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    Re: Finally, a reasonable explanation for Earhart's failure to find Howland
    From: Gary LaPook
    Date: 2013 Feb 25, 21:32 -0800
    Yes, those are two hypothetical fixes that provide an explanation of the failure to find Howland.

    10 NM is taken as the uncertainty in normal in-flight celestial fixes but, if there is turbulence, the errors can be much greater. Considering the flight altitude reported by Earhart and her reports of overcast conditions at the same time indicates high clouds, conditions associated with turbulence. See:

    https://sites.google.com/site/fredienoonan/topics/accuracy-of-celestial-fixes

    Last June I did a test flight and took two observations of the moon, one had an error of plus 6 NM the other of minus 6 NM, and the flight conditions were extremely smooth so it is not unusual to see large differences in opposite diretions. See:

    http://fer3.com/arc/m2.aspx/Moon-observations-flight-LaPook-jun-2012-g19791

    Also see the flight navigation information available at:

    https://sites.google.com/site/fredienoonan/

    gl





    --- On Sun, 2/24/13, Andrew Nikitin <nsg21@hotmail.com> wrote:

    From: Andrew Nikitin <nsg21@hotmail.com>
    Subject: [NavList 22477] Re: Finally, a reasonable explanation for Earhart's failure to find Howland
    To: garylapook@pacbell.net
    Date: Sunday, February 24, 2013, 9:52 AM


    > I finally DO have an explanation

    Just to make sure, those fixes at 1623 and 1700, one 10 NM north of track, another 10 NM south are completely hypothetical, right? They are there to explain how normal (=not too excessive) uncertainty in a fix caused enough of course uncertainty to intercept landfall LOP way farther north than expacted.

    Also, as much as i understood the text, 10 NM error is a borderline of what is considered "normal".
    So, in your experience, how likely it is to have 2 "borderline normal" fixes in a row, one missing in one direction, another missing in another direction?

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