17.2.3 Blade Nomenclature Flashcards
What changes along the length of a propeller blade?
The aerodynamic cross section and angles of the propeller blade change along its length.
How are measurements identified along the propeller blade?
Measurements are identified by dividing the blade into ‘stations’, which are divisions taken from the center of the hub to the blade tip.
How are the stations on a propeller blade numbered?
Stations are normally numbered from 1 onward in six-inch increments (15 cm) or by the number of inches from the root of the blade toward its tip.
What is the purpose of the master station on a propeller blade?
The master station is where the blade angle is measured, and if correct, indicates that all other blade angles are also correct.
Where is the master station typically located on a fixed pitch propeller?
The master station is normally 75% from the center of rotation on a fixed pitch propeller.
What is the propeller blade angle?
The angle between the blade chord line and the plane of rotation.
What is the propeller face?
The flat thrust producing side of a propeller blade that strikes the air as the propeller rotates.
What is the propeller blade root/shank?
The thickened portion of the blade nearest to the hub that connects the blade root to the aerofoil section.
What is the function of the propeller back?
The back is the curved side of the propeller blade that generates lower pneumatic pressure as the blade rotates.
What is the propeller hub?
The center portion of a propeller to which the blades are attached and connects the propeller to the engine.
What forces must the propeller hub withstand?
The hub must withstand all forces experienced by the propeller during operation.
