USCG Exam PracticeSingle-screw maneuvering and prop walk
When going ahead with the rudder amidships, the vessel holds a straight track. Which of the following best explains why putting the rudder over causes the bow to swing in the OPPOSITE direction to the stern?
- A. Increased rudder angle reduces propeller side force on the stern, allowing the bow to swing freely
- B. The suction screw current draws the bow toward the side opposite the rudder deflection
- C. The discharge current acts on the bow thruster, pushing the bow away from the rudder angle
- ✓ The rudder force pushes the stern to one side, and because the vessel turns about its pivot point, the bow swings the opposite wayCorrect
Why D is correct
When the rudder is put over, the resulting pressure differential pushes the stern to one side. Because the vessel rotates about its pivot point, the bow swings in the opposite direction to the stern. This is a fundamental principle of rudder action described in §10-B.