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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
