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Above 10,000ft

1. When is Oxygen required


2. What is the normal A380 cabin height

Forward RHS cargo bay

3. Where are the oxygen bottles located and how many

Upper avionics compartment (upper emergency electronic bay). 1-4 bottles

4. Where is crew oxygen bottles and how many


5. What pressure are the bottles

Bottles (1850psi), Pressure Reducer/Transmitter(psi), distribution manifold(64-80psi), mask stowage boxes(psi) and the OSCU

6. What are the components of the crew oxygen system and psi in each

OSCU and LP supply Vlv is DC ESS

7. What is the power supply to the system and which bits

A pressures switch operated by the oxygen in the distribution valve of the box

8. What triggers the mask mic to work

N gives altitude variable oxygen/air up to cabin alt of 35000ft where is 100%. 100% gives 99.9999999999% at all altitudes

9. How does N/100% work

Above 30000ft cab alt it can overpressure to force air in lungs

10. What else can the mask do

Forces Oxygen in times of Smoke or Fumes (uses over pressure vlv)

11. What is emergency for

A small vent into mask to keep smoke and fumes out

12. What else does over pressure vlv cause

Press the 100% and make sure no flow. Do the IN SITU TEST

13. What are the last 2 steps of restowing the mask

Above 24% oxygen

14. What defines oxygen rich atmosphere

Naturally ventilated using air flow from DADO panel to outflow valve

15. How is Oxygen Rich Atmosphere avoided

DOOR/OXYGEN page of the ECAM

16. Where do you read the oxygen levels

B for CPCS, C for FWS (flight phase and warnings), G for LGERS

17. Which CPIOMs

3 and 4. (Used as backup)

18. Which IOMs

On valve. Senses fully open/not fully open to OSCU

19. What are the bottle switch location and action

It’s bottle pressure is not taken into consideration

20. What is a consequence of not fully opening the valve

2560 to 3085psi

21. What pressure will the frangible disc rupture

50.5psi for crew (from either LP side or HP side or pressure reducing valve)

22. What pressure blows out the green disc

It’s on the bottle. Reduces px to distribution on LP side (64-80psi), sends px signal from HP side to OSCU, allows replenishment via a non-return valve on HP side, relief vlv on LP @125psi

23. What are the functions of the Reducer/Transmitter and where is it

A tube with a large surface area to dissipate heat during filling

24. What is the thermal compensator

Crew = fwd of fwd cargo door, Passenger = aft of fwd cargo door

25. Location of blow out indicators

ECAM is temperature compensated by a temperature transducer near the cylinders

26. One difference between ECAM and gauge on refill panel

Distribution manifold with test port, LP solenoid vlv with pos switch, s/s pipes and flex hoses, mask boxes

27. What is in the Crew LP supply distribution

O/Head crew oxygen button on ICP 12211VM which elec signal to LP supply vlv using DC ESS

28. What are the electrical signals

AMU to control mask mic ops

29. Where does the mask Door Open signal go

P1 is Dispatch px (all 4/5 members PIN programming knows how many and how many bottles etc), P2 is minimum px (2 occupants 15mins supply)

30. What are the 2 threshold for cockpit HP indication

If PX is between P1 and P2 then amber half box with green digits(on GND no engines only). If PX is lower than P2 then digits and words in Amber and caution OXY CKPT BOTTLE PRESS LO on ECAM EWD

31. Describe the pressure display on ECAM

LP switch detects < 47psi or LP supply solenoid valve closed. Also REGUL PR LO on ECAM SD. On GND only. Signal via OSCU and IOM

32. When is the CKPT Legend shown amber

Above 14000ft cab alt or manually from flight deck

33. When is pax oxygen deployed

131PSI. Over pressure is 170PSI

34. What is the pax oxygen reduced to and what is it’s over pressure relief

-15degs to 70degsC

35. What is the temp range of the temperature transducer


36. What is the max rate of oxygen px increase whilst servicing

2 oxygen regulators, Lo px switch, 2 test ports, 2 main distribution line, a bleed/vent vlv

