What is required for the rudder to effectively steer a boat?

For a rudder to effectively steer a boat, it is essential to have flow over the rudder. The rudder works by directing water flow, which creates a difference in pressure on either side of the rudder surface. When the boat is in motion, water moves around the rudder, allowing it to respond to the steering commands given by the helmsman. This flow creates lift on the rudder, enabling it to pivot and change the direction of the boat.

Without adequate flow, the rudder cannot generate the necessary force to effectively steer the vessel, resulting in poor maneuverability. High speed can enhance rudder performance, but it's not the fundamental requirement; flow is what allows the rudder to function as intended. Proper weight distribution and clear weather conditions are beneficial for overall stability and safety but do not directly relate to the fundamental operation of the rudder in steering.