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Primary (pylon box) and Secondary Structure (front and rear) with its fairings. Primary carries mechanical loads, secondary has equipment. Pylon also has aft pylon fairing called lower fairing

1. Describe the pylon

3 mounts. Forward ( on fan hub. Vertical and side loads), aft (On turbine exhaust case. Vertical, side and torsional) and strut ( X 2 each side of Fan Hub. thrust loads)

2. Describe the engine mounts

2 components. Shackle and Mount beam

3. Describe front mount

4 components. Monolythic Mount beam, 2 Boomerangs and 1 central link

4. describe aft mount

3 components. 2 connecting rods and 1 cross beam. It remains with engine for QEC

5. Describe strut mount

Fail-safe or Dual load path with spherical bearing. Allows for axial thermal expansion and some movement between engine and pylon.

6. What type of mount is an engine mount

LHS pneumatic and electrical. RHS Fuel/ Hydraulic and VFG feeder cables. On front secondary are FADEC on RHS and Hyd on LHS

7. Describe the connections

Fan to pylon secondary, Exhaust to pylon primary

8. How are Fan and Exhaust cowls fitted

Air intake has fan cowl switches, Antice outlet and antice access panel. L Fan Cowl has oil tank access and 1 vent inlet. I/b exhaust has 3 thrust reverser actuator access panels.

9. Whats on nacelle LHS

Air intake has fan cowl sw and T12 access panel and I/p jack. R Fan Cowl has vent inlet. R exhaust has 3 reverse thrust actuator access.

10. Whats on nacelle RHS

Slats retracted and locked out. Elec power avail. Open latch access (later engines only) and 4 latches 4-1-3-2 (back/front back/front). 40-49 degs is temp pos only. < 49 is red > 49 is green

11. Describe Fan Cowl opening including the opening positions

Cascade type with translating cowls and blocker doors. 4 hinges, 2 are attached to floating rods.

12. Describe T/R and the Cowl hinges

on the exhaust cowl

13. Where is the fire loop

Latches L1 to L7. Opened using COS Power Unit to convert AC to 270VDC. L2,3,4 in latch access door.

14. Describe Thrust Rev Cowl opening


2 rotors. LP (24 blade Fan and 5 stage comp, 6 stage Turbine. Roller bearing at second stage of comp Ball at last stage of LPC and roller at rear end.) and HP (9 stage comp, 2 stage turbine. Ball and roller at front, Roller at rear) on 6 bearings. Both rotate Clockwise VFR. F5926

1. Describe the Engine

Bevel Gear Assy (in Fan hub frame), Lower bevel gear, Verticle Tower Shaft, Angle GB, GB drive shaft and main GB.

2. Describe the Accessory GB drive

Below HPC case. Has 6 point mount system.

3. Where is the Main GB mounted and how many mounts has it got

EDPs, Lubrication and scavenge oil pump, PMA, De-oiler and Manual crank pad.

4. What is on the front face of AGB

VFG Starter Main Fuel Pump.

5. What is in the rear face

Main oil filter Fuel filter FMU Servo fuel heater.

6. What is also in AGB but not driven

2.0=Core Inlet. 2.5=HPC inlet. 3.0= HPC exit. 4.6=LPT 2nd stage. 12.0=Fan inlet

7. What are the gas path stations

1 roller (gives radial support to LP fan Frame), 2 ball (radial and axial to LP fan Frame), 3/3 roller/ball (HP rotor support. Front of HP. Fan frame. Roller is oil damped), 4 roller (radial to HP, turbine centre frame), 5 roller (LP radial turbine ex case)

8. Describe the bearings


Fuel filter and clogging delta px sw, Filter, MFP (2 pumps oil line ), FMU, Main FOHE and Servo Fuel Heater, Servo Valve ASSY.

1. What are the main parts of the fuel system

Main supply to Fuel pump Boost stage. Then to FOHE. Then to strainer and to FP gear stage. Then to High PX filter. (Gear stage protected by o/px relief which returns fuel to inlet of gear stage). Then to FMU and a small amount to wash servo filter. In FMU fuel accross EEC controlled metering valves. And also Px and SO Valve (connected to MASTER LEVER and EEC) and to manifold

2. What is the fuel flow


3. How many fuel nozzles

Some fuel doesn’t go to FMU but goes to servo fuel heater for SVA and HPT ACC valve actuator, Start bleed valve actuator LPT ACC and FMU metering Valve servo valve and FMU PC regulator

4. Describe the fuel servo parts

The failsafe is LPT ACC, HPT ACC, and Start Bleed valve actuators.