37. Describe the components of Pax oxygen system

They electrically regulate the pressure to 5psi @ 10,000 to 65psi @40,000ft

38. What do the Oxygen regulators do

1 to open and 1 to close as I/P. Vlv fully open, Valve fully not open or valve fully closed O/P from 2 internal switches

39. What are it inputs and outputs

Intermediate line between reducer/transmitter and regulators. Sends to OSCU and IOMs if below 98psi

40. Where is the low pressure switch and where does it send data to and at what Px

1 in intermediate line and 1 in distribution line

41. Where are the 2 test ports

1 Main Distribution Line on each deck connected fore and aft by Interconnection Lines. Regulators supply the fwd Interconnection Line

42. Describe the distribution system

2 bleed vent valves. Prevents the oxygen doors opening if there is a leak in the regulator shut off valves and allows purging and lets seal on oxygen sys activation so that the doors will release

43. What is installed at the end of the Main Distribution Lines and why

Manual, from CPCS or the altitude switch (in the Main Avionics Bay)

44. How many ways to activate the system and what are they

From the OXYGEN RESET switch if cab alt < 10,000ft.

45. How do you reset the pax oxygen sys

Light stays ON until operation complete (4s)if all relay and all valves correct. If not correct ON remains and also FAULT lt

46. How does the reset work

Uses AFDX to FWS(flight phase), FWS(warnings), CPCS(pressure signals), FMC(Passenger numbers), LGERS(GND/FLIGHT), CIDS(Pre-recorded announcements), IOMs for back-up

47. What systems connect to the OSCU and via what

2 check Vlv’s, 2 shutoff valves, Riser line shutoff check valves, differential px switch.

48. Describe the distribution in the Engine Burst Area

Open for oxy fore to aft, close if aft to fore

49. How do the Check valves operate

If a rupture happens downstream it will close. Only opens with ground ambient conditions

50. When do the riser shutoff/check valves close and open

Senses a difference between each MDL

51. What does the differential pressure switch do

The OSCU (by continuous BITE) has detected an Engine Burst Shut Off valve not Fully Open


10 mins

53. During OXY testing how long must the manual release tool be held in the test port to bleed it



1. What are the controlling bodies and regs for fuel safety

Fuel Airworthiness Limitations and it is added to the Airworthiness Limitation Section part 5

2. What is the doc for Airbus called


3. Another name for vacant tank space

Flash point (lowest temp but needs a thermal source or reach ignition point to continue), ignition point (can continue burning by itself) and Auto ignition (no ignition source needed)

4. What are the key points around which ignition/explosion may occur

Metallic strips attached to non metallic

5. How are the composite rib bonded

Low power supply, connections via terminal block, gap to structure maintained, electrically isolated from structure.

6. How is electrical protection performed

Only essential and limited to sensing and monitoring with very low energy req. In-tank wiring and fuel calculators is separated from other a/c system.

7. What is the wiring in the tanks

Externally actuated dual bonded

8. How are valves made safe

If mounted on a tank boundary they are separated from the fuel by a diaphragm. Electrics are fully sealed and explosion proof

9. How are Switches made safe

Vent with min 1 inlet and 1 outlet. Check with combustible gas indicator after 6 hours venting. Must be < 10% Lower Explosive Limit (LEL). Respirator req if > 5%. And pre tank entry check list completed

10. Tank vent considerations before entry

Overpressure protector has a white Cross outboard of NACA duct. between Ribs 47 and 48

11. What is an alternate way to tell if vent tank has over-pressurised

< 10% fuel qty

12. When should you use the suction fuel water drain method

Using manually operated leak monitor (x3) and the drain mast

13. How are leaks in Trim pipe, APU feed pipe and centre wing tank detected

2 primary upturned outlets and 2 secondary with float valves. A weir duct is installed between ribs 7 and 8 and a float valve inboard of rib 8

14. How are feed tanks 2(3) vented and prevented from siphoning

Back to feed tanks of 1 and 4 via jet pump. ( or over board via vent tank!!)

