USCG Exam PracticeSingle-screw maneuvering and prop walk
When backing a single-screw vessel, the recommended initial helm action BEFORE engaging astern is to:
- A. Hold the rudder amidships to minimize drag and allow sternway to develop before correcting
- B. Apply full rudder toward the side the stern is expected to swing toward, to amplify the turn
- ✓ Apply full rudder toward the side that opposes the expected propeller side force swingCorrect
- D. Apply half rudder away from the expected swing and increase to full rudder once sternway builds
Why C is correct
USCG Boat Crew Seamanship Manual §10-C specifies that the workable sequence begins with applying full rudder toward the side that opposes the expected swing before starting astern. The rudder has little effect until sternway exists, but pre-positioning it maximizes its corrective force as sternway develops.