🔍 Key Concepts

• Transverse thrust (propeller walk) on a single-screw vessel • Effect of ahead vs. astern power on sideways movement of the stern • Difference between rudder effectiveness and propeller side force

💭 Think About

• When does the propeller wash flow strongest across the hull and cause the stern to "walk" sideways the most? • Does transverse thrust become more noticeable when you have strong ahead movement, or when you have little forward motion but high propeller RPM? • In which condition is the rudder least effective, making the sideways push from the propeller the dominant effect?

✅ Before You Answer

• Identify when water flow over the rudder is low, so the rudder can’t easily counteract prop walk • Consider which engine command gives high propeller thrust but minimal ahead speed • Think about typical harbor maneuvering: when do operators most notice the stern kicking sideways on a single-screw boat?