15. Where does surge tank fuel go

1000 litres. > causes refuelling to stop. WING OVERFLOW msg until level is < 800

16. Max fuel in surge tank

2 FQDC, probes and sensors, IRP, 4 CPIOM-F with APPs

17. What is in the fuel management system

Mostly in CPOIM but also in FQDC

18. Where is the FQMS software hosted

F1 and 3 are side 1 with FQDC 1, F2 and 4 are side 2 with FQDC 2 (odd and even). 1 and 2 are COM. 3 and 4 are MON

19. How are the CPIOMs and FQDC arranged

Measurement, Management, and CG measurement

20. What does COM have

Integrity, Monitor, BITE, CG measurement

21. What does MON have

Receive data from probes an sensors as well as feedback and IRP and sends to CPIOMs via ARINC 429

22. What do the FQDC do

AGP x1 TSP A and B. There are 2

23. How are the apps in FQDC arranged and how many FQDCs are there

Monitor broken APU feed pipe

24. What else do the TSPs do

Primary (software in CPIOMs, Tank Signal Processors in FQDC) and Secondary (Alternate Gauging Processors and independent software and TSP in FQDC)

25. What are the fuel measurement systems and describe them

Group A and Group B. A are done TSP1A + 1B. B are done by TSP2A + 2B. Then data is sent to AGPs and CPIOMs

26. How are the tank components divided

Comparing measured values with threshold values

27. How are flags triggered

CPIOM-F 1 and 2 broadcast via ARINC 429

28. What if the ADCN is lost

Capacitance data from Probes (measure fuel height) , from PROBE Compensator Temp Units (PCTU) (measure fuel permittivity (or dielectric) and Temp) and Fuel Properties Measurements Units(FPMU) and temp sensors.

29. How does the FQMS measure fuel

172 probes and 12 PCTUs

30. How many probes are there

Probe is 2 metallic tubes with a gap, PCTU ha 3 metallic tubes and a temp sensor. If fully immersed it is a compensator.

31. PTCU and Probe differences

Measure permittivity, density and temp of a fuel sample during refuelling only. They are in feed tanks 1, 2, 3. Each has a compensator, a densitometer, 2 temp sensors

32. Describe the FMPU

Dual Temp Sensors (segregated from each other) in L and R outer tank, collector cells and trim tank

33. How is fuel temp measured

Main runs, and stay only if main low px or off. If both pressed in together then Main runs and after 3s stby runs for3s

34. What is normal pump configuration


35. What config are the crossbreeds valves normally

Besides Eng 4 on ECAM fuel page. APU in white line in green means it is being fed (both APU isolation and APU LP valves open)

36. Where can APU fuel indications be seen and what does it display

Fuel is being fed abnormally. (APU in AMBER alone means APU not being fed)

37. What if the APU and line are AMBER

Push and hold the fuel-vent P/B sw. (Valves open APU pump starts if px low at APU inlet)

38. How do you bleed the APU fuel line

The FMS NOT the Active/fuel&load page

39. Where do you get ZFW, ZFWCG and BLOCK from for fuelling from OMT

Fwd gallery for wing to wing, aft gallery for trim tank

40. Which galleries are used for in flight transfers

On ground when primary accuracy 1 to 2 % of tank capacity. In air 2% to 4%

41. When does “GAUGING LO DEGRADATION” appear

Fuel tank digits in green except last 2 are amber with a dashes, FOB and GW last 3 amber dashes, GWCG last digit amber dashes. Also on IRP (obvs all green) dashes on last 2 tank and FOB last 3

42. What else happens with “GAUGING LO DEGRADATION”

On ground when primary accuracy 2 to 10 % of feed tank 1. In air 4% to 10%


Fuel tank digits in green except last 2 are amber with a dashes, FOB and GW last 3 amber dashes, GWCG last digit amber dashes. Also on IRP (obvs all green) dashes on last 2 tank and FOB last 3

