17.2.5 Propeller Installation Flashcards
What is required for an engine to transmit rotation and torque to a propeller?
The propeller must be attached via the hub to a suitably designed propeller drive shaft.
What are the common types of propeller drive shafts?
The most common types are Tapered Shaft, Splined Shaft, and Flanged Shaft.
What is a Tapered Shaft?
Tapered shaft drives are usually found on small, older, low-powered piston engines.
How is a propeller secured to a Tapered Shaft?
The propeller is secured to the engine shaft with a retaining nut that screws onto the engine shaft and presses the tapers together.
What is the purpose of the key in a Tapered Shaft installation?
The drive is transmitted through a key that is seated in slots machined in both the engine shaft and the propeller hub.
What characterizes a Splined Shaft?
The propeller shaft of high-output radial engines is generally splined and threaded on one end for a propeller hub nut.
How are splined shafts identified?
The sizes of splined shafts are identified by an SAE number.
What is the purpose of the master spline in a Splined Shaft?
This ensures that the propeller is installed in only one position relative to the shaft for synchronising and/or synchrophasing.
What is a Flanged Shaft?
Flanged propeller shafts are used on most modern reciprocating and turboprop engines.
What is the method of propeller installation dependent on?
The method of installation depends on the type of propeller and the appropriate maintenance manual must be carefully followed.
What should be done before fitting the propeller to a splined drive shaft?
Remove all protective covers and plugs and clean parts which have been covered with a protective coating.
What should be checked after propeller installation?
The blade track should be checked to the tolerances specified by the manufacturer’s specifications.
What is the purpose of spinners on propellers?
Spinners are mounted for better aerodynamics, mechanical protection for the hub, and aesthetic reasons.
What materials are spinners typically made from?
They are usually manufactured in one piece from spun aluminium alloy or glass fibre composites.
What should be inspected during spinner installation?
Spinner assemblies should be inspected for warping, cracks, looseness, missing parts, fasteners, improper repairs, or unauthorised modifications.
