NavList:
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Silicon Sea: Leg 65
From: Dan Hogan
Date: 2000 Jun 01, 2:26 PM
From: Dan Hogan
Date: 2000 Jun 01, 2:26 PM
Chart(s): Plotting Sheet Sight Reduction and Dead-Reckoning problem Leg 65 060100 Test your knowledge! ---------------------- ------ ------ -------------------- On 09/05/2000 @ 14:05:13UT, with a Noon Sight(LAN), we had an Estimated Position of (13d 10.9'S 32d 12.7'W). We are headed for our Mid-Ocean Waypoint 2(MOP2) (00.00dN 30d 00.0'W) to cross the Equator. TC 009.5d, Speed 10.5Kts. Var 21dW, Dev 0.0dW. We have logged 504 mi since our Noon Sight. 1) What is the DR position? -- ------------------------ 2) What is the UT Date and Time of our DR at the 504 mi? What is the Zone Time(ZT)? -- ----------------------------------------------------- 3) What is the celestial event that occurs at about 17:57:00ZT? -- ------------------------------------------------------------- 4) What is our DR position at the time of this celestial event? -- ------------------------------------------------------------- Body UT Hs Moon LL 20:20:05 68d 01.5' | UNKNOWN 20:21:10 46d 07.5' Arcturus 20:22:45 18d 02.2' Spica 20:23:30 33d 43.4' Miaplacidus 20:24:10 24d 15.2' Dubhe 20:25:30 22d 28.9' 5) One of the above bodies is unsuitable for a sight. Which body and Why? -- --------------------------------------------------------- 6) What is the name of the UNKNOWN bright Star half way up from the horizon bearing 270.0d by the steering compass? -- ---------------------------------------------------------------- 7) What is our FIX position at the time of the first Sight Reduction? -- ------------------------------------------------------------------ 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