov 12, 13:01 -0800

    Hi George,
    Sorry about the delay - was busy with the American Veteran's Day holiday.  I'm 
    going to answer in a 'round-a-bout way; the intent is to not confuse Inuik.  
    This is his series of postings.
    1. We no longer operate in an LMT world, and very few living people remember 
    what that was like.  Instead, we operate in a zone time world.  As an 
    example, I listen to BBC radio news.  They always state the time in GMT.  I 
    then mentally subtract six hours to get my local zone time, then glance at my 
    watch (to confirm my sums).  It's a natural process for me because I've never 
    lived in an LMT world, and I see no reason to switch worlds when navigating.  
    I fail to understand why the navigation schoolbook authors want us to switch 
    back and forth and, in my opinion, they are confusing their readers.
    2. The daily pages of a paper nautical almanac are very elegant.  Enter the 
    daily pages with approximate time (left side) or position (right side), then 
    extract position (left) or time (right) data.  Then apply some form of 
    latitude and longitude corrections to get "exact" position or time.  And the 
    daily pages operate in a zone time world, just like we do in our daily lives.
    My solution method for Inuik's exercise takes advantage of both statements.  
    No need to bend our minds around the concept of operating in an LMT world.  
    The attached Inuik_2.gif is my complete solution.
    Inuik, get ready.  I'm going to ask you "why is it OK to interpolate for the 
    LAT CORRN?"  But I'll wait until you tell me that you understand how to apply 
    the LON CORRN.  And don't hurry.  If you get a good handle on these 
    calculations then the rest of the almanac's daily page will fall into place 
    for you.
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