Propellers

Proper propeller servicing and overhaul help ensure safe operation, reliable performance, and maximum service life. This section covers cleaning, lubrication, air dome charging, overhaul, and propeller reassembly procedures. Servicing Propellers Propeller servicing includes cleaning, lubricating, and replenishing the operating lubrication supply. Cleaning Propeller Blades Aluminum and steel propeller blades and hubs are usually cleaned by … Read more

Aircraft propellers can be classified according to their position relative to the engine and airframe. The two primary configurations are tractor and pusher propellers. Each arrangement affects airflow, efficiency, maintenance requirements, and susceptibility to foreign object damage. Tractor Propeller Tractor propellers are those mounted on the upstream end of a drive shaft in front of … Read more

Proper propeller maintenance is essential for minimizing vibration, ensuring efficient engine performance, and extending propeller service life. Excessive vibration can result from propeller imbalance, improper blade tracking, or incorrect blade angle settings, increasing stress on the engine and airframe. Routine inspection and adjustment help maintain smooth operation, improve aircraft reliability, and reduce the risk of … Read more

Proper propeller removal and installation are essential to ensure safe operation, correct alignment, and reliable performance. Following approved maintenance procedures helps prevent damage to the propeller and engine components while maintaining proper mounting integrity. This section outlines the general procedures for removing and installing a propeller assembly. Removal The following procedure is provided for demonstration … Read more

An increasing number of light aircraft are designed for operation with governor-regulated, constant-speed propellers. However, many general aviation aircraft still operate with fixed-pitch propellers. Light-sport aircraft (LSA) commonly use multiblade fixed-pitch composite propellers, while many medium-size turboprop aircraft are equipped with reversible-pitch propeller systems. Larger transport and cargo turboprop aircraft typically use propeller systems with … Read more

A propeller governor is an engine RPM-sensing device and high-pressure oil pump that automatically maintains the selected propeller RPM in a constant-speed propeller system. It responds to changes in engine RPM by directing pressurized oil to the propeller hydraulic cylinder or releasing oil from it. The resulting change in oil volume adjusts the blade angle, … Read more

The Pratt & Whitney PT6 Hartzell propeller system is a hydraulically operated, constant-speed propeller designed to provide efficient thrust and reliable performance throughout all phases of flight. This article explains the construction, operation, and control of the PT6 Hartzell propeller system, including constant-speed governing, beta and reverse operation, feathering, overspeed protection, and autofeather functions. The … Read more

Propeller auxiliary systems improve the safety, reliability, and operational efficiency of aircraft propellers in various flight conditions. These systems include ice control, synchronization and synchrophasing, and autofeathering mechanisms that help maintain propeller performance, reduce vibration, and enhance aircraft controllability. This article explains the purpose and operation of these essential propeller auxiliary systems. Ice Control Systems … Read more

Constant-speed propellers automatically adjust blade pitch to maintain a selected engine rpm despite changes in airspeed, power setting, or flight conditions. They improve aircraft performance, efficiency, and engine operation compared to fixed-pitch propellers. This article explains the construction and operation of Hartzell constant-speed nonfeathering and feathering propellers, as well as the methods used for feathering … Read more