44. What else happens with “GAUGING MEDIUM DEGRADATION”

Yes… “FUEL FQI FAULT” if feed tank 1 inaccuracy > 10%. Everything becomes XXXX

45. Does it get worse

Fuel in at least one tank is unusable

46. What does a half amber box mean

Fuel pumps (main and stby in collector cell) collect fuel from collector cells and jet pumps(2 also in each collector cell— 1 for fuel supply the other (smaller) for water scavenge ) to fill the collector cells

47. Briefly describe the fuel feed system

Bottom skin of wing

48. Where are the fuel pump canisters

Front or rear spars. 1 for each pump High or low signal

49. Where are the px switches and what is the signal

115v freq wild converted to DC by and regulated by an electronic controller

50. What is the power used

115VAC SEPDC or relays Main 2 and STBY 3 pumps. The relays receive the px signal so know when to activate stby

51. Where does the supply come from

Only the Main 2 and stby 3 pumps are supplied and controlled by aircraft wiring

52. What happens in emergency

GFI between the busbars (other pumps Gfi function is from SEPDC)

53. How are Main 2 and STBY 3 pumps protected

Brushless DC

54. What type of motor is it

A check valve in each canister

55. How is reverse flow prevented if pumps off

Bleeds off air and prevents over pressure of fuel between closed valves also

56. What is the air release valve

Front spar in respective fuel feed pipes in the fuel tank adjacent the engine pylon. They are a ball type valve driven by Twin Motor Actuators (TMA). They send a feedback signal. They live in a fireproof box

57. Where are the LP valves and what type are they?

A clear window on the cover lets you see the driveshaft. White slot aligns with O or C

58. How can you visibly see the LP valve position

DC ESS motor 1 and DC2 for motor 2

59. What are the power supplies for the LP Valves

By FQMS after last engine shutdown. Each motor full open close separately. Also crossfeed valves tested too

60. When are the LP valves tested and how

4 in the centre wing box in the feed lines to 1,2,3,4 respectively. It is a ball valve with TMA same as LP valve.

61. How many valves in the crossfeed system and where and what type is it

Manually or automatically.

62. How are they controlled

Micro switches on the shaft (so the actuator NOT the valve)

63. Where is the position sent from for the LP and crossfeed valves

Only a backup for hydraulic cooling if air/hyd fails. In the Lower skin of each wing enclosed by outer engine pylon

64. What is the Heat exchanger purpose and location

Fuel diffuser (outside collector cell) and fuel returned to below fuel surface

65. How is the heat exchanger fire proofed and where

TMA yawn. On front spar

66. What is the heat exchanger isolation valve

HSMUs request to FQMS who make decision

67. What is the logic path for Heat exchanger ops


68. What is the max temperature allowed for the fuel in the Heat exchanger

DC 1 and DC ESS

69. What are the power supplies

DC ESS powers each Motor 1 closed

70. What happen in Electrical Emergency Configuration

Every flight 120s after ‘On Ground’ recieved. This also prevents trapped fuel in exchanger

71. When is the heat exchanger valves tested

From ENG 4 fuel feed via Isolation Vlv and APU LP vlv using engine supply pump or APU pump

72. How is APU fuel supplied

Rear Spar ribs 14+15 (mid tank area)

73. Where is the APU fuel pump

Thermal relief valve (part of bypass valve) releases over pressure to inner tank,

74. How is APU fuel line proctected

Ball valve SMA on rear spar of centre wing area

75. APU isolation valve is where and what type

Ball valve TMA, to isolate feed pipe in case of fire etc. In the unpressurised area frame 112

76. APU LP valve location, purpose and type

Flight deck switch to ECB (or bleed sw fwd of APU fire bulkhead) send demand and valves open. If there is insufficient pressure from eng 4 feed line APU pump runs

77. Describe Fuel delivery Logic

Hold the Shut-off Test button for 5s

78. How do you test the refuel panel


79. What are the status Lines on the IRP


80. How many ways can you set the PFQ

Sets off, auto, manual, defuel, Transfer

81. What does the mode select sw do

If there is > 1000litres of fuel in a surge tank

82. When will the overflow light come on

Electrically controlled fuel operated

83. How are the refuel valves operated


84. What is IRP access door number

6m up, 3m from each engine

85. distance of refuel coupling

40psi with max 55psi. Max 2degs

86. What are the refuel pressures and a/c fueling angle

CG target using default values(272T 36.5%), or using specific values for ZFW and ZFCG via FMS, OIT, OMT, ACARS

