What component controls the propeller pitch in the T-6 aircraft?

The propeller pitch in the T-6 aircraft is controlled by the propeller interface unit (PIU). The PIU is an essential component that manages the blade angle of the propeller, enabling adjustments to optimize performance across various phases of flight. It operates automatically to maintain the desired RPM and ensures efficient propulsion by altering the pitch of the propeller blades, allowing for both increased thrust during takeoff and landing, as well as optimized fuel efficiency during cruise.

The mechanical pitch control unit is not the main component for pitch control in this aircraft as the T-6 utilizes a more advanced system. The electronic flight control system primarily focuses on the aircraft's overall flight characteristics and stability rather than directly controlling propeller pitch. The throttle control module manages engine power rather than pitch, making it critical for thrust management but not for pitch adjustments. Thus, the identification of the propeller interface unit as the correct answer stems from its dedicated function in controlling propeller pitch effectively.