Navigation General · Charts — Gnomonic Projection
On a gnomonic chart, a great circle is represented as:
- AA curved line
- BIt cannot be shown
- CA circle
- DA straight line✓ Correct
Explanation
The gnomonic projection shows great circles as straight lines, which is why great-circle sailing routes are first laid out on a gnomonic chart, then transferred as a series of points/rhumb-line legs onto a Mercator chart for steering.
Authority: Bowditch
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