You are turning 68 RPM, with a propeller pitch of 18 feet, and an estimated slip of +2%. What is the speed of advance?
Official USCG Answer & Rule Citation
Correct Answer: Option D — 11.8 knots
Apply the speed of advance formula: Speed = ((RPM * Pitch * 60) / 6080) * (1 - Slip). With 68 RPM, 18 feet pitch, and 2% slip (0.98), the calculation (68 * 18 * 60 / 6080) * 0.98 equals 11.8 knots. This formula is essential for accurate dead reckoning and voyage planning.
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