USCG Exam PracticeSingle-screw maneuvering and prop walk
During a compound maneuver on a single-screw vessel, a short burst of ahead power is applied while the rudder is held over. What is the PRIMARY effect that makes this useful for controlling the stern's position?
- ✓ The discharge current directed across the shifted rudder, combined with propeller side force, walks the stern back toward the desired sideCorrect
- B. The suction screw current draws the stern toward the rudder, counteracting the backing side force
- C. Increased shaft RPM reduces cavitation and restores rudder effectiveness during the astern phase
- D. The ahead burst kills sternway, allowing the pivot point to shift forward and increase rudder leverage
Why A is correct
A short burst ahead uses propeller side force and the discharge current directed across the shifted rudder to walk the stern back the other way. The manual cautions to use no more power than needed so sternway is not killed and a worsening discharge current is not created.