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1. How many AGUs (Air Generation Units)

2 x ozone converters, 2 x Flow Sensing Venturis (FSV), 2 Flow Control Valves and 1 Full Digital AGU Controllers (FDAC)

2. What are the components involved in flow control and monitoring (Per AGU)

LRU Venturi duct, absolute px sensor, delta px sensor and temperature sensor, FSV is an LRU

3. What does each FSV have

Actual flow calculation, delta P also used for AGU heat exchanger clog detection

4. What are the sensors in FSV used for

Each FDAC compares actual flow to flow demand (from AGS APP) in order to control its FCV torque motor

5. How is this actual flow calculation used

Proximity switch on each FCV will send fully closed/not fully closed posn to the FDAC

6. What is the switch on the FCV for

Two fully redundant digital channels (active and standby), fitted in un px wing root area (AGU bay)

7. How many channels in an FDAC and Where fitted

4 (2x INBD) (2x OUTBD) OUTBD have chk valves

8. How many LP ground connections


9. Which LP connections would you supply first

At rear of FWD cargo hold, lowest selected zone temp

10. Where is the mixer unit installed? What is the temp here

L.H AGU input from FCV 1 + 2, R/H AGU input from FCV 3 + 4 “Each FCV controls half the total flow of 1 AGU”

11. Which FCVs input to which AGUs

Hot air from upstream of the AGU

12. Where is the hot air to the mixer unit supplied from

2 of each

13. How many trim air px reg valves and how many trim air shut off valves

4 HP recirc fans

14. What will supply filtered air to the mixer unit? How many

ERAI (Emergency Ram Air Inlet)

15. What is the guarded P/B ‘RAM AIR’ in the flight deck

Pack 1 CTL (L/H AGU) will reset FDAC 1, and the AGS APP in CPIOM B 1 and 3 Pack 2 CTL (R/H AGU) will reset FDAC 2, and the AGS APP in CPIOM B 2 and 4

16. What will the Pack 1 and 2 CTL reset switch reset

Ventilation and Control Modules, 1 in FWD cargo and 1 in AFT cargo

17. What is the VCM? Where fitted

Fire P/B, Pack P/B and VCM command

18. What can cause FCV to close

VCMs monitors the MORV (Mixer Over Px Relief Valve) on mixer bay and will command closure if mixer over px occurs

19. Why would the VCM command FCV closure

If engines are supplying DSMCU will send door unlocked signal to FDAC which will close FCV to prevent aircraft pressurisation

20. What is the purpose of the DSMCU input to FDAC

Safe mode operation

21. What is the purpose of the flight deck rotary switch ‘AIR FLOW’ MAN selection


22. What APPS are contained in the CPIOM-Bs

Will give purser complete control over individual zone temps via FAP (FLT crew select A/C as 1 zone, single cabin target to TCS)

23. What is the function of the purser select option on the CABIN TEMP select rotary switch

1 ram air inlet, 2 ram air outlets

24. How many ram air inlets/outlets per AGU

1 Per door, 2 x 280VDC brushless 3 phase motors, 28VDC brake which engages on removal of power and an RVDT for feedback (FDAC)

25. Ram air inlet actuator how many per door and Components

1 Per door, 1 x 280VDC brushless 3 phase motor, 28VDC brake which engages on removal of power and an RVDT for feedback (FDAC)

26. Ram air outlet actuator how many per door and Components

2 x Dual heat exchangers per AGU

27. How many heat exchangers per AGU

4 per ACM, 2x turbine, 1x compressor and 1x fan

28. How many wheels (spools) per ACM and What are they

Suck in ram air when on GND

29. What is the purpose of the fan

To prevent build up of frost and snow

30. What is the purpose of the AGU check valve

Control AGU outlet temp in conjunction with ram air modulation, by mixing pri heat ex air with 2nd stage turbine discharge (ACM), 2 per AGU

31. What is the purpose of the TCV (Temperature Control Valve) and How many per AGU

Controls the condensing temperature above freezing point (2.2degrees) to prevent icing in the condenser by bypassing first stage turbines, 2 per AGU (abnormal ops as norm by condenser inlet temp sensor)

32. What is the purpose of the TBV (Turbine Bypass Valve) How many per AGU

Gives increased ventilation flow at altitudes > 29000ft by bypassing 1st stage turbines (1 per AGU)

33. What is the purpose of the altitude valve? How many per AGU

Abnormal ops, commands ACM off if system failure occurs, 1 per AGU

34. What is the purpose of the ACM isolation valve? How many per AGU

ACM discharge temp (AGU outlet)

