NavList:
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Silicon Sea: Leg 53
From: Dan Hogan
Date: 1999 May 19, 09:39 EDT
From: Dan Hogan
Date: 1999 May 19, 09:39 EDT
Chart(s): Plotting Sheet
Sight Reduction and
Dead-Reckoning problem Leg 53 XXXXXX Test your knowledge!
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We depart Wellington, New Zeeland(41d 30.0'S 175d 20.0'E) at Sunrise
on 06/03/1999. Var 18dE, dev 2.5dW. Set 170d, drift 10 Kts/day. At
02:52:20 Hrs after departure we take the following bearings for a
departure position using a Hockey Puck handbearing compass purchased in
Wellington.
Mt. Ross, 983mtrs(41d 27.5'S 175d 20.0'E): 342.0d
Mt. Tapuaepuku 2885mtrs(42d 00.0'S 173d 48.8'E):240.4d
1) What is the GMT time of the Departure FIX?
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2) What is the departure FIX position?
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It would be interesting after plotting the bearings for Q2 on your
plotting sheet and then work them using your favorite DR Sailings
method.
3) What is the rhumb line TC and distance from our Departure FIX
to the Trans Ocean Point 1(49d 00.0'S 170d 00.0'W)?
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The distance log on the Knotmeter read 27 mi at the time of the FIX.
4) Since our departure from Wellington, what is the calculated DR time
in hours to the Trans Ocean Point 1?
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Var, Dev, and current still the same.
5) What is the Compass Course/course-to-steer for Trans Ocean Point 1?
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At evening we manage the following sights.
Body GMT Hs
Bellatrix 07:30:00 40d 34.0'
Acrux 07:31:10 35d 23.6'
Procyon 07:31:22 39d 01.7'
Rigil Kentaurus 07:31:31 21d 47.8'
Miaplacidus 07:32:10 54d 16.7'
Saturn 07:32:33 11d 55.6'
6) What is the best FIX position?
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Current Set 175d Drift 10Knts/day. Var. 17dE, Dev 2.5dW
7) What is the Compass Course(CC)/course-to steer to Trans Ocean
Point 1(49d 00.0'S 100d 00.0'W)?
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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 UTC/GMT,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@mtrs x
2.07; 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 K Simmonds - johnsimmo@XXX.XXX
Jim Manzari - manzari@XXX.XXX
Dan Hogan - dhhogan@XXX.XXX
Dan Hogan
dhhogan@XXX.XXX
