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    Leg 67 - I give up!
    From: Paul Hirose
    Date: 2000 Jul 20, 02:47 EDT

    After wasting far too much time today on Leg 67, I'm giving up. Have
    not been able to solve the celestial fix. The problem is that only the
    zone time of the shots is given. Not having worked any of the recent
    Silicon Sea legs, I don't have the dead reckoning longitude necessary
    to convert zone time to UT.
    From the wording of the problem, I inferred that sailing 614 mi on
    course 290 would take us toward Barbados, but we wouldn't be there
    yet. So, with a small scale chart, I backed up 700 mi from Barbados on
    the reciprocal course, and took that as the assumed position for my
    sight reduction. My LOPs showed the guess was far off, but they did
    cluster well enough for me get an improved assumed position. With that
    and a larger-scale chart I re-reduced the sights. Unfortunately, the
    first two sights I reduced still had big intercepts. At that point I
    called it quits. No doubt some blunders on my part have not helped; I
    haven't done celestial in a long time.
    It seems to me you could assume ANY time zone offset from Greenwich
    and get the star LOPs to cross at a fix. Unfortunately, each time zone
    would give a different fix! But if the moon shot is good, it ought to
    resolve the ambiguity. Since the moon moves 1/2 degree per hour with
    respect to the stars, try different longitudes (hence time zone
    offsets) until the moon LOP falls on the star LOPs. That requires more
    computation than I'm willing to perform with hand work and tables.
    I'm interested to see if someone can show a NON-ELECTRONIC solution to
    the Leg 67 fix. With a computer it's so easy to play trial-and-error
    with the AP that it's not nearly as challenging.

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