NavList:
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Silicon Sea: Leg 35
From: Dan Hogan
Date: 1997 Oct 01, 4:24 AM
From: Dan Hogan
Date: 1997 Oct 01, 4:24 AM
This is Leg 35. I am going to do some upgrading to my computer so I will be offline for a day or two. ************************************* Chart(s): maldive1.gif, Plotting Sheet Dead-Reckoning problem Leg 35 100197 Test your knowledge! ---------------------- ------ ------ -------------------- At Mali' Atoll in the Maldive Islands we restock our supplies and do what maintenance the boat requires. We find that water is available in 11 Litre bottles. Our estimated consumption for a crew of 6 is 1.5 gal/day per man. Our departure point from Mali' is at(4d 10'N 73d 30.0'E). So far this will be the longest open water passage made. Looking at the Pilot Charts we see Cocos/Keeling Island at(12d 02.0'S 97d 00.0'E). We elect to pass within view of Cocos/Keeling Island as a navigation check. Planning speed is 7 Knots. Waypoints: Cape Leeuwin 34d 15.0'S 115d 06.0'E Turn to Bass Strait 38d 54.0'S 120d 00.0'E Bass Strait 39d 18.0'S 144d 00.0'E Turn to Sydney 38d 00.0'S 150d 20.0'E Syndey Harbor 33d 50.0'S 151d 20.0'E Distance and quantity answers to the nearest 0.1 are sufficient. 1) How many planned days are there from Mali' departure to Sydney Harbor? -- -------------------------------------------------------------- We fill the main water tank and have four 5 U.S. gal containers remaining. 2) What is the estimated additional water required in US gallons? How many 11 Litre bottles is this? -- -------------------------------------------------------------- We manage to store 42 bottles througout the boat. 3) How many Litres are we short? How many US gallons are we short? -- --------------------------------- Prior to departure we swing the compass and find that the deviation is 4dW. The variation is 4dW. Current is 10 Kts setting 145d. We have a Force 3 wind from 200d. We plot our leg to Cocos/Keeling Island. 4) From our departure point(4d 10.0'N 73d 30.0'E) what is the course to steer (Compase Course CC) for Cocos/Keeling Island(12d 02.0'S 97d 00.0'E)? What is the TC? -- ------------------------------------------------------------------ 5) How many hours is it to Cocos/Keeling Island? -- --------------------------------------------- We depart Mali' on 07/07/1996 at the Zone Time (ZT) of Sunrise(SR). 6) Based on the interval between Sunrise the End Civil Twlight(ECT) and our SMG; what is the expected Dead Reckoning(DR) position at ECT? -- -------------------------------------------------------------------- 7) What is the Zone Description(ZD) at the ECT DR position? -- -------------------------------------------------------- 8) What is the GMT at the End Civil Twlight (ECT) DR position? -- ----------------------------------------------------------- Note: Lat & Lo = XXd XX.X', Date=DD/MM/YY, HE 8 Feet, Index correction -.2', Time hh:mm:ss in UTC/GMT. Silicon Sea is a medium displacement sailing vessel, 40 Feet LOA. 38 Feet LWL; Cutter rigged. Looks a lot like a Mason. Can tack to 45d. Dist to Horizon: Nmi = SQRT HE@mtrs x 2.07; Nmi = SQRT HE@ft x 1.17. Water Tank = 60 gal(Imp.). Fuel Tanks = 90 gal (Imp.). Fuel consumption .450 gal/Hr at 8.3 Kts. 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@wellspring.us.dg.com Ron Legere - ronald.legere@yale.edu Tony Severdia- anthonys@pacbell.net Wes Murfin - wmurfin@onslowonline.net (Cartographer) John Simmonds- mobi@netconnect.com.au Dan Hogan - dhhogan@lightside.com Dan Hogan WA6PBY Yacht GACHA West Covina, CA Catalina 27 dhhogan@lightside.com San Pedro, CA =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-= =-= TO UNSUBSCRIBE, send this message to majordomo@ronin.com: =-= =-= navigation =-= =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-=