Chart Navigation & Plotting · Plotting Conventions — Labeling
By convention, a course line on a chart is labeled with the course above the line and the speed below it, using:
- AMagnetic course only, never true
- BCourse below the line and speed above it
- CThree digits for course (e.g., C 090) and 'S' with the speed (e.g., S 12)✓ Correct
- DDistance above the line and time below it
Explanation
A course line carries 'C' followed by the three-digit course above the line and 'S' followed by the speed below it. A fix is labeled with the time in four digits; a DR is a semicircle with the time; an EP is a square. Consistent labeling lets any navigator interpret the plot.
Authority: Bowditch (Pub. No. 9), Labeling the Plot
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