Chart Correction Techniques
After a little practice on obsolete charts, corrections to printed
information on nautical charts can be made neatly and quickly. These
corrections become a permanent part of the chart and may involve the
safety of the ship. Corrections must be made in ink so they will not be
accidentally erased when you are cleaning the chart after use. The only
instruments necessary to correct charts are several high-quality ball-point
pens or central feed technical fountain pens, a variety of stick or
pencil-type erasers, and typographical correction fluid.
Example: The NTM states that you are to add a buoy at 25°10'33"N
70°21'12"W. Locate the coordinates on the chart, determine if you need
to erase part of the chart to insert the buoy. If necessary erase or use
typing correction fluid (white out). NOTE: Any information that is
removed from a chart must be redrawn after the correction is made.
This calls for the person effecting the correction to use some degree of
Use the chart correction template (fig. 1-22, available from DMAHTC)
to draw the buoy on the chart. Write in any information about the buoy.
Chart correction may be completed in many ways. It is wise to
purchase additional templates from local sources that carry drafting
supplies. As a rule, corrections must always be neat and legible. Never
use red ink to make corrections to a chart. The Navy uses red lighting
at night. Red ink will disappear under red lights, making the correction
invisible and putting the ship at risk. DO NOT USE RED INK!