Revision Questions Airconditioning

Question 1

The function of the negative pressure relief valve is to -

A. Limit the cabin altitude to a value below or equal to the aircraft altitude
B. Limit the cabin pressure to a value above the outside ambient pressure at all times
C. Limit the maximum positive pressure differential
D. Increase the bleed airflow through the air cycle machine

Answer 1

A. Limit the cabin altitude to a value below or equal to the aircraft altitude

Question 2

The air conditioning system of a large jet aircraft has a water separator designed to -

A. Dry out the moist cool air to prevent respiratory infections
B. Remove water which condensed in the system during the cooling process
C. Increase the humidity of the air flowing to the passenger cabin
D. Prevent ice forming in the ram duct

Answer 2

B. Remove water which condensed in the system during the cooling process

Question 3

If fitted to the air conditioning system of a large jet aircraft, humidifiers are used -

A. Always at high altitude
B. When needed at high altitude
C. Always at low altitude
D. Always at all altitudes

Answer 3

A. Always at high altitude

Question 4

The ram valve in a pressurisation system is used to -

A. Augment conditioned air with ram air supply to the cabin in pressurised flight
B. Provide cooling and ventilation by ram supply into the cabin in unpressurised flight
C. Regulate cabin pressure by controlling ram supply into the cabin
D. Adjust the cabin temperature by blending bleed air and ram air for cabin supply

Answer 4

B. Provide cooling and ventilation by ram supply into the cabin in unpressurised flight

Question 5

In auto mode of a 767 pressurisation system, the required inputs from the crew are -

A. Landing airfield elevation and cabin rate of change
B. Cabin altitude and cruise altitude
C. Required differential pressure
D. Cruise altitude and cabin rate of change

Answer 5

A. Landing airfield elevation and cabin rate of change

Rate of change is in auto position

Question 6

The function of a pneumatic restrictor valve in a large aircraft pneumatic system is to -

A. Vary the direction of the air flow
B. Adjust the speed of the airflow
C. Regulate the pressure of the system
D. Regulate the temperature of the system

Answer 6

B. Adjust the speed of the airflow

Question 7

In the turbine of an air cycle machine, bleed air supplied from engines undergoes -

A. An increase in pressure and decrease in temperature
B. An increase in pressure and an increase in temperature
C. A decrease in pressure and a decrease in temperature
D. A decrease in pressure and an increase in pressure
E. A decrease in pressure and no change in temperature

Answer 7

C. A decrease in pressure and a decrease in temperature