5. Which valves are biased closed in the event of Servo Valve Assy failure



1. Describe the FADEC

EEC is A/C power via EIPM until N2 > 12% then PMA (12.5% accel, 10.5% decel). EMER BUS to CHA and NORM BUS to CHB. VMU is A/C 115V from EIPM

2. What powers the EEC and VMU

A429 to EIPM from CHA

3. How is EEC data path backed up

From TRA analogue signals from dedicated resolvers independent of the ACDN

4. How is throttle pos received

Hard wired to EEC

5. How is A/THR instinctive disconnect connected

Separately Hard wired to CHA and B of EEC for reset and for AFDX failure

6. How is MASTER LEVER connected to EEC


7. What else is the MASTER LEVER hard wired to


8. What lights the fault light of MASTER level

AICU to EEC <————— check this!

9. What sends Antice command

In ENG order 1234 = 2B,1A,2A,1B (2121 BAAB not ABBA!!!!) IOMs are 56/12/56/12

10. How are EECs, IOM, and EIPMs connected

ENG 1234 = 2A1A2B1B (2121 AABB)

11. How are AICUs connected to eng

The electrical power to EEC, COS, ETRAC, VMU and Exciters

12. What does EIPM control and monitor

From a Discrete Signal Input group the EIPM generates Discrete Signal Output group for A/C interface.It also exchanges A429 for the usual OMS shit

13. What are the data connections

28VDC normal bus.

14. What powers EIPM

Gives 2 indépendant 3 phase power to CHA and B. 1 phase is dedicated to N2 sensing

15. Describe PMA

For 15 mins after A/C power up. START Sw to Crank or IGN/START. MASTER Lever to ON. On GND moving it to OFF removes the power after 15mins. Using ENG FADEC GND PWR P/B which auto turns off after 10mins not being used.

16. When is EEC powered

On GND only if MASTER LEVER off and START in NORM and GND FADEC off. In air and on GND the fire handle kills power to EEC

17. How do turn off EEC straight away

A/C power is avail for EEC and VMU

18. What if EIPM fails

If 1 winding fails EEC will change channel. If both fail EIPM will use airframe

19. What happens if PMA fails

PMA(7 O’clock on AGB). SVA Compressor Case 12 O’clock. 4(of 8) x T4.6 EGT probes in LPT case 7,8,9,11 O’clock. P/T2.5 Px/T sensor on FHF 8 O’clock. T3 Temp on Combustion case at 8 O’clock. N1 sp sensor FHF 7 o’clock. N2 sp sensor Angle GB 6:30 o’clock. PS12 sensor at Fan Case 11 o’clock.

20. What is on LHS of engine

Fixed setting using fusible links and user programmable using push pull pins.

21. What makes up the Data Entry Plug (DEP)

During each GND power up it is read into EEC non volatile memory. If it fails it uses defaults. But will be nil dispatch

22. How does EEC use the DEP

Sub idle on ground only.

23. When does FADEC protect against EGT exceedance

TCMA(Thrust Control Malfunction Accommodation) and EOS (Electronic Overspeed System)

24. What are the limit and protection sub systems

Shuts off fuel using FMU HPSOV. Dual wound torque Motors (CHA & B). Monitors N1. TCMA in either CHA or B (regardless which is stby) can initialise a cut back or a shutdown. Inactive above 15000ft or over Mach 0.40. Calcs N1 overspeed but 110% is max. Needs N1, Mach and Alt or it’s a No Go. I/Ps, cut back and Shut down tested during GND start

25. How does TCMA work and when

If Engine Overspeed detected uses FMU HPSOV to shut off fuel engine. It is a separate self contained circuit card called General Purpose Board. Once active remains in shutoff until metering vlv closes. BITE during ENG start. 1 CH is dispatchable, 2 are not

26. How does EOC work and when

Starting and Indications

EIPM using date from EEC.

