Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

PPL - AGK > Propeller & Variable Pitch Propeller > Flashcards

Propeller & Variable Pitch Propeller Flashcards

(62 cards)

Start Studying
1
Q

Creating forward movement from a propeller is the method of turning ____ motion into ____

A

Method of turning reciprocal motion into thrust

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the 2 types of propeller

A
  1. Fixed pitch
  2. Variable pitch
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

The amount of lift produced by a propeller blade is dependant on what 2 factors

A
  1. Speed
  2. AoA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Why is an propeller designed to have less AoA at the tip than at the hub

A

Tips travel faster
More lift would be produced
More AoA at hub than at tips

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

If a propeller blade had the same AoA across its entire length, which section of the propeller would produce more lift?

A

THE TIP
The tip has greater distance to travel
It travels faster so would produce more lift with the same AoA as the centre of the blade

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

At the hub of a propeller blade, AoA is HIGHER or LOWER than the AoA at the tip

A

Hub = HIGHER
Tip = LOWER

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The AoA of a propeller blade is dependent on which 2 factors

A
  1. Propeller Pitch (Blade angle)
  2. Forward Velocity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

You can determine how far a propeller moves forward in one revolution based on what?

A

GEOMETRIC PITCH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

The efficiency of fixed pitch propeller varies with what

A

AIRSPEED

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Fixed pitched propeller in a climb, assuming power (throttle) constant

Airspeed INCREASES or DECREASES

A

DECREASES

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Fixed pitched propeller in a climb, assuming power (throttle) constant

Relative airflow angle INCREASES or DECREASES

A

INCREASES

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Fixed pitched propeller in a climb, assuming power (throttle) constant

Propeller AoA INCREASES or DECREASES
This has what effect on efficiency

A
  1. AoA INCREASES
  2. Efficiency DECREASES
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Fixed pitched propeller in a climb, assuming power (throttle) constant

Propeller is EASIER or HARDER to push through the air
This has what effect on engine workload

A
  1. HARDER
  2. Workload INCREASES
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Fixed pitched propeller in a climb, assuming power (throttle) constant

Engine RPM INCREASES or DECREASES

A

DECREASES

AoA has increased, prop takes bigger bites of the air
This takes more effort. Engine works harder and turns more slowly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Fixed pitched propeller in a descent, assuming power (throttle) constant

Airspeed INCREASES or DECREASES

A

INCREASES

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Fixed pitched propeller in a descent, assuming power (throttle) constant

Relative airflow angle INCREASES or DECREASES

A

DECREASES

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Fixed pitched propeller in a descent, assuming power (throttle) constant

Propeller AoA INCREASES or DECREASES
This has what effect on efficiency

A
  1. AoA DECREASES
  2. Efficiency INCREASES
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Fixed pitched propeller in a descent, assuming power (throttle) constant

Propeller is HARDER or EASIER to push through the air
This has what effect on engine workload

A
  1. EASIER
  2. Workload DECREASES
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Fixed pitched propeller in a descent, assuming power (throttle) constant

Engine RPM INCREASES or REDUCES

A

INCREASES

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

On an RPM gauge what is meant by the following

  1. Green Arc
  2. Red Line
A
  1. Normal Operating Range
  2. Never Exceed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are 2 examples of propeller aerofoil damage
What effect does this have on efficiency

A
  1. Stone Chips
  2. Tip Damage
  3. Propeller less efficient
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

A propeller under high stress loads could suffer from what

A

STRUCTURAL FATIGUE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

If a small part of a propeller tip were to detach, what could this result in

A

SEVERE VIBRATION

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is a key reasons for an engineering filing out nicks on a propeller blade

