Air Con 13.11.2 Q’s

Question 1

HEPA filters are used in

Answer 1

A cabin air recirculating system

Question 2

If pressurisation air supplies come from an engine compressor an internal oil leak will

Answer 2

Contaminate the air and be hazardous to the passengers and crew

Question 3

International markings for air conditioning pipelines are

Answer 3

Dots

Question 4

Ozone is removed from cabin charge air

Answer 4

At the inlet to the air conditioning system

Question 5

When carrying out a ground pressure run you should use

Answer 5

The aircraft engines because you can test the whole system

Question 6

HEPA stands for

Answer 6

High efficiency particulate arrestor

Question 7

A cabin humidifier is operated at

Answer 7

High altitudes

Question 8

A combustion heater overheats during flight

Answer 8

It will automatically reset but the pilot needs to relight

Question 9

A high pressure water separator in a ACM consists of what heat exchangers

Answer 9

Reheater
Condensor

Question 10

A skin heat exchanger may be used to cool

Answer 10

Electronic equipment

Question 11

Air conditioning systems

Answer 11

Decrease the temperature of the air

Question 12

An air to air heat exchanger in an air conditioning system is provided to

Answer 12

Reduce the air supply temp

Question 13

An aircraft can is air conditioned and pressurised in order to

Answer 13

Maintain human performance and comfort during flights at high altitudes

Question 14

Where is a low pressure water separator located in a ACM

Answer 14

After the turbine

Question 15

How does a combustion heater vary its temp

Answer 15

Switches fuel and ignition on and off as required

Question 16

In air conditioning system distribution the preferred dictons section for wase of manufacturing and fitting and for strength is

Answer 16

Circular

Question 17

Maintenance tasks to be carried out on the air conditioning can be found in

Answer 17

AMM chapter 21

Question 18

On a combustion heater fitted to a rotorcraft where the heat exchanger or the ventilation air temp exceed safe limits

Answer 18

There must be a automatic cut off for ignition and fuel supply at a point remote from the heater

Question 19

Which of the following sometimes inhibits an air conditioning pack

Answer 19

Throttle switches

Question 20

A variable expansion valve in a vapour cycle cooling system is responsive to

Answer 20

The temperature at the evaporator

Question 21

After passing through the primary heat exchangers the supply air in an air cycle system flows to the

Answer 21

Fan

Question 22

What unit in a vapour cycle cooling system serve as a reservoir for the refrigerant

Answer 22

Receiver dryer

Question 23

Air exiting the turbine of an air cycle machine

Answer 23

Will have decreased pressure and temp

Question 24

An advantage of using an air cycle system over the vapour cycle system in large aircraft is

Answer 24

Both air con and pressurisation are obtained

Question 25

What is the condition of refrigerant when it enters the condenser of vapour cycle cooling

Answer 25

High pressure vapour

Question 26

An air cycle machines turbine

Answer 26

Drives a compressor where the temp increases

Question 27

Frost or ice build up on a vapour cycle cooling system evaporator would most likely be caused by

Answer 27

Inadequate airflow through the evaporator

Question 28

An air cycle pack usually has protection temp sensors

Answer 28

At pack out let at the compressor outlet and at the turbine inlet

Question 29

An air cycle system used for air cycle cooling will

Answer 29

Decrease pressure and temp of the charge air

Question 30

Before filling a vapour cycle cooling system

Answer 30

Apply suction to remove air and moisture

Question 31

Humidifiers are operated at

Answer 31

High altitude

Question 32

In a three wheel air cycle machine air circulated from the cabin is directed to the

Answer 32

Efflux turbine / mixer unit

Question 33

In a boot strap air conditioning system a low pressure water separator is located

Answer 33

Down stream of the turbine

Question 34

In a vapour cycle cooling system water will condense from the air at the

Answer 34

Evaporator

Question 35

In pressurised aircraft temperature conditioning is mainly achieved by

Answer 35

Extracting heat from the pressurised air

Question 36

In the case of a vapour cycle cooling system heat is removed from the charge air by

Answer 36

Changing a liquid into a vapour

Question 37

Name the components of a vapour cycle system in order

Answer 37

Compressor condenser expansion valve evaporator

Question 38

One of the principles of cooling employed in an air cycle system is

Answer 38

Conversion of heat energy to mechanical energy in the air cycle machine

Question 39

R134a is used in

Answer 39

A vapour cycle cooling system

Question 40

Temperature control of cabin air is achieved by

Answer 40

Regulating the amount of air bypassing the cooling system

Question 41

The compressor of a vapour cycle cooling system is found to be operating intermittently

Answer 41

This is normal

Question 42

The effective temperature of a cabin is given by

Answer 42

Temperature and humidity

Question 43

The expansion valve in a vapour cooling system is located

Answer 43

Before the evaporator

Question 44

The heat exchanger in a air cycle system is cooled by

Answer 44

Ambient ram air

Question 45

The humidity within a passenger cabin should be

Answer 45

Be between 30% & 70%

Question 46

The purpose of the expansion valve in a vapour cycle cooling system is to

Answer 46

Reduce the pressure of the refrigerant

Question 47

The receiver/dryer in a vapour cycle air cooling system

Answer 47

Removed moisture from the refrigerant fluid

Question 48

The temperature at which an air cycle system outputs conditioned air is determined by

Answer 48

The selected temperature of the coldest cabin

Question 49

The temperature within the cabin of the aircraft is normally selectable between

Answer 49

18-30 degrees centigrade

Question 50

The thermostatic valve sensing bulb is located just before

Answer 50

The evaporator

Question 51

When a new cabin temperature is selected temperature overshoot and hunting is protected by

Answer 51

An anticipator circuit and damping bridge circuit

Question 52

When a vapour cycle cooling system is topped up with refrigerant the new refrigerant is put into the

Answer 52

Low pressure side only

Question 53

When the refrigerant dissipates heat in a vapour cycle system

Answer 53

The vapour converts to a liquid

Question 54

Where is the last stage of cooling in an air cycle system

Answer 54

Expansion tube or space

Question 55

Which of the following can be used on the ground

Answer 55

Turbofan

Question 56

Which refrigerant type is no longer allowed to be use

Answer 56

R12

Question 57

Which vapour cycle air conditioning system component must have protection form ice formation

Answer 57

The evaporator

Question 58

Which vapour cycle system component is located on the aircraft cabin

Answer 58

Evaporator

Question 59

Which vapour cycle system component is required to be most strongly constructed

Answer 59

Condenser

Question 60

Which zone normally has the greatest cooling demand

Answer 60

The flight deck