What component adjusts the engine oil pressure to control propeller RPM?

The propeller governor is responsible for adjusting engine oil pressure to control propeller RPM. It operates by using oil pressure to manipulate the propeller blades' angle in response to changes in engine performance and pilot inputs. By maintaining the desired RPM, the prop governor ensures that the propeller operates efficiently and effectively across different flight conditions.

The prop governor detects changes in the rotational speed of the propeller and adjusts the oil flow accordingly to increase or decrease the pitch of the blades. If the RPM rises above a preset value, the governor increases the blade angle, creating more drag and reducing RPM. Conversely, if the RPM falls below the set point, the governor decreases the blade angle, allowing the propeller to turn faster. Hence, the prop governor plays a critical role in regulating engine output and overall aircraft performance.

The other options do have roles in engine operation but do not fulfill the specific function of controlling the propeller RPM through oil pressure adjustment. The oil pump is necessary for circulating oil but does not directly control the propeller's speed. The fuel control unit regulates fuel flow to the engine while the engine management system oversees various engine parameters but does not specifically handle propeller RPM control via oil pressure adjustments.