Air Condition Flashcards
With the APU ASGs supplying power to the airplane, how many CACs operate on the ground with an outside air temperature of 70F (21C)
A. All packs
B. 1 per pack
C. 3
B. 1 per pack
What controls the air conditioning pack system components in the pack bay?
A. The pack control unit in the pack bay
B. Software in the common core system (CCS) through remote power distribution units (RPDU) in the pack bay
C. The pack control unit in the opposite pack bay
A. The pack control unit in the pack bay
What is one of the functions of the add heat valve?
A. To increase output flow rate of the CAC
B. To increase output temperature of the CAC
C. To provide primary surge protection of the CAC
B. To increase output temperature of the CAC
During flight, the left air conditioning pack suddenly starts to use more electrical power. What is a possible cause for this?
A. The left lower recirculation fan stopped operation
B. The bearing of the left air cycle machine (ACM) are dry
C. There is a leak in the trim air system downstream of the left trim air pressure
A. The left lower recirculation fan stopped operation
What protects the airplane if a hot duct breaks in the right pack bay?
A. The overheat detection system (ODS) stops operation of the left pack
B. The output temperature of the right pack decreases
C. The overheat detection system (ODS) stops operation of the right pack
C. The overheat detection system (ODS) stops operation of the right pack
What is used to control zone B temperature?
A. Trim air and a zonal duct heater
B. Trim air from the 2 packs
C. Air from the upper recirculation fan
A. Trim air and a zonal duct heater
The flight deck boost fan isolation valve opens to the left boost fan pull conditioned air from the zone A supply duct, what is the purpose of this?
A. To let exhaust air go from the flight deck to the forward cargo compartment
B. To let air go to the flight deck
C. To make sure that air from the alternate ventilation system (AVS) does not go to the flight deck
B. To let air go to the flight deck
The ground call horn is on. A possible cause of this is low air flow in what system?
A. Forward equipment cooling system
B. Lavatory/galley ventilation (LGV) system
C. Miscellaneous equipment cooling system
A. Forward equipment cooling system
On the ground, the aft outflow valve (OFV) ground gate is in the close position. What is a possible cause for this?
A. The forward OFV is in the full open position
B. The aft OFV is in the manual control mode
C. The forward OFV is in the manual control mode
B. The aft OFV is in the manual control mode
After a negative pressure relief condition occurs, what would an inspection on the ground show?
A. No indication that the negative pressure relief valves (NPRV) opened
B. The negative pressure relief valves (NPRV) flapper is in the open position
C. The red band around the edge of the pressure relief valves (NPRV)
A. No indication that the negative pressure relief valves (NPRV) opened
The right power electronics cooling system (PECS) is in operation with a leak detected in the aft part of the system. What does the PECS maintenance page data shows for the right PECS isolation valve?
A. Open to permit PECS flow to the integrated cooling system (ICS) component
B. Closed to stop PECS flow to the high voltage dc components
C. Closes to stop PECS flow to the integrated cooling system (ICS) components
C. Closes to stop PECS flow to the integrated cooling system (ICS) components
The pack control unit sensed a pack overheat and caused a pack trip. This stopped pack operation. How can the flight crew start the pack again?
A. The pack control unit starts the pack again when the overheat condition goes away
B. Cycle the pack switch from OFF to AUTO
C. Momentarily push the AIR COND RESET switch
C. Momentarily push the AIR COND RESET switch
What prevents ice in the air conditioning pack condenser?
A. The low limit valve (LLV)
B. The air cycle machine (ACM) bypass valve (ABV) closes to let more air flow through the condenser
C. The diverter valve of the lower recirculation air heat exchanger opens to increase the temperature of the air that goes to the condenser
A. The low limit valve (LLV)
The cabin crew report shows the temperature selection for the one of the passengers zones is always unusually high, what is a possible cause?
A. Blockage prevents air flow over the related zone temperature sensor
B. The related zone temperature sensor fan does not operate correctly
C. There is a leak in the supply duct to the related trim air pressure regulator valve
A. Blockage prevents air flow over the related zone temperature sensor
How do the lower recirculation air fans help to control the cabin air humidity?
A. The fans move the moist air of the cargo compartments into the air conditioning
B. The fans move dry air from the mix bay area into the air conditioning distribution system
C. The fans move the moist air of the zonal dryers exhaust back into the air conditioning distribution system
C. The fans move the moist air of the zonal dryers exhaust back into the air conditioning distribution system