In a constant-speed propeller installation, which statement best describes the function of the propeller control?

• A. Regulates a variable blade angle
• B. Regulates a constant blade angle
• C. Maintains constant torque
• D. Adjusts RPM to maintain speed

Answer: (B)

In a constant-speed propeller system, the propeller control sets the target engine RPM, and the governor automatically changes the blade pitch to hold that RPM. Because engine load and airspeed change during flight, the blade angle must vary to keep the RPM steady. So the function is to regulate a variable blade angle to maintain the selected RPM. The pitch is adjusted up or down as needed to hold speed, rather than keeping the blade angle fixed. This system isn’t about keeping torque constant, and it doesn’t directly set RPM to maintain airspeed—the pilot sets the RPM target, and the governor maintains it by varying pitch.