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    Re: Sextant Positions versus Map Datums?
    From: Brian Whatcott
    Date: 2002 Jan 19, 10:23 PM

    >>>NAD 83 --  30:16:28.82N, 97:44:25.19W --or-- 30d16m28.77992N,
    >>>NAD-27 --  30:16:28.03N, 97:44:24.09W
    >>>WGS-72 --  30:16:28.68N, 97:44:25.75W
    >For what it's worth, here is the correspondence between
    >WGS72, NAD27 for CONUS (one of numerous NAD27 bases)
    >and NAD83 for that general area, as given by the waypoint
    >depicted in these datums by the Garmin GPS40:
    >NAD27 CONUS  N30 16 28.2 W097 44 24.1
    >WGS72               N30 16 28.8 W097 44 25.2
    >NAD83                N30 16 28.9  W097 44 25.2
    For those still interested in the challenges of relating fixes
    made relative to the celestial sphere to charts plotted on some
    oblate figure related to a North American equivalent sea level surface like
    the North American datum of 1927 (NAD27) or the oblate world surface used
    for the North American Datum of 1986 (NAD83), it may be useful to consult
    this note that Bill Strange  wrote up last year.
    THE PROBLEM WITH NAD 27 - By Bill Strange, NGS (Ret.)  dated Dec 2001
    [I provide below the URL for the Google html cache to avoid difficulties
    for people who do not have a pdf viewer installed.]
    Brian Whatcott
       Altus OK                      Eureka!

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