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                                                Compass Error Licked,
Byron Franklin, page 1.

                                                        The Franklin
Piloting Technique
            Compass Error Licked.

In 1958 I reported aboard the USS Outpost AGR 10. The AGR was a radar
picket ship modified from a World War II Liberty Hull. She was very
top heavy with high radar antennas and the same gyro she was
originally built with. Her mission was to track any thing heading
toward the United States and report anything that was unscheduled.  A
jet fighter plane from the main land would investigate the intruder.
Accurate navigation was important to ensure we were on station, using
the gyro, Loran A and the sextant. The old gyro was good enough to run
the open sea, but was always slow moving about the meridian, so that
visual cross bearings in restricted water were difficult. As the
quartermaster chart plotter I could give good navigation
recommendations to Officer of the deck (OOD), but I was not happy with
the charted fixes that my recommendations were based on. I had noticed
that when coming into the last leg and heading north to our pier,
there were two charted well-spread Navigation Aids (Navaids) close by
to port-side. Also, the ship was visually in the middle of a north/
south channel with buoys on both sides. IT WAS EASY TO SEE THAT WE
WERE IN THE CENTER OF THE CHANNEL. The third and only other Navaid was
to the south and far away. The line of position (LOP) from the well
spread close by (<2000yds) Navaids always crossed in the center of the
channel where we were visually between the buoys. The only other
Navaid was far to the south (> 6000yds), This Navaid�s LOP was always
outside of the 100 yards wide channel.
The AGR moored, I was tired after the two months at sea and piloting
the AGR for about the two-hour transit to pier-side. I boarded a buss
to go home, Newport RI. The compass error problem would not let me
rest, so I went over in my mind, the two close-by charted fixes always
in the channel and the far Navaid falling outside of the channel.
It became apparent! An idea that I could use the close by well-spread
Navaids to get my fix.
 I needed a third LOP to make the fix legal (according to the book,
three LOP�s) so I can correct each of the LOP�s by using the bearing
of the far Navaid as true from the center of the buoyed channel �FIX�,
the observe sighted bearing difference was error, I could use the same
correction for all three, collapsing the triangle.  I found that I
could use this technique anytime to find and maintain a fix, while
monitoring the movement of the compass. Once underway, I no longer
needed the buoyed channel as a guild and I could use the far LOP to
give me both direction and amount, any time or place to correct the
compass.
With this idea I tamed the monster of compass error. It became a pussy
cat to me.
            My complete mechanics to Cross Bearings �The Franklin
piloting Technique.�




By the book and classroom teaching, when a triangle is plotted, pick
the center as the fix. This rule leads to failure. When three Navaid
are plotted within 180 degree you are not in the triangle. You are
outside, the two closer is the fix and the farther is your indicator,
accuracy and compass error for a correction. Publishers don�t try new
ideas they just repeat what has already been in other books.




                                                   Compass Error
Licked, Byron Franklin, page 2.

                                                    Mechanics to Cross
Bearings
                                                    Geometry of
Piloting
The chart plotter and navigator should have a complete knowledge of
plotting geometry to insure accurate fixes. Plotting geometry is
predictable, uncomplicated and easy to use once understood.
                                                          Geometry
Special knowledge.
 A. single line of position (LOP) has two (two) dependable predicable
traits (1) direction (2) offset
    1 Direction. When facing each NAVAID.
         a. When compass error is present, each line of position (LOP)
will miss the observer to the left hand when the error is WEST and to
the Right when the error is EAST.  See figure1
     2. Offset. When facing each Navaid, the line of position (LOP)
will offset distance of the closest point of approach (CPA.)at the
observer                                                        See
figure2.
        a. When compass error is present, the (offset) CPA distance
will depend on the distance to each Navaid and the amount of gyro/
compass error in degrees.
         b. Close Navaids will have a closer (offset) LOP to the
observer, far Navaids will have a farther CPA. The offset can be, but
not needed) computed by using the rule of sixty (Radian rule)
B. LOP�s will have either (1) systematic error or (2) a random error
       1. Systematic error is, the true angle between the LOP�s is
correct, but the true north ailment is off the meridian. This may be a
gyro, bad repeater alignment or seeking the meridian.
        2. Random error is, the true angle between the LOP�s is not
correct and may be caused by bad observation, ship movement between
observations or compass card not centered.
The magnetic compass with the problems of ship movement is normally
random.
         3. Any two Navaid LOP�s that are systematic will cross
somewhere on a circle that includes the observer position. If a third
Navaid on the circle and its LOP are added, all LOP�s will cross at
the observers position on the circle, but the three, if in systematic
error will fall on the circle to the west (left hand) or to the east
(right hand)of the observer the greater the error the greater the
distance.    -Still intersecting on the
circle-.                                        See figure
3.                         4. Navaids LOP�s that are random will work
in the same manner but will be not be as accurate. The Franklin
Piloting technique will improve fixes with Random error such as the
magnetic compass. (with or without variation or deviation.)
See Franklin piloting Technique.
          5. Any combination of Navaids will work with the Franklin
technique except the case where all three Navaids are on a circle with
the observer. This is easy to recognize on the chart and a rare
happening. In this case the center Navaid would be the
farthest            revisit Figure 3.
The far Navaid can give near 100% total compass error when not between
the fixing navaids
it will give less than total. When the far Navaid is opposite the
fixing Navaids the far Navaid will give more than total
error.                       See figure 4.

I will have to send figures later.

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