NavList:
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Silicon Sea: Leg 66
From: Dan Hogan
Date: 2000 Jun 14, 6:22 PM
From: Dan Hogan
Date: 2000 Jun 14, 6:22 PM
Chart(s): Plotting Sheet Sight Reduction and Dead-Reckoning problem Leg 66 061400 Test your knowledge! ---------------------- ------ ------ -------------------- Our Last FIX position was 11/05/2000 @ 20:21:10UT (4d 00.0'S 31d 00,1'W). Our destination is a Mid-Ocean Waypoint at (00d 00.0'N 30d 00.0'W). The current is Set 265d, Drift 0.8 Kts. Speed 10.5 Kts, Var 21dW, Dev 0.0d. 1) What is the Compass Course(CC)/Course-to-Steer for the MOP? at (00d 00.0's 30d 00.0'W)? -- ------------------------------------------------------------- 2) What is our Estimated Time of Arrival (ETA) at the MOP? In local Zone Time(ZT) In Universal Time(UT) -- ------------------------------------------------------------- Tradition has it that when crossing the Equator, the Shellback initiation take place at Noon(LAN) after crossing the Equator. Use the initial data. 3) What is the DR position at Local Apparent Noon(LAN) on this day? -- ---------------------------------------------------------------- The Navigator takes a Noon Sight at the start the Shellback ceremony. And gets the following: Sun LL 11:53:58ZT Hs 73d 54.2' 4) What is the Latitude at Local Apparent Noon? What is the Azimuth(Zn) of the Sun? -- -------------------------------------------- 5) What is the TC and Distance to Barbados(13d 10.0'N 59d 20.0'W) from the Noon Sight estimated position? -- --------------------------------------------------------------- The Pilot Chart of The North Atlantic Ocean indicates Var 19.0dW, Dev is 1.5dE. Speed 10.5Kts. Current Drift 1.0Kts, Set 285d. 6) What is the Compass Course(CC)/Course-to-Steer for Barbados? -- ------------------------------------------------------------ 7) What is the estimated Time Enroute to Barbados from our LAN estimated position?? -- ----------------------------------------------- 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 - PSmith@IMPS0014.US.DG.COM John Simmonds- johnsimmo@bigpond.com Jim Manzari - manzari@bluewin.ch Dan Hogan - dhhogan@nav.cnchost.com Dan Hogan dhhogan@nav.cnchost.com NAV-L Web Page: http://nav.cnchost.com