Chart Navigation & Plotting · Set & Drift — Estimated Position
From your 1200 DR, a current is known to set 180°T at 2.0 knots. Where is the 1400 estimated position relative to the 1400 DR?
- A4.0 NM due east of the 1400 DR
- B4.0 NM due north of the 1400 DR
- C2.0 NM due south of the 1400 DR
- D4.0 NM due south of the 1400 DR✓ Correct
Explanation
An estimated position is the DR adjusted for current. Set 180°T (due south) at 2.0 kt for 2 hours displaces the vessel 4.0 NM to the south. The EP therefore lies 4.0 NM due south of the 1400 DR.
Authority: Bowditch (Pub. No. 9), Estimated Position
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