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    Re: No DR position. How can you get an accurate celestial fix?
    From: Bill Lionheart
    Date: 2020 Jan 21, 11:43 +0000

    As the standard approach uses a linear approximation I have an idea if
    you start from any guess of the position and iterate this is
    equivalent to Newton's method for solving non-linear equations by
    successive linearization. Presumably there is a paper somewhere that
    says how close to the true position you have to be for convergence?
    
    Bill
    
    On Mon, 20 Jan 2020 at 19:03, Dustin Baenen  wrote:
    >
    > http://fer3.com/arc/m2.aspx/Can-I-Navigate-Without-an-Assumed-Position-Baenen-aug-2017-g39877
    >
    > Here is a link from the 2017 thread mentioned earlier.  There is alot of 
    good info in it.  My amateur advice would be to start with your best guess of 
    a D/R (Last known fix, or just make one up like Moitessier did) and do 
    several iterations of your sight reduction using the resulting fix as a new 
    assumed position.  Within a few iterations the LOP's will stabalize around 
    your true position.
    >
    > db
    >
    > 44.30N, 88.00W
    >
    > View and reply to this message
    

       
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