NavList:
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Re: Silicon Sea: Leg 71
From: Dan Hogan
Date: 2001 May 12, 12:52 EDT
From: Dan Hogan
Date: 2001 May 12, 12:52 EDT
On 11 May 2001, at 21:33, Sam Chan wrote: > Here is what I have. [Snip] > > > Chart(s): Plotting Sheets > > > > Sight Reduction and > > Dead-Reckoning problem Leg 71 050801 Test your knowledge! > > ---------------------- ------ ------ -------------------- > > > > At 18:27:00ZT @XXX.XXX6'N > > 61d 30.1'W) as we passed between the Lessor Antilles islands of St, Lucia > and > > St. Vincent. We are bound for, Mid Ocean Point(MOP1)(12d 30.0'N 70d > 00.0'W), > > in water of more than 1000 mtrs North of Aruba. This is to avoid > unfavorable > > currents along the coast. > > Dev 1.5dE, Var 12dW. Speed is 8.7 Kts, Current Drift 0.7Kts, Set 270.0d. TC > > 263.7d. > > > > 1) At the log reading of 89.6Nmi, what is the DR position? > > -- ------------------------------------------------------- > > Using Mercator sailing, DR is 13d 15.8'N 63d 08.0'W OK > > 2) At the DR position what is the celestial phenomena that is starting > > at this DR Zone Time(ZT)? > > -- ------------------------------------------------------------------- > > > For 89.6 nm @XXX.XXX Starting at 291829Q May 2001, > we are at the DR in (1) at 300447Q May 2001. This is near the start of > nautical twlight. Right > > NOTE: Sextant Index correction is on the arc 1.5d. > > > > We then take the following sights: > > > > Body UT Hs > > > > Fomalhaut 08:50:10 40d 54.7' > > Polaris 08:50:55 13d 17.3' > > Deneb 08:51:05 56d 56.3' > > Mars 08:52:03 25d 35.0' > > Venus 08:53:22 28d 13.8' > > Vega 08:53:45 45d 55.6' > > > > 3) What is the FIX position? > > -- ------------------------- > > Fix is at 13d 01.4'N 61d 28.8'W. OK > > > > The navigator has been examining nautical chart INT 400. It shows an area > > labeled the Aruba Gap (13d 50.0'N 70d 00.0'W) with a favorable current of > > 1.15 Kts. He decides to make for this waypoint. Var 12dW, Dev 1dE. Current > > Set 275d Drift 0.8 Kts. Speed 9.3 Kts. > > > > 4) What is the TC and Dist from our FIX to the Aruba Gap > > (13d 50.0'N 70d 00.0'W) > > -- ------------------------------------------------------ > > Using Mercator sailing, TC = 275.6, D=502.6 NM OK > > > > 5) What is the Compass Course(CC)/Course-to-Steer for Aruba Gap? > > -- ------------------------------------------------------------- > > > Course is 286.6C OK > > 6) What is the time enroute to Aruba Gap? > > -- -------------------------------------- > @XXX.XXX3kts, time enroute is 54h 03m OK > > 7) What is the anticipated Speed Made Good(SMG) to Aruba Gap? > > -- ---------------------------------------------------------- > > Set of the current is very close to the TC. SMG is 10Kts. OK {Snip Leg Ending] Dan Hogan dhhogan@XXX.XXX