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    Resetting clocks on big ships
    From: Russell Sher
    Date: 2000 Jul 20, 1:36 AM

    Last year we travelled to St. Helena Island from Cape Town on the RMS St.
    Helena. An interesting point about changing of the ship's clocks is that the
    noon-to-noon run and resulting average speed is calculated from 1200 to
    1200, ignoring any changes to the clock as time zones are crossed. i.e. the
    noon-to-noon run may be 23 hours or 25 hours on certain days, depending upon
    which direction the vessel is travelling. Even at the start of the voyage
    which began at about 1600 local time, the first noon-to-noon position and
    average speed announcement was based upon 20 hours. (so that the average
    speed didn't figure against the distance covered, until one realised that it
    was calculated by dividing the distance by 20 not 24).

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