NavList:
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Silicon Sea: Leg 79
From: Dan Hogan
Date: 2001 Sep 17, 7:38 AM
From: Dan Hogan
Date: 2001 Sep 17, 7:38 AM
Chart(s): Plotting Sheets
Sight Reduction and
Dead-Reckoning problem Leg 79 091701 Test your knowledge!
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Our last FIX position was (03d 00.00'N 082d 00.0'W) @ 10:51:11UT @
26/06/2001. We are sailing toward MOP1(03d 00.0'N 110d 00.0'W) where
we will turn and head for Hawaii.
At a Log distance traveled of 710.5 Nmi from the FIX position. TC 270.0d,
Speed 10.0 Kts, we determine that we have entered the Equatorial Counter
Current.
1) What is the DR position on entering the Equatorial Counter Current?
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On the morning of 30/06/2001 we manage the following sights:
Body UT/GMT Hs
Fomalhaut 11:53:00 54d 01.8'
Deneb 11:55:10 30d 03.8'
Altair 11:57:20 27d 35.1'
Saturn 11:59:05 23d 17.4'
Venus 12:04:11 38d 50.8'
2) What is the DR position at the time of the Fomalhaut sight?
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3) What is the position FIX?
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TC 270.0d, Speed 10.0 Kts, Current Drift 1.0 Kts, Set 280.0d. Var 2.0dE,
Dev 1.5dE.
4) What is the Compass Course(CC)/Course-to-Steer to MOP1(03d 00.0'N
110d 00.0'W) from the FIX position?
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5) What is the distance to MOP1(03d 00.0'N 110d 00.0'W)?
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With all times rounded to the nearest whole minute.
6) What is the UT day and date of our ETA at MOP1?
What is the Zone Time(ZT) and date of our ETA at MOP1?
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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@mtrs x 2.07; Nmi = SQRT HE@ft x 1.17.
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 - Smith_Peter@EMC.COM
John Simmonds - johnsimmo@dingoblue.net.au
Tony Cappiello - cappiello@kearfott.com
Frank Norris - NORRIS_FRANKLIN_H@LILLY.COM
Sam Chan - schan@socal.rr.com
Mike Wescott - wescott_mike@EMC.COM
Dan Hogan - dhhogan@veriomail.com
Dan Hogan
dhhogan@verionmail.com
