Propeller Principles

Question 1

What drag acts 90 degrees to the axis of rotation on a propeller aircraft?

Answer 1

Torque.

Question 2

What is the propeller disc?

Answer 2

The area in which the propeller rotates?

Question 3

Whats the dome of a propeller called?

Answer 3

Spinner

Question 4

Most propellers have approximately blank rpm.

Answer 4

1000

Question 5

What is the component parallel to the rotational axis on a propeller aircraft?

Answer 5

Thrust.

Question 6

• To preserve the same angle of attack along the whole length of the blade, the blade pitch angle must be progressively increased/decreased from root to tip.

Answer 6

Decreased.

Question 7

In a variable pitches propeller, what angle is course?

Answer 7

Large angle.

Question 8

In a variable pitches propeller, what angle is fine?

Answer 8

Small angle,

Question 9

What is variable pitch propeller alpha range?

Answer 9

Flight range.

Question 10

What is variable pitch propeller beta range?

Answer 10

Ground range

Question 11

When would you put a propeller in feathered position?

Answer 11

Engine shut down.

Question 12

When would you use reverse pitch on a variable pitch propeller?

Answer 12

Reverse thrust.

Question 13

What does feathering do to a propeller?

Answer 13

Reduce drag.

Question 14

What can you do to the prop leaver to feather the propeller?

Answer 14

Reduce it

Question 15

When is a propeller on speed?

Answer 15

When propeller torque drag equals engine torque drag.

Question 16

What is a propeller spinner susceptible to?

Answer 16

Icing,

Question 17

What is a propeller driven by?

Answer 17

Engine torque (RPM)

Question 18

What opposes engine torque on a propeller?

Answer 18

Torque drag.

Question 19

The propeller is driven by Engine
Torque (RPM)
• Opposing this is Torque drag which
changes in magnitude with blade angle
• These forces are detected and balanced by the blank?

Answer 19

Constant speed unit.

Question 20

The centrifugal twisting moment in a propeller have a tendency to cause the blade to blank off.

Answer 20

Fine.

Question 21

An aerodynamic twisting moment atempts to blank off the propeller.

Answer 21

Course.

Question 22

When would propeller windmilling occur?

Answer 22

When the engine has failed.

Question 23

What controls the oil in a double Acting Variable Pitch Propeller?

Answer 23

Control speed unit.

Question 24

In a twin engined aircraft, what position does the spring want to move the propeller (Single Acting Variable Pitch Propeller)

Answer 24

Feathering.

Question 25

In a single engined aircraft, what position does the spring want to move the propeller (Single Acting Variable Pitch Propeller)

Answer 25

Fine.

Question 26

The centrifugal latch prevents the blades entering a Blank condition during engine shut down under normal operations on a propeller aircraft.

Answer 26

Feathered.

Question 27

As the csu moves up and the governor weights go out, what happens to the pitch of the propeller fins?

Answer 27

Coarser.

Question 28

CSU on Speed •When propeller torque and engine output are exactly matched the landed valve shuts off the supply of high- pressure blank into the valve chamber • This creates a hydraulic blank which holds the propeller at the selected pitch angle.

Answer 28

Oil - Lock

Question 29

When under speed where do the governor weights move in a csu?

Answer 29

They move in.

Question 30

What is synchro phased condition on a propeller?

Answer 30

Pressure wave taking turns.

Question 31

The "slipstream effect" of a propeller is most prominent at… high/low airspeeds with a high/low power setting

Answer 31

Low speed with high power

Question 32

power lever is moved to the reverse position and the blades move from low pitch ( directly to/via high to )reverse pitch.

Answer 32

Directly to

Question 33

The main advantage of a constant speed propeller compared to a fixed pitch propeller is that a constant speed propeller…maintains its maximum propeller efficiency over a wider range of blanks.

Answer 33

Airspeeds.

Question 34

During cruising flight, when the throttle is pulled back on an aeroplane equipped with a constant speed-propeller, the propeller pitch automatically decreases/increases and the RPM increases/decreases/does nothing.

Answer 34

Decreases and does nothing

Question 35

One of the primary purposes of a propeller reduction gearing system is to…limit the x x x to a value below which efficient operation can be obtained.

Answer 35

Propeller rotation speed.

Question 36

On an aeroplane equipped with a manual feathering system the pilot can feather the propeller by…pulling the propeller control lever forwards/rearwards.

Answer 36

Rearwards

Question 37

In the event of an engine failure during flight in a single-engine aeroplane not fitted with a feathering system, the blades of a constant speed propeller tend to move…towards the smallest/biggest blade angle by blank twisting moment and/or spring force.

Answer 37

Smallest - centrifugal

Question 38

The blade angle of a constant-speed propeller…increases / decreases with true air speed.

Answer 38

Increases

Question 39

An aircraft is performing a go-around having had a critical engine failure. Which of the following combinations gives the BIGGEST stress on the rudder? Forward/aft CG and 1/2slip/no slip

Answer 39

Aft and no slip

Question 40

Assuming the RPM and throttle levers are not altered, when TAS increases the blade angle of a constant speed propeller will… increase/decrease?

Answer 40

Increase

Question 41

A multi-engine piston aircraft both the propellers rotate clockwise as seen from the cockpit. In a go-around, one of the engines fails. Which of the following situations will most probably need the pilot to use full rudder deflection?

Answer 41

Tachometer

Question 42

A multi-engine piston aircraft both the propellers rotate clockwise as seen from the cockpit. In a go-around, one of the engines fails. Which of the following situations will most probably need the pilot to use full rudder deflection? Left/right failure with a left/right crosswind.

Answer 42

Left

Question 43

Consider two twin-engine airplanes: Airplane 1 has clockwise-rotating propellers. Airplane 2 has inward-rotating propellers. If, on both airplanes, the left engine fails, which will give the largest yawing moment, and from which side will it be?

Answer 43

Airplane 1 will have the greatest yaw moment, and it will produce a yaw to the left.

Question 44

For take-off, the correct combination of propeller pitch (high/low), and propeller lever position (forward/aft) for a piston engine at brake release is…

Answer 44

Low / forward

Question 45

After an engine failure on a twin-engined aircraft, which of the following configurations will put the least strain on the rudder? Forward/aft CG and 1/2slip / no slip towards the OPERATIVE ENGINE.

Answer 45

Forward / 0.5 slip

Question 46

What direction do you pull the prop for feathering?

Answer 46

Rearwards

Question 47

One of the primary purposes of a propeller reduction gearing system is to…limit the propeller blank blank to a value below which efficient operation can be obtained.

Answer 47

Rotation speed