35. Which temperature is displayed at the top of the ‘BLEED’ page

Primary heat exchanger

36. Where does extracted water go

Emergency Ram Air Inlet, ventilation function in case of loss of both AGUs

37. What is ERAI? Function

2 x scoops under belly, 1 actuator per scoop that will extend to close scoop, conn into LP gnd air, 4 internal limit switches installed in pairs at each end of actuator travel

38. How many ERAI scoops? Actuators? Actuator position to close? Switches

VCM FWD will under VCS APP authority auto opens ERAIs if 2 AGUs off and open signal enabled by CPCS APP (overcome chk valve to enter mixer)

39. Logic and components that will auto open ERAIs

ERAIs commanded to closed position and open signal will be inhibited, highest priority to close scoops

40. What will have to ERAIs if ditching P/B is pushed? Priority

16, 1 flt deck and 15 cabin

41. How many cabin zones

2, L and R

42. How many hot air systems

FCV 2 and 3 norm supply, 1 and 4 can supply in abnormal conditions

43. Which FCVs normally supply hot air system and is there any back up

Trim Air Pressure Regulating Valve (torque motor ctl) x2 installed in AGU bay area, shut off and px regulating functions

44. What is a TAPRV, how many are installed and what are their Main functions

Trim Air Shut Off Valve. X2 installed in mixer unit area, splits air between L/H and R/H systems, normally closed

45. What is a TASOV, how many are there and where installed. What is their Function and Norm position

Trim Air Valve, 1 per zone installed in mixer bay area, has prox switch for fully open

46. What is a TAV, how many, Where, Any switches and why

1 x servicable TAV, 1 x duct temp sensor and 1 x zone temp sensor

47. What components are required for temperature regulation of a zone

Associated TAPRV and TAVs

48. What valves will close if HOT AIR P/B selected off

Quadrant is inbetween TASOV (x2) and TACKV (x4) (Trim air Check Valve)

49. The system has a quadrant architecture, which components define a quadrant

Cabin sensors via CAXS, FLT deck via avionic cooling system, located RHS cabin

50. How are zone temp sensors aspirated? Where located

Trim Air Drive Device installed at rear part of L/H FWD cargo triangle, drives valves based on commands

51. What is TADD, where installed? Basic function

2 x fully redundant channels

52. How many channels in TADD

TCS APP in CPIOM-Bs (>AGS>FDAC>TCV) TADD does not receive

53. What is responsible for lowest selected zone temp

Some to CIDS and some to CPIOM-Bs

54. What systems will receive Zone temp sensor analog signals

TCS 1, TADD channel 1 and TCS APP in CPIOM – B1 and B3 TCS 2, TADD channel 2 and TCS APP in CPIOM – B2 and B4

55. What will the TCS 1 and TSC 2 reset switches reset

ECAM COND page will show lowest and hottest cabin zone temp range (uppr and lwr)

56. What zone temps will be displayed to flight crew and on what page

X 4 SMART fans (S/W loadable) will send air to mixer unit only, installed mixer area

57. HP recirculation system, how many fans and type and were will they send air

Supply a co-annular flow of re-circ air and AGU air to prevent ice build up into mixer

58. What is the purpose of the spiral housings in the HP recirc system

Lower deck area

59. Where is HP re-circ air taken from

Measure average air Px of mixer unit, mixer unit pressure control through HP recirc fan speed command

60. What are the 4 pressure sensors installed in the mixer bay for

Used to re-circ upper deck air into riser ducts for upper and main deck supply

61. What is the purpose of the LP recirc system

X9 fans (1opt), 4 have mufflers fitted (page 70)

62. How many LP recirc fans, how may have mufflers installed

Sidewalls of upper deck

63. Where are the LP Fans and filter assys installed

Between upper deck and main deck, each side of fuse

64. Where is the LP manifold

VCS APPs will control, VCM will monitor

65. What will control LP AND HP fans and fans speed, what will monitor

VCS 1, CH 1 of FWD and AFT VCM, VCS APP in CPIOM – B1 and B2 VCS 2, CH 2 of FWD and AFT VCM, VCS APP in CPIOM – B3 and B4

66. What will VCS 1 and 2 resets breakers reset

Each (4) CPIOM – B VCS APP can control each HP fan L/H LP fans via B1 and B3 R/H LP fans via B2 and B4

67. How is CPIOM application control over LP and HP divided

VCM.s take control, and will operate to a default speed VCM FWD will do all L/H fans VCM AFT will do all R/H fans

68. If fan control via can bus is not possible how is control achieved? By what

At least 1 fan overheat condition

69. What would cause the fault light in the OVHT COND FANS RESET P/B to illuminate

VCS 1 + 2 R/Bs

70. Which R/B would reset all HP and all LP fans

VCS and AGS, to allow control of Px into mixer (fan speed)

71. Concerning HP recirc which APPs would talk

2 x CAX fans, FWD and AFT, lav/galley etc ventilation, active if aircraft power supplied, VCS APP control, VCM monitored, no selections from flight deck (will suck air out of Aft avionics) also SPDBs

72. CAX fans, how many? Function? When active? Who controls and monitors? Flight deck selections

Isol valves open so over board (less than fan extracts to OFV area)

73. Greater than 1 psi diff, where is CAX air going

2 things, if 1 CAX fan failed or SMOKE condition and cabin air extract P/B selected

74. What would cause CAX fans to run in high speed

Over Px Relief Valve Dump, 2 installed rear pressure bulkhead

75. What are ORVDs? How many? Installed

Over pressure relief (max diff protection) mech ops, sprung closed Emergency ventilation, solenoid will open

76. What are the 2 functions of the ORVDs? Ops


77. What controls ORVD’s

X 4 outflow valves, 2 FWD, 2 AFT

78. How many outflow valves fitted

Differential Pressure Sensor Module, back up system, calculates diff px between ext and cabin

79. What is DSPM? Purpose

Negative relief valves, 2 fitted at aft Px bulkhead, open if external px overcomes springs and cab px

80. How many NRVs? Where? Ops

X 4 OC(S)Ms, 2 in FWD cargo, ctl 2 FWD outflow, 2 in AFT ctl 2 AFT outflow

81. How many OC(S)Ms? Where fitted, what outflow valves controlled

OCSM has high precision pressure sensor used for ACP (pax comfort)

82. What is the difference between OCM and OCSM

ACP (Auto Control Partition), SOP (Safety and Overide Partition) and EPP (Emergency Pressurisation Partition)

83. What are the 3 segregated OSCM partitions


84. Which OSCM is linked to FWS applications via arinc 429

CPCS CMD to ACP, ACP passes to SOP which checks and sends to EPP which carries out structural integrity check and will send CMD to motor if happy

85. Outflow valve movement via CPCS

Crew make V/S or ALT selection (ALT has priority), this goes to SOP which passes to EPP for integrity check, CMD sent to motor

86. Outflow valve movement via Flt deck selections

CPCS 1, CPCS APPs in CPIOM – B1 and B3, OSCMs 1 and 3 CPCS 2, CPCS APPs in CPIOM – B2 and B4, OSCMs 2 and 4

87. What will the CPCS 1 and 2 reset breakers reset

Upper and lower FCRC supplied from mixer unit air, two elec heaters, 2 (EHC) elec heater controllers, 2 x mini FAP (own recirc air)

88. What are the main parts of the FCRC ventilation system

Can bus

89. How does the EHC interface with TCS APP

Via the mini FAP in upper and lower

90. How can you check status, control and reset the system

Starts >26000ft/ >23deg, stops 2 hours prior to TOD, potable water (If heater off by FAP humidification off also)

91. When would humidification in FCRC and CCRC start and stop operating? Water supply

No elec heaters, has a TAV, duct temp sensor and compartment temp sensor

92. When do the electric heaters operate for temp control in the LD CRC


93. How are the inlet and extraction isolation valves controlled (LD CRC)

Bulk cargo ventilation duct (extraction sys)

94. Where does the extraction circuit of the LD CRC connect to


95. What APPs will control FWD cargo hold ventilation

Cold air valve (mixer supply to), 3 x supply isolation valves, 2 x TAVs and 1 x extraction isol valve (L/H to R/H side air flow, dumped next to 2 x fwd outflow valve)

96. What valves are concerned with FWD cargo hold ventilation

VCS APP, valve has 3 posns (TCS to VCS from flight deck selection)

97. What controls the cold air valve

Yes 1

98. Does aft cargo ventilation system use TAV

No TAV, has elec duct heater with 2 separate elements

99. How many trim air valves for bulk cargo heating

LP manifold air

100. What is the air supply for the duct heater in bulk cargo

VCM aft and VCS APP

101. How is the bulk cargo system monitored and controlled

None, cannot add cold air

102. How many cold air valves in AFT cargo and Bulk cargo ventilation system

AVS APPs in CPIOM B3 and B4

103. Avionics equipment ventilation system, where are APPs

2 x (SMART) blower fans, 1 x extract fan and 1 x IFE blower fan (run when power on)

104. How many fans in system? What are they

Overboard Fully open, inboard valve closed

105. On the ground with all engines shut down, what is the position of the overboard valve?/inboard valve

1 inboard engine running, overboard valve closed, inboard valve open, to OFV 1 area

