NavList:

The Vertical Sextant.
This tip will enable even the inexperienced celestial navigator to plot
celestial (pinwheels on the chart by using a simple sextant technique.
In 1958, 1 was stationed on a Liberty ship of World War II vintage. For months
at a time for five years, the ship was under way approximately 200 miles off
the East Coast
Using Loran ?A? and the sextant to maintain radar, air craft and missile
tracking station. The duty was a pleasure for a celestial navigation nut like
myself because in any month I observed, computed, plotted and evaluated an
average of 20 morning and evening star fixes, plus countless sun lines.
The best fixes were always when the horizon was fully lit, toward the day side
of twilight. Once the stars became bright, the horizon would darken and
become a thick band. The best plan was to sight while the stars were just
showing, bring the star to the sharp horizon, swing the star (rock the
sextant), and lay the star on the horizon. Many times, especially with a high
star, the star would disappear on or near the well-lit horizon.
The sky just above the horizon is lighter than the rest of the sky and the
swinging takes away some of the concentration needed to stay locked onto the
faint star or the pale disk of a planet. In order to sit that faint star on
the distinct horizon, I experimented with bringing the faint star into the
relatively darker water and rocking the sextant, watching the star enter and
leave (in and out) the water.
I found that I could quickly isolate the exact point under the star ?Vertical
Sextant,? be it high or low. I could concentrate on putting the star on the
horizon by halving the ?in and out? mentally and bringing the star above that
point on the horizon and then coming down for the mark. It worked so well for
me that I started using the same procedure for the sun and bright stars. Very
accurate fixes were easy.
I admit that my celestial fixes were not so accurate after a transfer to duty
with less demanding celestial navigation practice. When I shifted back to
?Vertical Sextant? (in and out of the water), my fixes would improve and
tighten with no random near misses. Give the technique a good try.
Byron Franklin
Newport, Rhode Island.

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