NavList:

Dead-Reckoning problem Leg 91:

PART 1

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Our last position A Running FIX(36d 27.4'N 126d 56.3'W) was on 17/09/2002
@ 02:11:20UT. The clouds have thickened and a fog is building. We have traveled
310.5 Nmi since the RFIX Position.

TC 112.1d, Speed 10.0 Kts.

We are headed for MOP4(34d 20.0'N 120d 33.0'W) at the entrance to the Santa
Barbara Channel in Southern California.

1) What is the DR position at the end of the 310.5 Nmi run?

ANS: 34d 30.6m N, 121d 4.6m W (by Mercator)
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2) What is the Zone Time at the DR position?

ANS:  The run has been 31.05 hours long starting at 02:11:20UT so it will now be
           2:11:20 +7.05hrs or 09:11:23 hoursUT.
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3) From the DR position, what is the TC and distance to MOP4(34d 20.0'N
    120d 33.0'W)?

ANS: 112d  28.3Nm (Mercator)
         112d  (initial course) 28.1 (Great Circle)
          112.1d  28.1Nm (Mid-Latitude)
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PART 2

<<<Sailing in a thick fog we >> irrelevant distraction.

<<At 04:20:10ZT we are 5.6 miles West, abeam of Richardson Rock
(34d 01.2'N 120d 06.2'W). >>

I'm confused here. I'm showing Richardson Rock at 34d 06.266m N , 120d 31.202m W on Chart 1444000, "Point Arena to the Mexican Border".  Is the question saying "We are at this position which is 5.6nm W of Richardson Rock" or is it saying "We are 5.6nm W of Richardson Rock, which is at this position". ?? To rephrase the question, is the given position supposed to be the vessel, or the rock?

I'll stop here to await clarification on that.

And, incidentally, were we still supposed to be on the track from Part 1? Should that be assumed or ignored? (At this point I've been calculating, not plotting.)

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