Chart Navigation & Plotting · Sailings
A great-circle route is generally preferred over a rhumb-line route on long ocean passages because it:
- AIs the shortest distance between two points on the Earth✓ Correct
- BMaintains a constant course
- CAvoids all currents
- DIs easier to plot on a Mercator chart
Explanation
A great circle is the shortest path between two points on a sphere, saving distance on long, high-latitude runs. The trade-off is a continuously changing course, so the track is broken into rhumb-line legs between waypoints.
Authority: Bowditch, American Practical Navigator (Pub. 9), great-circle sailing
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