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Subject: Older Silicon Sea results
From: Ed Falk (Ed.Falk@XXX.XXX)
Date: Tue Jul 06 1999 - 13:49:51 EDT
Hi all; I've been going through the older Silicon Sea legs and
am having problems getting some of them to reconcile.
For instance, leg 49 gives the following problem:
Our last position FIX was at (35d 00.2'S 156d 59.7'E) at 09:05:22
@XXX.XXX Current
Drift 17 mi/day, set 185 according to the Pilot Chart. We continue
on course through the night. The weather is deteriorating and it
begins to rain. At 19:45:00GMT the wind heads us and we are forced
to change our Compass Course(CC) 45d to port to stay close-hauled.
As I read it, the last sentence means we turn 45 degrees to port,
to a new true heading of 86.8 - 45 = 41.8. However, Answers.txt
says the new True Course Made Good is 72 degrees. The current can't
be *that* strong. Have I made a mistake somewhere? Even assuming
that the puzzle meant to say that we turn port to a compass course of
45 degrees mag., that gives me a TC of 60 degrees, and after factoring
in the current, CMG = 64 degrees @XXX.XXX
The second part of the puzzle gives this table:
TC Speed Dist Time/in/Hrs
072d 8.7 91.3 10:30:00
027d 8.7 52.2 18:30:00
122d 7.5 198.1 26:25:00
095d 9.5 311.1 32:40:00
I don't quite know how to read this. Are the distances & times
cumulative? I don't see how that can be, since the second distance
is a smaller number than the first. However, I find it hard to
believe that it took 18:30 to travel 52 miles @XXX.XXX
I had problems with the first part of the puzzle too, where it asks
for the DR position at the time of course change. I did it with
plotter and paper and via computer and got roughly the same answer
(35°3'S, 158°53'E), but Answers.txt gave 34°54.7'S for the
lattitude.
How do I determine Zone Time from lat,lon? Is there a chart I'm
missing?
I'm convinced there are at least some errors in Answers.txt. For
instance, in Leg 46, the answer to question 1 about total
distance is 114,112.8 mi which I'm pretty sure is wrong. Even
*I* don't get that lost.
Thanx in advance for any advice you can give.
-ed falk
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