87. What are the 2 methods of auto refuel

High level shut off operates or preselect qty +-400kgs. The END light comes on in Flt deck and then refuel P/B pressed to off

88. When is fuelling completed and what happens then if cockpit refuelling

3. Load Alleviation (to prevent structural stress on the ground and in flight), Main Transfer (to maintain fuel in feed tanks) and CG transfer

89. How many types of fuel transfer are there

Load Alleviation and CG only. Not Main whilst Load Alleviation is running

90. Which transfers can happen at the same time

Inner —> Outer, Mid —> Outer after T/O. Outer—>inner, Outer —> Mid, then to feed tanks, Trim —> inner, Trim —> Mid, Trim to Feed tanks before Landing

91. What is the Load Alleviation Transfer sequence

Only after Load Alleviation finishes —> Inner —> feed tanks, Mid —> feed tanks, Trim to feed tanks, Outer —> Feed Tanks

92. What is the Main Transfer sequence

If the fuel temp drops to -35degsC and any feed tank has less than 18T (all other transfers are stopped)

93. When are Outer tanks emptied in flight

Trim —> Inner, Trim —> Mid, Trim —> Feed Tanks

94. What is the CG transfer sequence

10. 1 outer, 2 mid, 2 inner per wing. 115VAC 3 phase rectified and regulated to DC. A DC brushless motor

95. How many Transfer Pumps are there and where. And what type

Pressure switches on rear spar break contact between 5.5->65.psi an remake 4.5->5.5pis

96. How is the transfer pressure controlled

Via fwd transfer gallery or aft if fwd u/s

97. How is the fuel moved

SMA ball valves

98. What type are the transfer valves and where are they

Used a transfer defuel valve in the centre wing box to connect the crossfeed gallery with the refuel gallery

99. Where else is this transfer valve used

A TMA transfer valve and pipe at front spar of surge tank between outer and feed tank 1/4 to gravity feed fuel. Uses red guarded OUTR TK EMER XFR P/BSW

100. What is used to improve fuel availability after UERF event

4 total. Aft transfer gallery between ribs 1,2 and ribs 34,35. Fwd transfer gallery ribs 5,6 and ribs 35,36. Its a spring loaded valve and discharges into the fuel tanks

101. Describe Surge pressure relief valve type and location

2 on fwd spar L/R. 115vac 3 phase.with px sw

102. Trim tank Transfer pump type and location

Via 2 transfer isolation valve to fwd and aft gallery. SMA ball valve

103. How does the trim tank transfer connect to the main transfer system and what sort is it

3 ways. FQMS auto, Cockpit and IRP manual

104. How is the transfer system controlled

OPEN in the switch (which means NOT closed) and double green arrows with the word JETTISON. If active but valves closed its Amber

105. What are the jettison on indications

An anti corona device on flap track fairing 5. Valve is ball type TMA

106. Describe type and location of Jett Nozzle and actuator

Any FQI fail or Electrical Emergency Config

107. When will the fuel Jett not work

CPIOM-F, TSPs and probes. Secondary is the AGP software hosted in the FQDCs and talk to CDS via ARINC 429 via IOMs

108. What are the primary and secondary systems of the FQMS


109. What are the power sources for FQMS

Interacts with CPIOM-E for bus bar info incase emergency configuration is needed

110. What other CPIOMs does the FQMS interact with and why

HSMU for heat exchangers. LGERS for on ground (from L/G lever UP). ADIRS 1 and 3 is primary for air reference. ADIRS 2 is secondary. FADEC, APU, Auto Flight (for CofG etc), Flight control (CofG etc). NSS

111. What else does it connect to

Fire Protection

3 zones and one pylon. Z1 = Fan 2 pairs of det. Z2 = intermediate compressor 1 pair of Det, Z3 = Core 1 pair of Det

1. What is monitored on Trent 900

The core (2 pairs of det in fan exhaust cowls) and each pylon.

