USCG Exam PracticePlot true course and distance between two charted points
A vessel is at latitude 35°N and the navigator measures a course line with dividers set to 30 minutes of arc on the latitude scale at 35°N. What distance does this represent?
- A. 30 statute miles
- B. 60 nautical miles
- ✓ 30 nautical milesCorrect
- D. 15 nautical miles
Why C is correct
One minute of latitude equals one nautical mile. Therefore 30 minutes of latitude measured on the latitude scale at the working latitude equals 30 nautical miles. Bowditch Ch. 4 §405 and §406 establish this equivalence and the requirement to measure at the working latitude.