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    Silicon Sea: Leg 43
    From: Dan Hogan
    Date: 1998 Jul 08, 4:46 AM

    Chart(s): Plotting Sheets, Bass.gif
    Beginning with this problem we will be using, The Atlas of Pilot
    Charts South Pacific Ocean, First Edition 1981.
    Sight Reduction and
    Ded-Reckoning problem      Leg 43  070898   Test your knowledge!
    ----------------------     ------  ------   --------------------
    Our last DR Position(39d 24.9'E  145 13.7'E) on 29/07/1998 @ 17:53:00.
    TC,97.5d. Log reading was 920.5mi. Var. 13dE, Dev 2dW. We have the
    755mtr mountain (39d 02.0'S  146d 17.0'E) on Wilsons Promotory within
    our visible horizon.
    While storing the sextant, after our last sight, it was dropped.
    Alignment was checked and adjusted. The index now reads 2 degrees "on
    the arc" when the horizon is aligned.
    1) What is the index correction and sign?
    -- --------------------------------------
    Ahead of us is the waypoint(39d 30.0'S  146d 00.0'E) at which we turn
    up the East Coast of Australia and head toward Sydney.
    2)  What should we expect the Log reading to be at the waypoint?
        What is our Zone Time(ZT) Estimated Time of Arrival(ETA) at
         the waypoint?
    --  -----------------------------------------------------------
    On logging in at the waypoint distance we alter course to 051d. Var
    14dE Dev 1dW.
    3)  At a Log reading 986.8mi we have a land mass visible off of the
          port beam. What is this?
        What is the DR position?
    --  -------------------------------------------------------------
    With the land broad abeam, we examine our chart, zero the Walker Log
    and set a course for a point at (38d 32.0'S  151d 00.0'E) of off Cape
    Howe. This will let us clear Gabo Island and the Cape before we can
    alter course towards Sydney.
    4)  What is the TC and Dist to this waypoint?
        What is the compass course we are steering?
        What is our Date and Estimated Time of Arrival(ETA)?
    --  ----------------------------------------------------
    In the night at 01:00:00 we make out the dark shape of land to port.
    The Log reads 324.0mi. We alter course to parallel it. But keeping
    well off shore. The Compass now reads 353d. Var 13dE, Dev 1dW.
    In the morning of 31/07/1998, Log reading 401.3mi, we manage a quick
    shot of the Sun through clouds.
     Body		Time		Hs
     Sun LL		09:35:22ZT	24d 45.6'
    5)  What is the Zn of the Sun?
        What is the Ho?
        What is the DR position?
    --  -------------------------
    Later, on the same day, we get another sight of the Sun through
    clouds. Log reading 454.5mi.
     Body		ZT		Hs
     Sun LL  	15:30:00 	16d 40.8'
    6)  What is the Running FIX(RFIX) at the time of the second sight?
    --  --------------------------------------------------------------
    Our next landmark that we need to clear is Jervis Bay. We use a
    waypoint at (35d 10.0'S  151d 00.0'E). Var 14dE, Dev 1dW. Current by
    Pilot Chart is 11Kts/day set 190.
    7)  What is the TC and Dist to this point at(35d 10.0'S  151d 00.0'E)
        from the RFIX?
    --  ----------------------------------------------------------------
    8)  What is the Compass Course Course to steer?
    --  -------------------------------------------
    Lat & Lo = XXd XX.X', Date=DD/MM/YY, HE 8 Feet, Index correction
    ??', Time hh:mm:ss in UTC/GMT. Silicon Sea is a medium displacement
    sailing vessel, 40 Feet LOA. 38 Feet LWL; Cutter rigged. Looks a lot
    like a Mason. Can tack to 45d. Dist to Horizon: Nmi = SQRT HE@mtrs x
    2.07; Nmi = SQRT HE@ft x 1.17. Water Tank = 60 gal(Imp.). Fuel Tanks =
    90 gal (Imp.). Fuel consumption .450 gal/Hr at 8.3 Kts.
    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  - psmith@wellspring.us.dg.com
            Ron Legere   - ronald.legere@yale.edu(temp. Inactive)
            Tony Severdia- anthonys@pacbell.net
            Wes Murfin   - wmurfin@onslowonline.net (Cartographer)
            John Simmonds- mobi@netconnect.com.au
            Jim Manzari  - manzari@bluewin.ch
            Buck Godwin  - bgodwin@newsguy.com (Archive Files)
            Dan Hogan    - dhhogan@lightside.com
    Dan Hogan
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