2. What is monitored on GP7200

1 FDU (Fire Protection Unit) for the engines, APU(1 pair of det) and MLG (R and L WLG, R and L BLG 1 pair each)

3. What takes care of the fires protection system


4. What powers the APU and ENG squibs

Electro-pneumatic. A sensing element (made of a hydrogen charged core surrounded by helium) and a responder assy.(made of s/s. Has 2 pressure switches (integrity and alarm) giving Normal Fault or Fire) Responder sends to FPU via conversion module. 2 loops A + B

5. What is the technology of the fire detectors

Integrity closed if good. Alarm open if good.

6. How do the switches of the detectors work

Batteries only.

7. When does only half the LEDs of the Fire P/B come on

To extinguish the fire in the nacelles and to prevent fire extension by cutting it off

8. What are the 2 main functions of the fire extinguishing system

It is a High Rate Discharge system using Halon 1301.

9. What is the engine fire extinguishing

In a pressurised area

10. Where is the APU conversion module

2 continuous loops in parallel and use AND logic

11. How are the MLG and APU loop connected

Loop A to channel A (and B to B) of Conversion module. Engines to all 4 channels (Ch1=1+4,Ch2=2+1,Ch3=3+2,Ch4=4+3), APU to channel 1 + 2 of FDU. MLG to channel 3 +4. Uses Can bus

12. Which channel of the FDU do things go to and what data type

Temperature Compensated Pressures Switch (TCPS) on each fire bottle to each channel except APU channel A only

13. What else is sent to the channels

Main Avionic Bay. 4 Channels and a BITE card connected to each channel. LGERS, ICP TEST switches, The conversion modules

14. Where is the FPU, How many channels, What else and what talks to it

A+B fail within 5s

15. When is a fault declared a fire

Rear of pylon secondary structure. I/b and o/b are different

16. Where are the engine fire bottles and are they the same

CRC continues receptive chime

17. What is the fire warning sound

5. Avionics, Cargo Compartments, Toilets, Cabin sub compartments, additional electronics compartment

18. How many areas have smoke detection and what are they

Arranged in pairs. Only toilet bins, cargo and LD crew rest have extinguishing built in. The others have portable bottles.

19. How is the detection arranged and is there any fire extinguishing

3 SDFs in CIDS. Uses CAN BUS (segregated into A B C D). CIDS talks to FWS and CMS via AFDX. Also talks to VCS via AFDX to shut off ventilation as appropriate

20. What looks after these software wise and how is info sent and to where

They are in FWD cargo. A flow metered bottle(2 the small one) (240mins) and a high rated bottle (1 the large one). Power supplies are DC 2 and DC ESS to squibs A + B. Have TCPS

21. Where and how many and what power for cargo bottles and what is fine to them

CARGO overhead CARGO SMOKE panel, AVNCS p/b on VENT panel, IFEC p/b on ENTERTAINMENT panel

22. Where can warnings be seen

Main and emergency by 2 pairs, rear by 1 pair IFEC by 1 pair

23. How are the avionics and IFEC monitored

4 pairs of detector fwd and aft, 1 pair in bulk

24. How is cargo monitored

1 pair SMK DET each. Goes to FAP to show warning an alert can be reset. VCS stop ventilation if in vented area

25. How are lavs, upper deck social, stair house and stowage compartments monitored (cabin sub compartments) and what is seen

Cargo Smoke panel in FD, 2 Fire Extinguishing Data Converters to monitor and fire squibs, 2 bottles of halon 1301, 4 nozzles fwd and 5 aft/bulk, Flow metering to keep going (240mins), diverter valve

26. Describe Cargo fire extinguishing

Pairs of Duct type SMK DET in air extraction ducts

27. Describe smoke detection in Avionics and IFEC

Buses C and D talk to Main avionics and Emergency Avionics (inclusion NSS bay) and IFEC. A + B do aft avionics

