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    Re: Fix Maximum Probability Positions
    From: Gary LaPook
    Date: 2013 Mar 21, 22:49 -0700
    For a real life example of running fixes see:

    https://sites.google.com/site/fredienoonan/discussions/navigation-to-dakar

    which illustrates four running fixes plotted by Fred Noonan in 1937 while navigating Earhart's plane across the South Atlantic. I have added error bands to each of his LOPs starting with +/- 7 NM and growing at the rate of 13 knots, 10% of the distance traveled each hour. Noonan advanced his 1341 sunline and his last plotted running fix is at 1800 Z by which time the band of uncertainty in the advanced 1341 Z LOP had increased to +/- 63 NM.

    gl

    --- On Thu, 3/21/13, David Fleming <d.l.fleming.1---.com> wrote:

    From: David Fleming <d.l.fleming.1---.com>
    Subject: [NavList] Re: Fix Maximum Probability Positions
    To: garylapook---.net
    Date: Thursday, March 21, 2013, 7:56 PM


    JK,

    Until we adopt a common plotting standard it is impossible to evaluate the logical consistency of any running fix process.

    Why should we judge running fixes using estimation theory, I just want to know where I think I am.

    Of course your running fix violates Bayesian theory. When you show EP1 but not DR1 you have left out information. Given that start, which violates Bayesian Theory without having even mentioned a running fix, how can I trust your conclusions?

    Imagine your boat sinks just as you get an LOP. Would you settle for giving the Coast Guard your EP. I wouldn't. I would want them to know were the DR is also if nothing else than to know intercept and orientation of my LOP. ( Do not think I'm considering St. Hillaire only.)

    I might find you commentary on Running Fixes interesting if you could explain what problem you have with Running Fixes as generally applied.

    DF
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