PPL-AGK

Question 1

What is the crankshaft responsible for?

Answer 1

Turning the linear motion of the piston into rotational motion of the propeller

Question 2

What does the camshaft do?

Answer 2

Provides the timing sequence for the intake and exhaust valves

Question 3

What is the intake manifold

Answer 3

The ‘tube’ that the gas flows through into the cylinder

Question 4

What is the outlet manifold

Answer 4

The ‘tube’ that exhaust gases flow out from the cylinder

Question 5

What are the four stages of the otto cycle?

Answer 5

Induction
Compression
Combustion
Exhaust

Question 6

How many revolutions of the crankshaft are involved in one cycle

Answer 6

2

Question 7

power output depends on what?

Answer 7

The amount of gas induced into the cylinders

The temperature reached during combustion

Question 8

When is engine overspeed most likely to occur given no power changes

Answer 8

descent

Question 9

Complete combustion only occurs at…

Answer 9

The stoichiometric ration (15:1)

Question 10

Air and fuel mixture will burn between

Answer 10

8:1 (rich) and 20:1 (lean)

Question 11

what is the advantage to a richer mixture

Answer 11

Aids in engine cooling (result of excess fuel)

Question 12

What is density affected by

Answer 12

Pressure
Altitude
Temperature

Question 13

When does detonation occur

Answer 13

With spontaneous explosive combustion

Question 14

What are some common causes of detonation

Answer 14

High CHT
bad/wrong fuel
over-leaned mixtures

Question 15

What is an octane rating

Answer 15

resistance to detination

Question 16

What are some symptoms of detonation

Answer 16

high CHT
significant power loss
Engine vibration
pinging sound

Question 17

If detonation is occurring, what actions should be undertaken

Answer 17

reduce power
increase IAS
richen mixture

Question 18

What is pre-ignition

Answer 18

when the mixture ignites before the spark plugs fire

Question 19

What are some causes of pre-ignition

Answer 19

Cylinders too hot
high power with lean mixture
overheated spark plugs

Question 20

What are some symptoms of pre-ignition

Answer 20

rough running
backfire
high CHT

Question 21

What pressure is used for fuel delivery in a carby

Answer 21

low pressure

Question 22

What pressure is used for fuel delivery with a fuel injected system

Answer 22

high pressure

Question 23

avgas 100/130 colour

Answer 23

green

Question 24

avgas 100ll colour

Answer 24

blue

Question 25

avtur colour

Answer 25

yellow

Question 26

mogas colour

Answer 26

red

Question 27

why is the fuel tank vent important

Answer 27

it prevents excessive pressure buildup and thus prevents implosions or tank damage

