What aspect of the propeller affects overall boat stability?

The rake of the blades is an essential aspect of a propeller that can significantly influence a boat's stability. Rake refers to the angle at which the blades are positioned relative to the vertical axis of the propeller hub. This angle affects the thrust and the way the water is displaced by the propeller.

When the rake of the blades is designed appropriately, it helps to optimize the boat's lift and thrust. This balance can improve the overall stability by allowing the boat to maintain a desired attitude and reduce the tendency to pitch or roll. A propeller with well-tuned rake can enhance performance, particularly in terms of maneuverability and handling, while also affecting the way the boat interacts with waves and water currents.

In contrast, while other elements such as the weight of the engine, diameter of the propeller, and shape of the hull play roles in a boat's performance, they do not directly correlate with how the rake impacts stability in terms of hydrodynamics and control during operation.