Navigation General · Sailings — Great Circle vs Rhumb Line
Between two points not on the equator or the same meridian, the great-circle track compared with the rhumb-line track is:
- AShorter, but the course continuously changes✓ Correct
- BAlways longer
- CIdentical in length
- DOnly usable by sail vessels
Explanation
The great circle is the shortest distance but crosses successive meridians at changing angles, so the course must be adjusted along the way. The rhumb line holds a constant course (a straight line on a Mercator chart) but is longer.
Authority: Bowditch
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