Navigation and Seamanship

1.3.3.4. Principle rules for labeling DR plots

1.3.3.4. The principle rules for labeling DR plots are as follows

The DR line – direction and speed along a course line should be written along that line.

Direction – C – indicating the true course in degrees (3 digits) – should be placed above the course line.

Speed – S – knots labeled below the course line

Symbol for a fix is a small circle surrounding a small dot, and the time is written horizontally close nearby.

Half circle with dot on a straight segment of a course line.

Semi circle without dot – change of direction.

A DR position shall normally be plotted every hour

A DR position shall be plotted of the time of every course change

A DR position shall be plotted at the time of every speed change