NavList:
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Silicon Sea: Leg 50
From: Dan Hogan
Date: 1999 Mar 30, 13:10 EST
From: Dan Hogan
Date: 1999 Mar 30, 13:10 EST
Chart(s): Plotting Sheet / any Atlas
Sun Sight &
Dead-Reckoning problem Leg 50 033099 Test your knowledge!
---------------------- ------ ------ --------------------
Last FIX position (35d 52.0'S 170d 48.4'E) 09:05:22 @XXX.XXX
TC 150.8d, speed 9.4 Kts. Var 20dE, Dev 3dE. We are sailing under a
solid low overcast. At 0800ZT 20/02/1999 we have land to port.
1) What is the DR position at 0800ZT?
-- ----------------------------------
At 13:45:00ZT the same day we manage a quick shot of the lower limb of
the Sun.
Hs 60d 00.2'
2) What is the Sun's Zn?
-- ---------------------
At 18:10:10 me manage another lower limb Sun sight.
Hs: 12d 54.4'
3) What is the Running Fix position from the previous Sun sight?
-- ------------------------------------------------------------
We set a course to a point(40d 00.0'S 174d 15.0'E) that is of off the
Mt. Egmount headland. Var 20dE, Dev 3dE, Current set 15d, drift 15 Kts
per day. We are making 10 Kts close hauled on a port tack.
4) What is the TC and Dist. to this point?
-- ---------------------------------------
5) What is the Compass Course(CC)/Course-to-Steer?
-- -----------------------------------------------
6) What is our Estimated Time of Arrival at the waypoint?
-- ------------------------------------------------------
7) What is the time of Sunset at the(40d 00.0'S 174d 15.0'E)
waypoint?
-- ----------------------------------------------------------
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 Simmonds- mobi@XXX.XXX
Jim Manzari - manzari@XXX.XXX
Dan Hogan - dhhogan@XXX.XXX
Dan Hogan WA6PBY
dhhogan@XXX.XXX
Catalina 27 "GACHA"
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