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    Re: AN5954 bubble octant by Bausch and Lomb
    From: Gary LaPook
    Date: 2012 May 9, 01:10 -0700
    Well that is the entire point.  Bubble sextants were developed for use in flight and the accelerations in the plane cause large excursions in the instantaneous measured altitudes, it can vary more than a degree! Since these are random variations, taking the average or the median improves the final result. There is a reason that all the octants developed in the 1930s and used by airlines for primary oceanic navigation through the late 1960's and by the U.S. Air Force though the early years of this century all incorporated an averager.

    gl

    gl
    --- On Tue, 5/8/12, Alexandre E Eremenko <eremenko---.edu> wrote:

    From: Alexandre E Eremenko <eremenko---.edu>
    Subject: [NavList] Re: AN5954 bubble octant by Bausch and Lomb
    To: NavList@fer3.com
    Date: Tuesday, May 8, 2012, 4:52 PM

    Gary,

    ...

    Now let me repeat what I claimed: if you shoot accurately enough so that
    your altitude changes monotonically, or almost monotonically,
    taking median is the same as taking the middle observation and rejecting
    the rest. Then why bother shooting several times?
    The median is not better than one shot.

    It only makes sense when your single shot accuracy is bad,
    worse than the change of the altitude between the shots,
    as it happens in your first series, which is not monotone.

    Alex.
       
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