In what situation are cable tension and control surface effectiveness directly related?

Cable tension and control surface effectiveness are directly related when the control surfaces are deflected. This relationship is crucial because the effectiveness of control surfaces, such as ailerons, elevators, and rudders, depends on the deflection angle, which in turn affects the aerodynamic forces acting on the aircraft.

When a control surface is deflected, the cable connected to that surface must maintain sufficient tension to ensure it moves accurately and does not encounter any slack. Proper cable tension contributes to the responsiveness of the control surfaces, allowing pilots to achieve the desired control inputs effectively. If the cable tension is inadequate, the movement of the control surface may be compromised, leading to a decrease in effectiveness, which is critical for the aircraft's control and stability during flight.

In contrast, during takeoff, in a descent, or during level flight, while cable tension is important, the direct relationship between the tension in the cables and the effectiveness of the control surfaces is most pronounced when the control surfaces are being actively deflected. This is because the aerodynamic forces are engaged at that moment, making it essential for the cable system to be properly tensioned to maintain the desired performance of the aircraft.