What is the primary function of a propeller governor?

The primary function of a propeller governor is to control the propeller blade angle to maintain a desired engine RPM. This is crucial for ensuring that the engine operates efficiently and within its designed RPM range. The governor automatically adjusts the pitch of the propeller blades in response to changes in engine speed and power settings, allowing for optimal performance across various flight conditions.

By altering the blade angle, the propeller governor influences the amount of thrust produced by the propeller while ensuring that the engine remains within safe operational limits. This mechanism is especially important in variable-pitch propellers used in many aircraft, as it allows for better climb performance, fuel efficiency, and overall aircraft handling.

In contrast, increasing engine RPM at all times would not only be inefficient but potentially hazardous to engine health. Reducing fuel consumption during flight is a secondary effect of managing RPM effectively but is not the direct function of the governor itself. Preventing engine overheating relates to engine management but is not a duty of the propeller governor. The governor's role focuses specifically on maintaining the appropriate blade angle for the desired engine speed, which supports overall optimal aircraft performance.