# NavList:

## A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

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Older Silicon Sea results
From: Ed Falk
Date: 1999 Jul 06, 13:49 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?S, 158?'E), but Answers.txt gave 34?.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
distance is 114,112.8 mi which I'm pretty sure is wrong.  Even
*I* don't get that lost.
-ed falk
```
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