A

Prevent fatigue cracks forming and spreading

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
# A variable pitch propeller With a higher AoA; 1. ____ Lift 2. ____ to push through the air
1. GREATER LIFT 2. MORE DIFFICULT
26
# A variable pitch propeller creates With a lower AoA; 1. ____ Lift 2. ____ to push through the air
1. LESS LIFT 2. LESS DIFFICULT
27
# A variable pitch propeller Why do you change the blade angle at different airspeeds
Maintain best AoA
28
# A variable pitch propeller With a low forward speed (start of take off run), what happens to the flyweight, and what pitch angle is selected as a result
1. MOVE IN 2. FINE PITCH | Low blade angle
29
# A variable pitch propeller With a high forward speed (high speed descent), what happens to the flyweight, and what pitch angle is selected as a result
1. MOVE OUT 2. COARSE PITCH | High blade angle
30
# A variable pitch propeller Beyond what 2 limits will a variable pitch propeller become inefficient
1. FINE PITCH STOP 2. COARSE PITCH STOP
31
The mechanism that does automatic blade angle adjustment is known as what
CONSTANT SPEED UNIT (CSU)
32
# Variable pitched propeller in a climb, with power (throttle) constant Propeller adjusts blade angle to INCREASE or REDUCE AoA
REDUCE AoA
33
# Variable pitched propeller in a climb, with power (throttle) constant When the propeller adjusts the blade angle, this makes the propeller EASIER or HARDER to push through the air What effect does this have on engine workload
1. EASIER 2. REDUCED workload
34
# Variable pitched propeller in a climb, with power (throttle) constant If the propeller blade angle is adjusted and engine workload reduces, what effect does this have on RPM
RPM RECOVERS ## Footnote Engine RPM reduces on climb Blade angle reduces the blade AoA Propeller is easier to push through air, reducing engine workload This allows RPM to recover
35
In a CSU unit, what mechanism does oil pressure act against
SPRING
36
#In a CSU Unit 1. What does the spring try to do to the propeller pitch 2. What is the oil pressure doing in response to this
1. Force fully coarse pitch 2. Acts against spring (fine pitch)
37
# Variable pitch propeller If a pilot sets low RPM, what pitch angle is set
LOW RPM = HIGH PITCH | High pitch = Coarse Pitch
38
# Variable pitch propeller If a pilot sets high RPM, what pitch angle is set
HIGH RPM = LOW PITCH | Low pitch = Fine pitch
39
With an increased RPM in a CSU, what will happen to the flyweight
MOVE OUTWARDS
40
# In a CSU, if the flyweight move out, what effect does this have on; 1. Oil pressure 2. Spring position
1. DECREASED PRESSURE 2. COARSE AoA
41
# In a CSU, if the flyweight moves in, what effect does this have on; 1. Oil pressure 2. Spring position
1. INCREASED PRESSURE 2. FINE AoA
42
# Variable pitch propeller An aircraft accelerating (descending) results in MORE or LESS inflow, which INCREASES or DECREASES the effective AoA. The flyweight will move IN or OUT
1. MORE inflow 2. DECREASED AoA 3. OUT
43
# Variable pitch propeller An aircraft decelerating (climbing) results in MORE or LESS inflow, which INCREASES or DECREASES the effective AoA. The flyweight will move IN or OUT
1. LESS inflow 2. INCREASED AoA 3. IN
44
# Variable pitch propeller As AoA decreases, the propeller is doing MORE or LESS work. RPM INCREASES or DECREASES
1. LESS work 2. INCRESED rpm
45
# Variable pitch propeller As AoA increases, the propeller is doing MORE or LESS work. RPM INCREASES or DECREASES
1. MORE work 2. DECREASED rpm
46
# Variable pitch propeller A pilot adjusts RPM control to LOW RPM. What effect does this have on the prop pitch
MORE COARSE
47
# Variable pitch propeller A pilot adjusts RPM control to HIGH RPM. What effect does this have on the prop pitch
MORE FINE
48
What colour is the RPM lever
BLUE
49
What colour is the Throttle lever
BLACK
50
# Constant Speed Unit (CSU) The blue lever controls ____ and instrumentation shows ____ via the ____ gauge
1. RPM 2. RPM 3. RPM gauge
51
# Constant Speed Unit (CSU) The black lever controls ____ and instrumentation shows ____ via the ____ gauge
1. POWER 2. POWER PRODUCED 3. MANIFOLD PRESSURE GAUGE
52
What does a Manifold Pressure (MAP) gauge messure
Pressure in the throat of the carburettor | Mounted after the butterfly valve
53
When the butterfly vavle is shut, the MAP gauge will indicate a HIGH or LOW pressure reading
LOW READING
54
When the butterfly valve is fully open, the MAP gauge will indicate a HIGH or LOW pressure reading
HIGH READING
55
Under what circumstance may a MAP gauge indicate a much higher than atmospheric pressure
Super or Turbo Charged engines
56
What happens to the engine if the wrong order of altering the MAP and RPM is applied?
LABOURED ENGINE
57
# CSU and Engine management What are the 3 steps to INCREASE power
1. Increase **R**EVS 2. Increase **P**RESSURE 3. Check **M**IXTURE ## Footnote **REMEMBER:** Increase R P M, throttle FORWARD RPM --> RPM -->
58
# CSU and Engine management What are the 3 steps to DECREASE power
1. Check **M**IXTURE 2. Reduce **P**RESSURE 3. Reduce **R**EVS ## Footnote **REMEMBER:** Decrease RPM, throttle BACK RPM <-- RPM <--
59
Where can a pilot find the allowable combinations of MAP and RPM for a given flight configuration
PIlot Operating Handbook (POH)
60
# CSU and Engine Management During descent, what will happen to atmospheric pressure What will happen to MAP if unchecked
1. INCREASE 2. INCREASE
61
# CSU and Engine Management During ascent, what will happen to atmospheric pressure What will happen to MAP if unchecked
1. DECREASE 2. DECREASE
62
What are 3 possible failure scenarios of a variable pitch propeller
1. Oil Pressure 2. CSU 3. Pilot Action

PPL - AGK (20 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions