Propellers

Question 1

With increasing TAS, the angle of attack of the propeller will ___

Answer 1

reduce

Question 2

The propeller pitch angle is the angle between ___ and ___

Answer 2

The plane of rotation and the blade cord line

Question 3

At 0 TAS, the propeller angle of attack is the angle between the ___ ___ and the ___ __ ___

Answer 3

chord line, plane of rotation

Question 4

With a TAS >1, the angle between the resultant airflow and the plane of rotation is called the ___ ___

Answer 4

helical path, or the angle of advance

Question 5

The thrust bending force tries to ___ the blades ___

Answer 5

bend, forward

Question 6

Torque bending force tires to bend the blade in the ___ direction to/as its rotation

Answer 6

opposite

Question 7

Increasing the blade camber will ___ the power absorption capability

Answer 7

improve

Question 8

Geometric pitch is ___

Answer 8

how far the propeller should move forward in one rotation when the helix angle is equal to the blade angle

Question 9

The helix angle will be equal to the blade angle when the angle of attack is ___

Answer 9

zero

Question 10

The effective pitch is ___

Answer 10

how far the propeller actually moves in one revolution

Question 11

The difference between the effective pitch and the geometric pitch is called the ___

Answer 11

propeller slip

Question 12

The blade angle of attack, when the TAS is greater than 0, is the angle between the ___ and the ___

Answer 12

section chordline and relative airflow

Question 13

The advance ratio is ___

Answer 13

A non-dimensional measure of the forward speed in relation to the speed of the tip of the propeller blade

Question 14

The advance ratio formula is ___

Answer 14

Forward Speed / ( Propeller rotational speed x Diameter )

Question 15

Propeller resisting force is the same as ___ force on a conventional airfoil

Answer 15

Drag

Question 16

The aerodynamic turning moment will try to twist the blades to a ___ pitch

Answer 16

coarse

Question 17

Centrifugal turning moment will try to twist the blades to a ___ pitch

Answer 17

fine

Question 18

What is meant by “absorbing power”?

Answer 18

The resisting force must be able to balance engine torque to ensure RPM isn’t too high

Question 19

Increasing chord ___ CTM

Answer 19

increases

Question 20

Torque produces ___, whilst slipstream produces ___

Answer 20

roll, yaw

Question 21

When the RPM lever is moved backwards, the blade pitch becomes more ___ and the rate of descent will ___

Answer 21

coarse, decrease

Question 22

Blade angle of attack is determined by the added vectors of ___ and ___

Answer 22

propeller RPM and TAS

Question 23

Increasing speed at constant RPM will ___ the blade angle of attack

Answer 23

decrease

Question 24

Increasing RPM at constant TAS will ___ the blade angle of attack

Answer 24

increase

Question 25

At constant Mach, the thrust and fuel flow decrease with ___ pressure at constant temperature

Answer 25

decreasing