28. How does the data transfer work for CIDS and SMK DET

2 Bottles (1 discharge 1 metered) controlled from staircase housing FES panel. Fire Extinguishing Data Converter (FEDC) controls and monitors squibs. 3 nozzles in ceiling

29. What looks after the fire extinguishing of the Lower Deck Cabin Crew Rest

Ambient type Smoke Detector in the air outlet cavity, DEU-B and CIDS SDF. DEU-B send to CIDS SDF if smoke detected. FAP and EWD display, DEU-A sounds cabin alarm

30. What is involved in the lavatory smoke detection


31. What temperature does the Fusible plug melt on toilet bin extinguisher

Photoelectric cell comprising of thermal and hygrometry sensors.

32. What is the technology in the smoke detectors

COND on ECAM. EWD shows actions to take

33. What page is automatically displayed on CDS for Cargo or Avionics bay or IFEC smoke

Push button on cargo smoke panel. Tests all avionic bays. COND page shows and all isolation valves can be seen to close

34. How is the smoke test actioned and what does it test


2 G/b. APU load G/B = 2 GENs + oil pump, and Accessory G/B driven by starter + has eng oil pumps

1. How many gearboxes and what do they do

Both systems share a single tank with a shared filler cap and vent and with a compartment each. The generator section fills first and then flows over to the main engine section. The Eng section has a long sight glass and the generator section has a bullseye

2. How is oil stored and measured

It is within the Load G/B. It is referred to as a Hot Tank Type

3. Where is the APU oil tank and what is its type

In the Accessory G/B and vented to exhaust duct

4. Where is the air/oil separator

Total = 18.9 ltrs, Main = 13.7 ltrs, Gen = 5.1 ltrs

5. What is the oil capacity

The Generator side fills first and then a float valve closes and the main side begins to fill until its float valve closes too.

6. How is it filled

APU P/B in FD, FIRE P/B in FD, NLG and IRP

7. Where are the various ways of shut down APU


8. What monitors the APU

3 shock mounts, 2 FWD on top of Load G/B and 2 AFT on gas generator case aft of fuel manifold to a single mount by links

9. How many mounts on APU, what type and where and how

Air Cooled Oil Cooler (ACOC) in educator assy

10. How is the oil cooled

At the beginning of each start cycle by monitoring bullseye sight-glass

11. When does ECB measure oil qty and using what

Approx 60hrs above ADD, then another when ADD is reached which is 60hrs before minimum

12. What oil level signals are sent

ECB energise FCU sol vlv. Fuel Px opens FCU S/O vlv. Fuel flows thru FCU to flow divider. Fuel Px overcomes flow divider dump vlv spring. Fuel flows to primary nozzles. At some Px the flow divider allows flow to secondary nozzles.

13. Describe the start sequence fuel-wise

ECB controls FCU torque motor.

14. How is fuel metered during operation

14 primary, 14 secondary

15. How many fuel nozzles

The IGV actuator and the Surge Control Valve. Regulated by FCU

16. What else is fuel pressure used for and how is it regulated

A dump valve to send vaporised fuel into the exhaust flow

17. What else does the divider valve have

Bleed vlv, Surge Control Vlv, IGVA, Load Compressor Delta px sensor and static px sensor and the APU eductor assy

18. What makes up the APU bleed air system

Butterfly. Bleed has open/closed switches, Surge Control has LVDT and is adjusted by Load Compressor static and delta px.

19. What type of Valve are the Bleed Valve and SCV

CPIOM A for PADS to give the Bleed valve closed etc

20. What systems does the ECB talk to

Fuel on, Flap open. Starter on, IGV to 47%, SCV open. N2 = 8% fuel and ignitors. N2 = 40% starter and ignition off. N2 = 55% IGVs to min. N2 = 86%(at no load) N1 = 95% for 2s “APU AVAIL”

21. What is the APU start sequence

De energise the FCU shutdown solenoid

22. How is protective shutdown achieved

No cooldown cycle

23. How does protective shutdown differ from a normal shutdown

In flight oil faults, EGT o/temp N! Underdspeed and surge faults are ignored

24. Are the protective shutdowns the same in flight and on GND