NavList:
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Silicon Sea: Leg 64
From: Dan Hogan
Date: 2000 May 10, 09:50 EDT
From: Dan Hogan
Date: 2000 May 10, 09:50 EDT
Chart(s): Plotting Sheets
Sight Reduction and
Dead-Reckoning problem Leg 64 051000 Test your knowledge!
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Our last position FIX(21d 05.0S 33d 30.9W) 07/05/2000 @ 05:18:58UT at the
shoal off the Brazilian coast. The sky is overcast with scattered rain. We
are headed for our Mid-Ocean Waypoint 2(00d 00.0'N 30d 00.0'W), to cross
the equator. Speed 10.5Kts, TC 009.3d, Dist 1282.0 mi. Current Drift
0.7Kts, Set 175d. Var.24DW, Dev 00.0d.
We maintain course and speed until our Log reads 480 elapsed miles since
out last FIX position.
1) What is the DR position at the 480 mi position?
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2) What is the Compass Course(CC)/Course we have been steering by
our compass?
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3) What is the Speed Made Good(SMG) on this course?
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At Noon on the day of our 480 mi Log the clouds break up and we manage a
Noon(LAN) sight of the Sun Lower Limb.
4) What is the Latitude?
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At this time we also sense a change in the current drift. A quick look at
the Pilot Chart of the South Atlantic tells us we have entered the
Equatorial current from Africa. Drift 0.7Kts, Set 54d. Var 23dW, Dev 0.0d.
5) What is the TC and Distance to Mid-Ocean Point 2(00d 00.0'N 30d 0.0'W)?
-- -----------------------------------------------------------------------
6) What is the Compass Course(CC)/Course-to-Steer to MOP2?
-- -------------------------------------------------------
7) What is the Estimated Time and date in UT of our Arrival at MOP2
(00d 00.0'N 30d 00.0'W) from our NOON position?
What is the Zone Time(ZT) of the ETA?
-- ----------------------------------------------------------------
8) Who is the historical figure that presides over the ceremony of
crossing the Equator and what are the initiates called?
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NOTE:
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@XXX.XXX
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@XXX.XXX
John Simmonds- johnsimmo@XXX.XXX
Jim Manzari - manzari@XXX.XXX
Dan Hogan - dhhogan@XXX.XXX
Dan Hogan
dhhogan@XXX.XXX
NAV-L Web Page: http://nav.cnchost.com
