Chart Navigation & Plotting · Distance Off — Doubling the Angle
A landmark bears 20° on the bow, later 40° on the bow; you ran 6.0 NM between. Your distance from the landmark at the second bearing is:
- A3.0 NM
- B6.0 NM✓ Correct
- C12.0 NM
- D8.5 NM
Explanation
Doubling the bow angle (20° then 40°) makes an isosceles triangle, so the distance off at the second bearing equals the run between bearings: 6.0 NM.
Authority: Bowditch (Pub. No. 9), Distance by Two Bearings
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