Question 28

what part of the carby sucks fuel to get mixed with air

Answer 28

the venturi

Question 29

What are the three types of carby icing

Answer 29

``` Impact ice (ice occurs on walls) Evaporation ice (fuel vaporises) Throttle ice (pressure drop results in temperature drop) ```

Question 30

What is a symptom of carby icing

Answer 30

Drop in rpm without movement of the throttle

Question 31

What conditions is carby ice most likely to occur

Answer 31

< 20 degrees C | >80% humidity

Question 32

What does carby heat do

Answer 32

Use heat from the engine rather than the intake

Question 33

Why is carby heat use on the ground undesirable

Answer 33

unfiltered air=bad for the engine

Question 34

Why do we want the carby heat OFF during take-off

Answer 34

warmer air=less dense air=less power output

Question 35

What doe the accelerator pump do?

Answer 35

Adds additional fuel to the air/fuel mixture to compensate for the lag that otherwise would occur (because the air travels faster than the fuel=leaner mixture=less power)

Question 36

What are two core disadvantages to a carby system

Answer 36

Carby icing | Can't be operated inverted

Question 37

Why is the correct amount of fuel sent to the fuel injector nozzle in a fuel injection system?

Answer 37

Because the Fuel Control Unit monitors the position of the throttle and adjusts accordingly

Question 38

What two sources of power are available for a fuel pump

Answer 38

electrical system | Engine

Question 39

In the event of a fuel pump malfunction, what will occur

Answer 39

bypass opens allowing fuel to flow around the pump

Question 40

Is higher or lower temperature fuel more likely to vaporise?

Answer 40

high temperature

Question 41

Vapour locks can occur in what type of fuel system

Answer 41

Fuel injection system

Question 42

What is one way to alleviate a vapour lock

Answer 42

fuel pump/boost pump

Question 43

What is a likely indication of fuel vaporisation/vapour locks

Answer 43

fluctuating fuel pressure gauge

Question 44

define the chordline

Answer 44

straight line joining the leading edge and the trailing edge

Question 45

define the angle of attack

Answer 45

angle between chordline and relative airflow

Question 46

The single force that lift acts through is known as the

Answer 46

centre of pressure

Question 47

When will rpm be constant in terms of torque

Answer 47

Engine torque=Propeller torque

Question 48

If engine torque > propellor torque, what happens to rpm

Answer 48

increase

Question 49

If engine torque < propellor torque, what happens to rpm

Answer 49

decrease

Question 50

Coarse pitch propellors are most suitable for what airspeeds

Answer 50

High

Question 51

Fine pitch propellors are most suitable for what airspeeds

Answer 51

low

Question 52

What does a constant speed unit do?

Answer 52

Varies the pitch of the propellor to maintain an optimum angle of attack

Question 53

What is the aerodynamic twisting moment

Answer 53

A force which attempts to twist the blade towards coarse pitch ( a result of the total reaction force)

Question 54

What is the centrifugal twisting moment

Answer 54

The natural tendency for any rotating body to align itself with the plane of rotation (attempts to achieve fine pitch)

Question 55

Which is stronger, CTM or ATM

Answer 55

CTM

Question 56

Why are propellors twisted

Answer 56

Because if they weren't, the outside travels further (therefore faster), and thus produces more thrust than the inside, resulting in uneven thrust being produced and the propellor bending.

Question 57

What does the term 'feather' refer to when talking about propellors

Answer 57

When the blade chord line is parallel with the aircraft's relative airflow, minimising drag, and stopping the propellor from spinning.

Question 58

When reducing power on aircraft with pitch control, what rule can we follow

Answer 58

power down prop down

Question 59

When increasing power on aircraft with pitch control, what rule can we follow

Answer 59

mix up, prop up, power up

Question 60

CTM moved blades towards what pitch

Answer 60

Fine

Question 61

Hartzell is associated with .... pitch

Answer 61

fine

Question 62

McCauley is associated with .... pitch

Answer 62

coarse

Question 63

When is spark plug fouling most likely to occur

Answer 63

Low power settings when engine isn't warm enough to burn excess oil

Question 64

What is a gyroscope

Answer 64

An object that has mass and is rotating

Question 65

What is rigidity

Answer 65

The tendency for an object to get all of its mass in the same plane of rotation

Question 66

What 3 factors affect rigidity

Answer 66

Mass Radius of mass from the object Angular velocity

Question 67

What is precession

Answer 67

The tendency to resist a force in one spot and displace it by 90 degrees in the direction of motion

Question 68

Why would electric gyros be necessary at high altitudes

Answer 68

Because it is likely that not enough vacuum can be generated

Question 69

What is the advantage of a vacuum driven gyroscope

Answer 69

Independent of electrical system

Question 70

What are the advantages of electrically driven gyroscopes

Answer 70

Operate more efficiently (more predictable)

Question 71

The AH operates off which gyroscopic principle

Answer 71

rigidity

Question 72

The DG operates off which gyroscopic principle

Answer 72

rigidity

Question 73

The turn coordinator operates off which gyroscopic principle

Answer 73

Precession

Question 74

what is PUDSUC (for the ASI)

Answer 74

Pitot blockage under-read descent | Static blockage under-read climb

Question 75

If the static vent becomes blocked, what does the altimeter do

Answer 75

over-reads on descent and under-reads in a climb (remains constant)

Question 76

If the static vent becomes blocked, what does the VSI do

Answer 76

reads zero