Dale Crane Q's

Question 1

Two variables in the angle of attack of a propeller are:

Answer 1

1. engine RPM (rotational speed)
2. Forward velocity (speed of aircraft)

Question 2

The curved surface of a propeller blade is the ______

(back or face)

Answer 2

back

Question 3

The pitch angle and the angle of attack of a propeller blade _______ the same.

(are or are not)

Answer 3

are not

(would only be the same if no forward velocity)

Question 4

Propeller blade stations are measured in inches from the _______ (hub or tip)

Answer 4

hub

Question 5

The actual distance a propeller advances in one revolution in theair is the _________ pitch

(effective or geometric)

Answer 5

effective

Question 6

The difference between the geometric and effective pitch of a propeller is called _____

Answer 6

slip

Question 7

Five factors that affect the amount of thrust produced by a propeller blade are:

Answer 7

1. Airfoil shape
2. Air density
3. Angle of Attack
4. Velocity of airflow
5. Area of airfoil

Question 8

Two things that change on a propeller blade from the root to the tip are:

Answer 8

1. Blade pitch angle
2. Cross section of the blade

Question 9

Increasing the engine RPM with the forward speed remaining constant _________ the angle of attack

(increases or decreases)

Answer 9

increases

Question 10

Five forces acting on a propeller turning at a high speed are:

Answer 10

1. Centrifugal force
2. Thrust bending force
3. Torque bending force
4. Aerodynamic twisting force
5. Centrifugal twisting force

Question 11

The greatest force acting on a propeller is _______ force

Answer 11

centrifugal

Question 12

The force that tries to bend a propeller blade forward is the _____ bending force

Answer 12

thrust

Question 13

The force that tries to bend a propeller blade in its plane of rotation is the ___________ force

Answer 13

Torque bending force

Question 14

Aerodynamic twisting force (ATF) tries to _______ the blade angle

(increase or decrease)

Answer 14

increase

Question 15

Centrifugal twisting force (CTF) tries to ______ the blade angle

(increase or decrease)

Answer 15

decrease

Question 16

The twisting force that has the greater effect on propeller operation is _______ (ATF or CTF)

Answer 16

CTF

Question 17

A fixed-pitch climb propeller has a ______ pitch angle than a cruise propeller

(higher or lower)

Answer 17

lower

Question 18

Centrifugal force acting on the counterweights on a two-position-pitch propeller rotate the blades toward _______ pitch

(high or low)

Answer 18

high

Question 19

The basic difference between a two-position controllable-pitch propeller and a constant-speed propeller is in the control.

In a constant-speed propeller, a ______ replaces the two position valve

Answer 19

governor

Question 20

Multiengine airplanes were made appreciably safer than their single-engine counterpart by the development of the ______ propeller

Answer 20

feathering

Question 21

The blade pitch angle when a propeller is feathered is near _______ degrees

Answer 21

90

(88 degrees)

Question 22

A reversible propeller is a constant-speed propeller whose ______ (low or high) pitch stops can be released so the blades can be moved to an angle that produces thrust in the reverse direction

Answer 22

low

Question 23

The wood used for most commercially made wood propellers is ______

Answer 23

Birch

Question 24

Modern metal propellers are forged from high-strength ________ alloy, and after being ground to their finished dimensions and pitch, they are ______ to protect them from corrosion

Answer 24

aluminium

anodized

Question 25

The two types of propellers that are found on almost all modern airplanes are:

1. ________
2. ________

Answer 25

1. Fixed pitch
2. Constant speed

Question 26

The pitch on all modern constant-speed propellers is changed ________ (electrically or hydraulically)

Answer 26

hydraulically

(oil)