Which option is NOT listed as a method to move the PGM control surfaces?

• A. Hydraulic
• B. Pneumatic
• C. Electric Motors
• D. Electro-Servo Actuators

Answer: (C)

Actuation of PGM control surfaces relies on fluid power or integrated electromechanical actuators rather than simple electric motors. Hydraulic and pneumatic systems provide the high force and reliable motion needed to move control surfaces, using fluid pressure to produce the necessary movement. Electro-servo actuators combine an electric drive with servo-controlled output (often incorporating hydraulic or mechanical elements) to achieve precise positioning and feedback. A plain electric motor by itself isn’t used as a stand-alone method for moving these surfaces in this context, because it lacks the integrated feedback and power orchestration provided by hydraulic/pneumatic systems or electro-servo units. Therefore, electric motors are not listed as the method, while hydraulic, pneumatic, and electro-servo actuators are.