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    Re: Fix Maximum Probability Positions
    From: Greg Rudzinski
    Date: 2013 Mar 25, 14:11 -0700


    The first EP is obtained after an unknown amount of DR. The first R.Fix establishes a position. The second R.Fix position gives enough information to now correct for cross track error. The red DR course is just another way to plot until a position is obtained. Course steered and speed through the water are constant for this example. Course made good and speed made good aren't known until the second R.Fix.

    Greg Rudzinski

    Re: Fix Maximum Probability Positions
    From: John Karl
    Date: 2013 Mar 25, 12:29 -0700
    I'm not sure I understand your running fix plot. It looks like:

    Your plotted the 900 EP from your 900 DR by applying a eastward correction (current drift maybe).
    Then likewise at 1100 your DR moved eastward again to an EP at 1100, where the 1100 sun line just perfectly matched the 1100 EP.

    Am I reading this right?

    If so, you gave an example with no estimation error. In which case both the estimated-position running fix and the traditional running fix give identical results.

    john K
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