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    Re: Level of observation accuracy in medium seas
    From: Robert Gainer
    Date: 2004 Jul 24, 01:13 +0000

    Jared  said,
    More to the point, wouldn't the difficulty in tracking where you thought the
    horizon might be (as you rolled up and down) create more uncertainty in
    where the horizon was? Unless the swells were very gentle and the boat a
    large ship?
    I am not quite sure what you are shooting for in this statement. When you
    are in the trough of the wave you can�t see anything except the top of the
    next wave. You are below sea level by, say maybe 30 feet. At the top of the
    wave when you are looking though the scope you can�t see what�s happening
    around you, you just line things up as best you can and when you feel the
    seat of your pants rise above the cabin top and you get the weightless
    feeling you know the boat has started the trip back down and this is the
    time to call mark, ready or not.  Each time you do this you are reacquiring
    the horizon, not tracking it. So if a larger wave then the one you are on is
    within, say 2 miles you will �see� that as the horizon. The conditions I use
    as an example are from my trip that went into Hurricane Gloria in October of
    1976 with 90 knots wind speed. This was with a 31 foot Brit Chance designed
    sailboat, the �Chance 30-30�.
    All the best,
    Robert Gainer
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