Which two axes use CCDA?

• A. Thrust and pitch
• B. Yaw and roll
• C. Pitch and yaw
• D. Thrust and yaw

Answer: (A)

Focus on how CCDA affects motion in a rotorcraft. CCDA relates to the two axes that drive forward movement and nose attitude: the thrust axis (forward motion along the body’s forward direction) and the pitch axis (rotation that tilts the nose up or down about the lateral axis). When the rotor disc is tilted forward with the cyclic, a forward component of thrust is produced, which changes speed along the thrust axis and also changes the aircraft’s pitch attitude. The other axes, like yaw (turning left/right about the vertical axis) and roll (tilting side to side about the forward axis), are controlled by different inputs and aren’t the pair linked by CCDA. So the combination that CCDA uses is thrust and pitch.