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    Re: Silicon Sea: Leg 76
    From: Michael Wescott
    Date: 2001 Jul 09, 12:06 PM

    > We then motor to the Isla Flamenco and anchor at(08d 55.2'N 79d 31.6'W) to do
    > the final trip planning, servicing, and provisioning the boat. We will motor
    > from our anchorage to abeam the Light at Isla San Jose(08d 10.5'N 079d
    > 15.0'W). Speed 8.3 Kts. Our departure is planned for sunrise on 24/06/2001.
    > 1)  What is the Zone Time(ZT) of sunrise at our anchorage?
    >     What is the UT/GMT time of Sunrise?
    > --  ------------------------------------------------------
    Anchorage at 08d 55.2'N 79d 31.6'W. Sunrise on 24-Jun-2001 will be
    shortly after 0541 LMT. LMT is 4d 31.6' West so we add about 18 min to
    get ZT. And for GMT we add 5 hours. A close enough answer is
    0600 ZT (GMT+5)
    1100 GMT
    Wow, sitting in the Pacific further east than where I'm sitting now
    (Columbia, SC).
    > 2) What is the TC and Distance  from Our anchorage(08d 55.2'N 079d 31.6'W)
    >    to abeam of Isla San Jose Light(08d 10.5'N 079d 15.0'W)?
    > -- -----------------------------------------------------------------------
    Reading directly from the chart (or plotting sheet, in this case)
    C = 160T    D = 47.6
    > It is late in the season and the North Pacific storms are beginning so we
    > elect to bypass the Galapagos Islands. We will follow the recommendations in
    > Ocean Passages For The World and in World Cruising Routes and on departing
    > Isla San Jose Light(08d 10.5'N  79d 15.0'W) we will head for a Mid-Ocean
    > Point(MOP) at (03d 00.0'N  110d 00.0'W).
    Why so far south? To avoid the storms? Don't we risk light winds so far
    > 3) What is the TC and Distance to the MOP at (03d 00.0'N  110d 00.0'W)
    >    from Isla San Jose Light(08d 10.5'N  79d 15.0'W)?
    > -- ------------------------------------------------------------------
    Using M.P.:           C = 260.4T   D = 1861.9
    Using M.L. (5d30'):   C = 260.4T   D = 1862.6
    Using GC:            IC = 262.1T   D = 1861.5
    > From the MOP(03d 00.0'N 110d 00.0'W) we head to make landfall on the
    > Southwest coast of Hawaii(19d 30.0'N 154d 45.0'W). We have two alteratives
    > depending on current and weather, either a Great Circle Course or the Rhumb-
    > Line course.
    > 4)  Calculate the Rhumb Line TC and Distance to landfall.
    >     Calculate the Great Circle initial course and Distance to landfall.
    > --  -------------------------------------------------------------------
    Rhumb Line (M.P.):    C = 290.5   D = 2820.2
    Great Circle:        IC = 294.2T  D = 2801.1
    > 5) To the nearest tenth of a day, what are the total days enroute from our
    >    anchorage at Isla Flamenco to the Southwest coast of Hawaii as our plan is
    >    layed out? Sailing Speed 9.5 Kts, motoring Speed is 8.3 Kts:
    >     Isla Flamenco (08d 55.2'N 79d 31.6'W)
    >     Isla San Jose Light(08d 10.5'N 079d 15.0'W)
    >     Mid-Ocean Point(MOP) at (03d 00.0'N  110d 00.0'W)
    >     Southwest coast of Hawaii(19d 30.0'N 154d 45.0'W)
    > -- ------------------------------------------------------------------------
    For planning purposes we'll use the longest (Rhumb Line) and slowest (8.3 knot,
    199.2 nmi/day).
    Leg 1:   47.7
    Leg 2: 1861.9
    Leg 3: 2820.2
    Total  4729.8 which is 23.7 days
    > Having a 6 person crew and water consumption at 1.5 US Gal/day per person.
    > 6)  What is the expected water consumption for the trip to Hawaii?
    > --  --------------------------------------------------------------
    213.3 gal
    > 7) Estimating 3lbs of food per day per person what is the total weight
    >    in food for the trip?
    > -- -------------------------------------------------------------------
    Twice the water. 426.6 lbs.
            Mike Wescott

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