Which of the following parameters is NOT used by the TAD to compute the desired rudder trim tab position?

The desired rudder trim tab position in the T-6A is computed by the Trim Aided Directional (TAD) system using several dynamic flight parameters, including engine torque, airspeed, and pitch rate. Each of these parameters plays a crucial role in determining how much trim is needed to maintain coordinated flight under varying conditions.

Engine torque, which results from the asymmetrical thrust produced by the propeller, influences the need for rudder input to counteract yaw. Airspeed affects aerodynamic forces and the effectiveness of the rudder, while pitch rate indicates how quickly the aircraft is changing its pitch orientation, which can also influence the yaw dynamics.

In contrast, wing load is not directly involved in the computation of rudder trim tab position. While wing load can impact overall aircraft handling and performance, it does not provide the TAD system with specific information regarding the yaw behavior or trim requirements. Therefore, it is not a parameter used by the TAD for calculating the desired rudder trim position.