Propellers

Question 1

What is the function of a propeller?

Answer 1

To create thrust to pull or push an airplane through the air

Question 2

How are some wooden propeller blades protected from wear and damage?

Answer 2

By metal tipping fastened to the leading edge and tip

Question 3

What is the difference between a fixed pitch propeller and a controllable pitch propeller?

Answer 3

Fixed pitch – they cannot be changed by the pilot
controllable pitch propeller – it can be changed by the pilot, the blade angles change by the governor and summer even provide her with reverse pitch and feathering

Question 4

What happens to the blade angle of a constant speed propeller during constant power dive?

Answer 4

The blade angle increases to prevent an over speed

Question 5

What are the functions of a constant speed propeller governor?

Answer 5

Boosts engine oil pressure before it enters a propeller hub.
It senses, rotational speed of the propeller
And adjusts the oil flow to the propeller hub the change pitch and therefore speed of the propeller.

Question 6

What is an unfeathering accumulator?

Answer 6

It is an oil accumulator, usually provide oil pressure to unfeather a propeller

Question 7

What is meant when a propeller governor is “on speed” condition?

Answer 7

Is not accelerating or decelerating and the speeder spring and flyweight forces are in balance.

Question 8

How is a constant speed feathering propeller feathered?

Answer 8

By releasing oil pressure in the governor. The counter weights and feathering spring move the propeller into feather or can be moved by the pilot, moving the propeller control into the feathering detent.

Question 9

What is the purpose of propeller blade counterweights?

Answer 9

Forces the blade to a high pitch angle

Question 10

To what do the terms alpha range in beta range pertain?

Answer 10

Those pertain to the operating modes of turbo prop reversible pitch propellers

Question 11

What is the alpha range of a turbo prop?

Answer 11

Alpha – operates in the standard constant speed mode, which is usually in flight

Question 12

What is the beta range of a turbo prop?

Answer 12

Beta – operates in a minimum thrust range and negative thrust or reverse thrust, made, which is usually on the ground

Question 13

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

Answer 13

Speeder ring and fly weight

Question 14

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

Answer 14

The propeller will feather

Question 15

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

Answer 15

By reference to the manufacturers maintenance manual

Question 16

What systems are commonly used for propeller ice control?

Answer 16

Alcohol and electrical heat applied to the propeller blade root

Question 17

What propeller repairs can be performed by a certified mechanic with a power plant rating?

Answer 17

minor repairs and minor alterations

Question 18

How are wooden propellers generally cleaned?

Answer 18

With a brush or cloth in warm water with mild soap

Question 19

Where would you find the correct method and technique for cleaning on aluminum propeller and hub?

Answer 19

The propeller manufacturers manual

Question 20

What type of nondestructive testing should be accomplished to a propeller after bending?

Answer 20

The procedures recommended by the manufacturer

Question 21

What are two criteria used by many manufacturers to determine the amount of blade damage that can’t be repaired by cold bending of aluminum propellers?

Answer 21

The extent of the bend and its blade station location

Question 22

How can repair file marks be removed from an aluminum propeller?

Answer 22

With a very fine sandpaper

Question 23

When performing a static balance on a two bladed propeller, what positions must the propeller be placed with measurements are taken?

Answer 23

Vertical and horizontal positions

Question 24

What is a propeller protractor used for?

Answer 24

It is used to measure the propeller blade angle

Question 25

What blade conditions can cause engine vibration?

Answer 25

Propeller out of track or balance as well as incorrect blade angle settings

Question 26

What is blade tracking?

Answer 26

It is the position of the propeller blade tips relative to each other

Question 27

What controls engine manifold pressure and rpm on an engine equipped with a fix pitch propeller?

Answer 27

The throttle

Question 28

Other than maintaining a constant speed, what are two actions of some controllable propellers

Answer 28

Reverse pitch and feathering