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