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Chart(s): Plotting Sheets, Bass.gif

NOTICE:
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?
--  -------------------------------------------

Note:
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
dhhogan@concentric.net
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