USCG Exam PracticePlot true course and distance between two charted points
After drawing a course line between two charted points, you walk parallel rulers to the nearest compass rose to read the true course. From which ring of the compass rose is the true course read?
- A. The inner ring, which is graduated in magnetic degrees
- ✓ The outer ring, which is graduated in true degreesCorrect
- C. Either ring, since both are referenced to true north on US charts
- D. The middle ring, which corrects for local variation
Why B is correct
The true course is read where the parallel rulers cross the outer (true) ring of the compass rose. The inner ring is the magnetic ring and must not be used when determining true course. (Bowditch Ch. 4 §406)
Cited:Bowditch Ch. 4 §406