106. What would put system into air mode, what would be position of the valves

Select P/B AVNCS EXTRACT to override, inboard valve closes, small door in overboard valve opens to use diff px for extraction

107. What actions would you take if the extract fan failed in flight

L/H and R/H back up valves can supply mixer unit air to failed side/s

108. What can supply air to system if 1 or both blower fans were to fail

Light on LHS NLG and horn sounds, heated sensors that are cooled by AVS air

109. What indications (outside) would you receive if a CED (cooling effect detector) sensed low flow? How sensed

None, would be a PFR pending item though

110. What indications would the flight crew receive of a blower fan or filter failure

Overboard via venturis

111. How are the aircraft batteries ventilated


112. What will AVS 1 and 2 R/Bs reset

Port by OFV 2 FWD used (DIFF)

113. How is extraction achieved for IFEC equip cooling


114. What controls and monitors IFEC ventilation system

Main back ups have priority, if 1 or both mains in use, IFE back up valve cannot be used, crew will select off

115. What has higher priority, IFEC back up valve or main back up valves

Belly fairing and lower wing (AGU bay/CTR wing box/HP gnd conn ducts/X BLD ducts) Rear fuse compartment (APU compt/APU bleed duct)

116. What areas are ventilated in the unpressurised compartment ventilation system

TSV (Turbofan Supply Valve), a turbo fan, 2 check valves and an air inlet

117. What components in 1 of the two identical subsystems

TSV allows air from pneumatic sys to related turbofan

118. How does system operate on ground

15000ft TSV solenoid closes valve

119. At what altitude will the turbofans switch off

If turbo fan does not switch off at 15000ft, an aneroid capsule will switch fan off at 25000ft

120. What is the safety altitude device


121. What carries out control of turbofans

Electric fan, power on at >9degs, off at take off plus 150 secs

122. What type of fan is the THS blower fan?, when off/on

VCM aft and VCS APP

123. What will control and monitor the THS elec fan

4, Generation, Distribution, Consumption and Control

124. What are the SCS (Supplementary Cooling System Subsystems

2 x SCSC (Supplementary Cooling System Controller) in belly area

125. What are the main controllers of the SCS? How many? Where located

Central Refrigeration Unit, Generation, 2 off controlled by SCSC

126. What is a CRU? What subsystem? How many? Who controls

1 x compressor (cooling control) 1 x heat exch (CONDensor and EVAPorator) 1 x EEV (Elec Expansion Valve) Sensors Ram air inlet/outlet

127. What components in each CRU

Quickly decreases Px of liquid refrigerant – flash evaporation

128. What is the primary function of the EEV

2 x fans (Elec) per CRU

129. How is air driven for CRU ops on GND or low speed ops

RACA door

130. More airflow


131. What liquid is in the cooling loops

2 totally independent loops, L/H and R/H

132. How many distribution loops

Each loop will go through both CRUs, to retain some cooling if failure

133. How are the loops/CRUs arranged, why

Dual pump assy, Filter, Accumulator, monitor and prot devices, piping, SOVs and GSP

134. What will each distribution loop contain

Each SCSC supplies elec power to 1 pump in each loop and controls on alternate days with the other SCSC

135. When will the pump swap over take place

Inlet Px at the pump is sufficient

136. Main function of the accumulator

2 in each loop! L/H SOV 1, L/H SOV 2 R/H SOV 1, R/H SOV 2

137. How many SOVs are in each distribution loop

Release coolant to ambient if over Px occurs, 2 of each

138. What is the function of HPRV and LPRV, how many each

They are cooled via a pick up from there related loop

139. How are the SCSCs cooled

Liquid to air heat exch, fan, local ctl unit,CCV, sensors and drain

140. What main components in an ACU


141. How many ACU sizes available

Coolant Control Valve, adjusts coolant flow rate to the heat exch

142. What is CCV and basic function

Fault light in COOLG P/B on vent panel on, can then make off selection at P/B

143. If there was a fault in the SCS when would indication be received

Auto, allows control via FAP

144. What is the other posn of this P/B, what allow


145. Which APP send signal to illuminate Fault light on this P/B

All 4 CPIOM – As contain SCS ops and Bite

146. What CPIOMs have SCS APPs

Shutdown ACUs

147. What would happen if galley and commercial P/Bs off


148. What will provide the SCS APP with the Cabin config

SCS 1, SCSC 1 and SCS in CPIOM A1, A3 SCS 2, SCSC 2 and SCS in CPIOM A2, A4

149. What will the SCS 1 and 2 R/Bs reset