Chart Navigation & Plotting · Speed-Time-Distance — Speed from Run
You log 36 NM between a 1000 fix and a 1230 fix. What was your speed over the ground?
- A16.0 knots
- B12.0 knots
- C14.4 knots✓ Correct
- D18.0 knots
Explanation
Elapsed time is 2.5 hours (1000 to 1230). Speed = distance ÷ time = 36 NM ÷ 2.5 h = 14.4 knots over the ground.
Authority: Bowditch (Pub. No. 9), Speed-Time-Distance
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