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    A go at Silicon Sea: Leg 88
    From: Peter Fogg
    Date: 2003 Aug 13, 16:02 +1000

    > Sight Reduction and
    > Dead-Reckoning problem     Leg 88  062503   Test your knowledge!
    > ----------------------     ------  ------   --------------------
    > We are headed for Mid-Ocean Point 1 (MOP1) (40d 00.0'N  155d 00.0'W).
    > On 09/09/2002 @ 03:30:20UT our DR position was(34d 10.4'N  150d 20.2'W.
    > TC 327.4d, Speed 10 Kts, Drift 0.4 Kts, Set 273.0d. Var 15dE, Dev 1dW.
    > 1)   After 39Hours, what is the DR position?
       A:  DR N39d 40'  W154d 42'
    > --  -------------------------------------------------------
    > 2)  What is the Zone Time(ZT) and date of this DR position?
              A: 08:30:20ZT on 10 Sep 02
    > --  -------------------------------------------------------
    > Since the sky is a solid overcast, we were not able to take any
    > celestial sights. We decide to alter course for Mid Ocean Point 2
    > (MOP 2) (45d 00.0'N  118d 15.1'W).
    > 3)  What is the TC and Dist to MOP 2?
    A: from the DR, 079d TC for 1653nm.via the rhumb line
         via a Great Circle, initial course of 067d for 1634nm.
    > --  ---------------------------------
    > Var 11.0dE, Dev 1.5dW, Current Drift 0.4 Kts, Set 120d. Speed 10 Kts.
    > 4)  What is the Compass Course(CC)/Course-to-Steer to MOP 2
    >     (45d 00.0'N  118d 15.1'W)?
    A:    CC to steer 055.5d
    > --  --------------------------------------------------------
    > On this same day at a DR position of (39d 46.1'N  153d 54.8'W) at
    > 12:12:34ZT we manage a quick sight of the SUN. Var 11.0dE, Dev 1.5dW
    >       SUN LL    Hs 54d 48.1'
    > 5)  What is the Estimated Latitude line of this Sight?
    A: With an azimuth of 180d, and an intercept of 0, the latitude line
    indicated is N39d 46' (to the nearest arc minute)
    > --  ---------------------------------------------------
    > At 05:10:21UT 11/09/2002 we manage a sight of an unknown body through a
    break in the cloud cover.
    >     Bearing by Hand Compass 266.4d, appearing to be a magnitude 0.1.
    >                 Hs 33d 45.0'
    > 6)   What is the Name of this Body?
    A: Arcturus Mag 0.2  Azimuth 267d
    > --  -------------------------------
    > Using the earlier SUN sight and this Body sight for a running FIX.
    > 7)  What is the Running FIX(RFIX) position?
    A: RFix  N40d 03'  W151d 59'
    > --  -------------------------------------------------------------

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