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    Silicon Sea : Leg 69
    From: Dan Hogan
    Date: 2001 Apr 04, 11:19 AM

    This leg uses the year 2000 Nautical Almanac. The next Leg will use the
    year 2001 Nautical Almanac.
    Chart(s): Plotting Sheet
    Dead-Reckoning problem     Leg 69  040401   Test your knowledge!
    ----------------------     ------  ------   --------------------
    The last DR position was(10d 27.9'N  52d 26.4'W) on 18/05/2000 @
    Our Speed has been 10.7 Kts, TC 288.9d Var 19dW. Dev 1.5dE. Current Set
    Drift 0.5Kts.
    On that evening we take the following sights:
            Body            UT                                      Hs
            Sirius      22:15:30                    28d 16.3'
            Spica           22:17:02            42d 20.6'
            Avior           22:19:00            15d 55.3'
            Bellatrix       22:19:45            13d 26.5
            Dubhe           22:20:12            37d 56.1'
    1)  What is our FIX position?
    --  -------------------------
    |2)  What is the TC and distance to Barbados(13d 10.0'N  59d 20.0'W)?
    --  ----------------------------------------------------------------
    |We continue sailing maintaining the same speed and True Course with an
    sky. Then, with the navigator on deck waiting for an opening for a Sun
    shot, we
    see a spot of land on the horizon ahead. It is 20/05/2000 @ 12:13:00ZT.
    3)  What is the DR position?
    --  ------------------------
    4)  What day of the week is this?
    --  -----------------------------
    We want to enter Barbados at Bridgetown, on the Southwest side of the
    island. We alter course to a Waypoint(12d 56.0'N  59d  30.0'W) that will
    clear us of shallows off the South end of the island.
    5)  What is the TC and Dist to this Waypoint?
    --  -----------------------------------------
    6)  What is our Estimated Time of Arrival(ETA) at the Waypoint in
        Zone Time(ZT)?
    --  -------------------------------------------------------------
    After arriving at our waypoint we plot a TC of 318d to take us in and
    clear of Needham Point before entering Carlisle Bay at Bridgetown.
    Var 15dW, Dev 1dE, Speed 10.0Kts, Current Set 270d Drift 1.5Kts.
    7)  What is the Compass Course(CC)/Course-to-Steer?
    --  -----------------------------------------------
    Lat & Lo = XXd XX.X', Date=DD/MM/YY, HE 9 Feet, Index correction
    -2.5', Time hh:mm:ss in UT,unless otherwise stated. Silicon
    Sea II is a 34,000 lb(15.40t) displacement sailing vessel, 48' 3"
    (14.70m) LOA. 39' (12.00m) LWL; Cutter rigged. Can tack to 45d.
    Water Tanks = 220 gal(1000 ltrs). Fuel Tanks = 155 gal(700 ltrs).
    Fuel consumption .675 gal/Hr at 8.5 Kts. DR(Ded-Reckoning)=position
    by sailings, EP(Estimated Position)=DR+current affect. Dist to
    Horizon: Nmi = SQRT HE@mtrs x 2.07; Nmi = SQRT HE@ft x 1.17.
    PLEASE respond with your results and thinking on these exercises to
    the NAVIGATION list at large. If you have questions or problems, A
    lot of folks on the list are knowledgeable and willing to help. Any
    questions or doubtful areas will be responded to promptly. Let us
    hear from you soon!
    Good Navigating!
       -=The Navigation List Working Group=-
            Peter Smith  -   Smith_Peter@EMC.COM
            John Simmonds-   johnsimmo@dingoblue.net.au
            David Weilacher- daveweilacher@earthlink.net
            Tony Cappiello-  cappiello@kearfott.com
            Frank Norris-    NORRIS_FRANKLIN_H@LILLY.COM
            Dan Hogan    -   dhhogan@veriomail.com
    Dan Hogan

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