Joe wrote:
Dead Reckoning

While beating into the wind you plot a series of course lines.

Why?


You cover 80 miles and plot 35 course lines.


You haven't gotten a fix in 80 miles? WTF?

How do you find a single equivalent course and distance?

Drawing a line between origin & present DR

What is that called?
What tables do you use?
How do you account for Set?

Depends- over the course of 80 miles it is very likely... a
near certainty... that the current will have changed.


How do you account for Drift?


Some DR plotters include leeway, and with a full-keel boat
that's a good idea IMHO. It should be plotted for each tack,
not overall.

If you wanted to use a landmark like a water tower 8 mi to the east of
your departure point as a departure how do you account for that.


???
Use it for what? Did you take a bearing on it? If yes, then
plot the bearing... duh. That gives an LOP, but by itself
that's not a fix. If you got bearing AND range, then that's
a fix and is plotted as such for beginning your DR track.

If my boat were sailing in an area where we had to tack
approximately every two miles, and we went 80 miles with no
fix, I'd have given the "navigator" a bootleather enema and
taken over myself long before.

Fresh Breezes- Doug King