Chart Navigation & Plotting · Piloting — Horizontal Danger Angle
To stay outside a charted danger using a horizontal danger angle measured between two charted objects, the navigator keeps the measured angle:
- AGreater than the danger angle
- BLess than the danger angle (a larger angle means you are too close)✓ Correct
- CExactly at the danger angle
- DAt 90° at all times
Explanation
The horizontal danger angle is the angle subtended by two charted objects from the circle tangent to the danger. The closer you are, the larger the angle, so keeping the measured horizontal angle LESS than the danger angle ensures you remain outside the danger circle.
Authority: Bowditch (Pub. No. 9), Danger Angles
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