General Subjects (Auxiliaries & Systems) USCG Question #851 (Set 13)

What is meant by the term "left-handed" propeller?

Official USCG Answer & Rule Citation

Correct Answer: Option D — A "left-handed" propeller is a propeller which rotates in the counter-clockwise direction when viewed from astern.

Propeller hand is determined by the direction of rotation when viewed from astern looking forward. A left-handed propeller rotates counter-clockwise. This standard nomenclature is critical for understanding torque effects and vessel handling characteristics during maneuvering, particularly when operating twin-screw vessels with counter-rotating propellers.

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