Midterm Flashcards
A device for converting engine horsepower into usable thrust
propeller
A propeller used on light aircraft, whose blade angles cannot be changed
fixed pitch propeller
a propeller whose pitch can be changed in flight by the pilot’s control lever or switch
controllable-pitch propeller
the angle between the blade section chord line and the plane of rotation of the propeller
blade angle
a system which uses a governor to adjust the propeller blade angle maintain a selected RPM
constant-speed propeller system
the rotation of the propeller blades to an angle of about 90 degrees which will eliminate the drag of a windmilling propeller
feather
rotating of the propeller blades to a negative angle to produce a braking or reversing thrust
reversing
one arm of a propeller from the hub to the tip
blade
the central portion of a propeller which is fitted to the engine crankshaft and carries the blades
hub
forward edge of the propeller blade
leading edge
the curved side of a propeller airfoil section the can be seen while standing in front of the airplane
back
the plane in which the propeller rotates, 90 degrees to the crankshaft centerline
plane of rotation
the imaginary line which extends from the leading edge to the trailing edge of a blade airfoil section
chord line
a distance from the center of the propeller hub measured in inches
blade station
the same as geometric pitch. Often used interchangeably with blade angle
pitch
the twist in a propeller blade along its length
pitch distribution
a propeller which can be adjusted on the ground to change the blade angles
ground adjustable propeller
the propeller control device in a constant-speed system
governor
What is the smallest division that can be read with a propeller protactor?
tenths of a degree
What should be the condition of the cockpit controls before working near a propeller?
Magneto switch is off and key is removed from the switch. Mixture control is in the idle cutoff position and master switch is in the off position.
Which FAR defines the different classes of maintenance for the propeller systems?
FAR Part 43
What information is required to be on the hub or clade butt of a propeller?
Builder’s name, model designation, serial number, type certificate number, and production certificate number
What is the minimum ground clearance for the propeller on a tricycle-geared aircraft?
7 inches
the angle between the chord line of a propeller blade section and the relative wind
angle of attack
the force which tries to pull the blades of the hub
centrifugal force
force that tends to bend the propeller blades forward at the tips
thrust bending force
force which tends to bend the propeller blade back in the direction opposite to the direction of rotation
torque bending force
force that tends to increase the propeller blade angle
aerodynamic twisting moment
force that tends to decrease blade angle and opposes aerodynamic twisting moment
centrifugal twisting moment
the rpm range at which destructive harmonic vibrations exist
critical range
the theoretical distance that an aircraft will move forward in one revolution of the propeller
geometric pitch
the distance forward that an aircraft actually moves in one revolution of the propeller
effective pitch
the difference between geometric and effective pitch
slip
a crankshaft whose propeller mounting surface forms a flat plate 90 degrees to the shaft centerline, med hp engine
flanged
a cylindrical-shaped crankshaft extension which has splines on its surface to prevent propeller rotation on the shaft, high hp engines
splined
a crankshaft design whose propeller-mounting surface tapers to a smaller diameter and acts like a cone seating surface, low hp engines
tapered
