Propellers

Question 1

The propeller control system is divided into two types of control, what are they?

Answer 1

Flight and Ground operations

Question 2

What is the purpose of a propeller?

Answer 2

To create thrust

Question 3

What are two types of propeller configurations?

Answer 3

Tractor and pusher type

Question 4

What type of propeller has the blade angle built into the propeller and cannot be changed?

Answer 4

Fixed pitch

Question 5

What is the purpose of the metal tipping on the leading edge of a wooden propeller?

Answer 5

Protect the propeller from FOD damage

Question 6

What tool is used to determine propeller blade angle?

Answer 6

Universal propeller protractor

Question 7

What are the aerodynamic forces and loads acting on a rotating propeller blade?

Answer 7

Centrifugal force, aerodynamic twisting, centrifugal twisting, torque bending, and thrust bending forces

Question 8

What is the meaning of propeller blade “back” and “face”?

Answer 8

The curved side is called the blade back. The flat side is called the blade face

Question 9

What should be used to clean aluminum and steel propeller blades and hubs?

Answer 9

Suitable cleaning solvent using a brush or cloth

Question 10

What positions are used on a balance stand to check a two bladed propeller for static balance?

Answer 10

First the vertical position, then the horizontal position

Question 11

Can a fixed pitch propeller’s pitch be changed?

Answer 11

No

Question 12

Why do you put the blades of a counterweight propeller into high pitch before stopping the engine?

Answer 12

In this position the piston is protected from dirt and moisture in the air

Question 13

Why are cones installed on splined shafts with a propeller?

Answer 13

The cones center the propeller on the shaft

Question 14

How is feathering accomplished on a constant speed counterweight propeller?

Answer 14

By releasing the governor oil pressure on the counterweights. The feathering spring moves the blades to the feathered position and the oil returns to the engine.

Question 15

What types of systems are used for deicing propellers?

Answer 15

Fluid or electrical deicing systems

Question 16

What is the purpose of a slinger ring on some propeller installations?

Answer 16

Deicing fluid is ejected from a stationary nozzle on the engine into a u-shaped channel, known as the slinger ring, attached to the rear of the propeller assembly

Question 17

What is blade tracking?

Answer 17

Determining the position of the tips of the propeller blades relative to each other

Question 18

Do the counterweights on a constant speed propeller increase or decrease the blade angle?

Answer 18

Increase the pitch of the blades

Question 19

What should you adjust if a pilot requests 50 more RPM on an aircraft equipped with a constant speed propeller?

Answer 19

Governor’s prop-level set screw

Question 20

What adjustments are powerplant mechanics allowed to make to the prop governor?

Answer 20

Maximum RPM stop

Question 21

Why are propellers indexed to the crankshaft for an engine?

Answer 21

Reduce vibrations

Question 22

Can transverse cracks in a propeller be repaired?

Answer 22

No

Question 23

What is the alpha range and beta range of a propeller?

Answer 23

Beta range is the condition of the propeller during ground operations and in the reverse pitch position. Alpha range is propeller position in flight.

Question 24

When changing metal bushings on a wooden propeller assembly, a thorough inspection of the bolt holes should be accomplished. Why?

Answer 24

Check for elongation

Question 25

How are wooden propellers cleaned?

Answer 25

Soap and water

Question 26

What happens to a constant speed feathering propeller when the propeller governor’s oil pressure drops to zero PSI?

Answer 26

Returns to the feathered position

Question 27

What is the purpose of an arbor when balancing a propeller?

Answer 27

Support the propeller on the balance knives

Question 28

What two forces are balanced in a propeller governor in an on-speed condition?

Answer 28

Speeder spring and flyweights

Question 29

How do you determine the repairability of a damaged propeller blade?

Answer 29

Reference the manufacturer’s maintenance manual

Question 30

When engine vibration is reported, what should be checked to determine if it is caused by the engine or the propeller?

Answer 30

Blade tracking and blade angle setting

Question 31

What positions of a two blade propeller are used during a static balance test?

Answer 31

Vertical and horizontal

Question 32

What three things does a typical constant speed propeller governor accomplish when operating?

Answer 32

Boosts engine oil pressure before it enters the propeller hub, controls the amount of oil that flows to the propeller, senses the rotational speed of the engine

Question 33

What pitch will a constant speed propeller move into at constant power when going into a nosedive?

Answer 33

High pitch.

Question 34

What is the device that reduces vibrations in an aircraft with multiple propellers?

Answer 34

Propeller synchronizers.

Question 35

Why is an oil accumulator connected to the prop governor?

Answer 35

To assist with unfeathering the propeller.