Chart Navigation & Plotting · Sailings
Composite sailing is used when a great-circle track would:
- ACross the equator
- BCarry the vessel into higher latitudes than is safe or desirable (e.g., into ice)✓ Correct
- CBe longer than the rhumb line
- DRequire a gnomonic chart
Explanation
Composite sailing limits the highest latitude reached: the track follows a great circle to a chosen limiting parallel, runs along that parallel, then follows another great circle to the destination — keeping the vessel clear of ice or heavy weather while still minimizing distance.
Authority: Bowditch, American Practical Navigator (Pub. 9), composite sailing
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