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The Fix
Navigating, or
finding your way at sea, can be fairly simple
or very complicated. It all depends on
what you are navigating, where you are, and what aids there are for you
to
use. I’ll give some examples. Back in the
1960s, navigating a small sailboat of 24 feet
off the coast of At night, the
job was still fairly simple. It got
interesting once you sailed south of The only
navigating aid on that part of the Mexican coast
was Only a little over twenty years ago I got to
go fishing in
the We left St.
Marks on a heading just east of due south. He
never looked at a chart. He just ran out
on a compass heading until
the fathometer told him the bottom was at the 40 foot depth level. He then stopped to fish for a bit. He then turned the boat to the southeast to
follow the 40 foot depth curve. At the end of
the day he headed back to shore on a different
heading. After a while the St. Marks
lighthouse came into sight. All without
referring to a chart. He really knew the
waters in that area. This whole coast of
the Almost twenty
years later, I went fishing with my friend Every time we
went fishing, I gave One man I know
seemed foolish to me. He used to go out
thirty miles to fish using
only his GPS. He didn’t even have a
compass on his boat, much less a chart. Needless
to say, I never asked to go fishing with him. He
never thought of the possibility of the
batteries going dead in that GPS unit. All this has
been small boat fishing. Large naval
vessels are a different
story. I went to officer training in the
late 1960s. That was after my Modern Navy
ships these days all use satellite navigation,
which is GPS (Global Positioning System). Back
in my Navy days, in the late 1960s and early 1970s,
this was akin
to Star Wars technology, not even imaginable. What
I have to relate deals with the good old days…..
before GPS. Finding your
way along a coast using landmarks is called
piloting. I did all right in that class
in officer’s school. Real navigating
involved the use of a LORAN, which uses radio signals that form an
invisible
criss-cross across areas of the ocean, or celestial navigation. LORAN uses a
receiver much like a radio and is fairly
accurate. Unfortunately, it did not
cover all areas of the oceans. It was
also subject to interpretation. That is
fine if you are far at sea and were not in danger of grounding. Celestial
Navigation uses the stars to find your way. It
has been around for a few hundred
years. We’re talking the about the tools
that I could use a
LORAN in a classroom situation fairly
well. Celestial navigation was almost
impossible for me to get good at while I was in school.
All the practice problems I did were to no
avail. I always plotted my imaginary
ship on some mountaintop. Fortunately my
failure at celestial navigation did not prevent me from becoming a
naval
officer. It seems all Navy ships have
one officer who is assigned as a Navigator. At sea, when I
came on the bridge to relieve the Officer of
the Deck (OOD), I checked the chart. On
it was plotted the ship’s course, as laid out by the ship’s navigator. Unless there were instructions to the
contrary, I stayed on that course. Every
half-hour I marked where I estimated the ship’s position to be. That is called “dead reckoning”, or a DR
plot. If the ship was
out of LORAN range, the ship only gets a
good fix just before and after sunrise when the navigator and one of
his
quartermasters “shot” the stars with a sextant. The
same instrument that My first ship
was up the Mekong Delta in My second ship
was a minesweeper. I did get to conn the
ship a lot, but I was
just a spectator when we were out of sight of land or out of range of
radar. Out that far, the navigator did
all the navigating. My third ship
was the large fleet oiler. We were at sea
a lot. When I was OOD, I usually had a
junior
lieutenant or an even more junior ensign standing watch under my
supervision. I usually had the same
officer standing watch
with me every day. They were designated
as the Junior Officer of the Watch, or “JOOD”. Some
OODs kept the conn all the time they were on watch.
They wanted absolute control of the ship.
I preferred to give the conn to the junior
lieutenant. This had one
side effect. One ensign on our ship came
to me with a problem. His OOD never gave
him the conn. He said he would never
qualify as Officer of
the Deck if he were never given the conn. He
had talked with my JOOD and learned that I gave him all
the ship
handling experience he wanted. He wanted
me to go to the captain and get him changed to my watch.
I did this and he did qualify as OOD before I
left the ship. As Officer of
the Deck, I was still responsible for the ship
in the absence of the captain from the bridge, even if I gave the conn,
or
control to a junior officer. Basically,
I made sure that he ran the ship under my supervision.
As the JOOD became more experienced, I did
not interfere with his running the ship. At
least as far as orders to the helmsman and the engine
orders. A JOOD who was
becoming proficient in his job would report
any ships that appeared, either visually, or on radar.
He would then explain if they would interfere
with our passage and what he thought we should do as far as a course
change. This was to ensure all ships
passed safely. I mention all
this, because as I trained my junior officers
they became more proficient. I had
less
to do and became more of a spectator. Don’t
get me wrong, I was proud of my JOODs. The
problem was that I was bored on a long
passage. There was no land in sight for
days or weeks and the ship sailed mostly on a straight course.
That was the
easy part. The part of navigating that
scared me was the books. There was the
Nautical Almanac, and HO
214. HO 214 is a book of nothing but
columns of numbers, from cover to cover. My first sun
line, one observation, took me twenty minutes
to solve. I was proud of myself. Within a few days I could do three
observations in five minutes. When the
captain would come to the bridge he would automatically look at the
chart. All of a sudden there were
pencilled notes on
the chart saying “LOP,” or “line of position.” He
never asked me about the sun lines. All he
knew was that whoever made those notes (the present
OOD) knew a
little more about the ship’s position than the other OODs who did not
do this. I think the
navigator was a bit put off by my progress. He
knew that I was doing my sightings without
any help from his quartermasters. If I
was on watch at “star time” I shot my stars even if he and his
quartermaster
were shooting theirs. My four-hour
watches on the bridge were boring no
longer. Every half-hour I shot a sun
line and marked it on the chart. If I
was going to be on the bridge during the hours when it is possible to
shoot
stars and get a good fix, I had to make preparations.
That required research. First
I had to find the hour angle. I won’t
bother you with details, but it
involved knowing how many degrees from I was always
amazed to find those stars about where the
books said they would be. Once I took a
sight with the sextant, I would know exactly where the ship was, based
on the
tables in the books. I got where I could
shoot three stars, do the math, and plot our position, within five
minutes. Well before the navigator was
finished. My duties as
Officer of the Deck did not suffer. I had
one of the best trained JOODs on the
ship. After all, I trained him. Knowing how to take a fix gave me an inner
feeling of self confidence. One night the
ship was sailing to the southeast from the Some time that
night, we sailed out from under the cloud
cover. I was on watch as OOD at the
time. It was a very unusual night. There was a brilliant moon and there seemed
to be a distinct horizon. I knew that
any horizon in moonlight was not supposed to be accurate, but if I got
three
stars to cross at one point, I was certain it would be a good fix. I scrambled to
look up the stars to shoot for the hour at
hand. I picked my stars and got my
sextant. I got three good
sightings. When I worked out the problem
I had a perfect three star fix. It was
the first good fix in two days. I called
the captain and informed him that I had a fix. He
came to the bridge and looked at the chart.
Tom Sparkman October
20 , 2002
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