What defines propeller torque?

The correct definition of propeller torque refers to the turning moment produced by the propeller about the axis of the crankshaft. This torque is a crucial concept in understanding how a propeller interacts with the engine and the overall aircraft performance.

Propeller torque occurs when the blades of the propeller generate a rotational force as they move through the air. This force produces a moment around the crankshaft, causing the engine to experience a rotational effect. This moment is important because it is directly related to the engine's output and contributes to the overall efficiency of the propulsion system. When the propeller rotates, it creates a resistance against the engine's crankshaft, which can impact the power needed from the engine to maintain or increase thrust.

The other options focus on different aspects of propeller dynamics. For instance, the tendency of the propeller to twist around its longitudinal axis pertains more to structural aspects of the propeller itself rather than its functional contribution to torque. The helical path of the propeller through the air describes its operational movement, while the thrust produced by the propeller is a result of aerodynamic forces acting on the blades but not directly indicative of torque. Understanding that propeller torque specifically addresses the moment produced around the crankshaft allows us to appreciate its