1. What lights the FAULT light on MASTER Lever

THR, N1(LP Fan speed) , EGT

2. What ENG Params are on EWD

Using ACUTE ( Airbus Cockpit Universal Thrust Emulator ) 100% is max thrust with bleed off in TOGA

3. How is THR calculated


4. How do you see Secondary Eng Indication

N2, FF, Oil qty, Oil PX, Oil T, VIB N1, VIB N2 and NAC (replaced with start params during start).

5. What are the secondary Params


6. What extra is on the cruise page


7. What are the the Throttle positions

On the EWD as a little cyan circle on the THR ind.

8. How can you see the throttle movement

It is at the top of the EWD

9. How do you now the THR mode

Direct to EEC

10. How are the instinctive disconnect buttons connected

To sense commands and generate electrical signals

11. What is the primary function of TCA

4 independent groups of 2 resolvers and 3 pots. T/R is by sw through pots. 1 per lever.

12. What are the Throttle Control Lever Sensing Devices composed of

0 stop. IDLE REV detent, MAX REV stop

13. What are the stops of the REV THR

Between the pylon air duct and starter duct.

14. Where is the starter stub duct

Left side of combuster diffuser nozzle 10->7 o’clock pos.

15. Where is the starter air supply duct

Vlv is on starter at 6 o’clock pos. Sensor is on vlv

16. Where are the starter Air Vlv and starter Air PX sensor

58.4% N2

17. When will the starter air valve close

Aft face of AGB at 6 o’clock

18. Where is the starter and how is it attached

Either channel can control either or both ignitors

19. How are igniters controlled by EEC

A/C normal or Emergency. 115V managed by EIPM

20. What is the ignitor Powe supply

On SD page replacing NAC. It is IGN A and/or B , PSI of starter and SAV pos

21. Where is the starting sequence visible

MASTER lever OFF. ENG START to NORM. MAN start not illuminated. ENG START to START. ECAM is displayed and AGU FCV closes. ENG MAN to ON, SAV opens. At N2 20% MASTER on. A and B IGN begin LP and PRSOV open. FF increases. Within 30S EGT rises(max 745). At 55.7% IGN stops. At 58.4% SAV closes. MAN to OFF. START to NORM. AGU reopens and ECAM ENGINE page goes.

22. What is the manual start procedure

Dry crank for 30s (5mins max) for cooling.

23. If MAN START fails what must you do

30s to 5mins max

24. How long can you dry crank for

ECAM Eng page appears

25. What happens when you put the ENG START sw to CRANK

ECAM Eng page disappears

26. What happens when you put the ENG START sw to NORM

Set ENG MASTER to ON @ N2=15% for 15s then to OFF. After the wet CRANK a 10 minute ‘Bake Run @ idle must be carried out

27. Difference between wet and dry CRANK


Manual starts, Auto restarts and in-flight starts

1. When are both ignitors A and B used


2. How do you select continuous ignition

115VAC from EIPM and EEC

3. How are ignitors powered

CHA->1, CHB->1, CHA->2, CHB->2

4. How are ignitor starts sequenced

Engine Cooling and Sealing

It is the ACC (Active Cooling Control) system consisting of HPTACC and LPTACC (High/Low Pressure Turbine Active Clearance Control)

1. Describe the Engine cooling and sealing system

Fan air

2. What air does ACC use

EEC controls SVA (Servo Valve Assy) that operate HPTACC and LPTACC actuators air valves. The actuators feedback to EEC

3. How is it commanded

Compressor air control

2.5 Bleed system, The start bleed system, The compressor stator vane control.

1. What does the Airflow Control consist of

Controls LP compressor operating line to provide optimum LP performance and prevention stalls using 5th stage LP compressor air. Attached to FHF at 11 o’clock

2. Describe the 2.5 bleed sys

Open at shutdown and gradually becomes completely closed at TO power. Open for rev thrust and low power icing and decent to reduce FOD damage

3. When is the 2.5 Bleed open and closed

Release 7th stage air of HP comp to give additional stall margin during start. EEC controls best position. Attached to Air duct aft of HF at 12 o’clock

4. Describe the Start Bleed System

Open only during start as determined by EEC. Spring biased closed by fuel px.(along with LPT and HPT ACC vlvs)

5. When is the Start Bleed System valve open and closed


6. What is the feedback of the start bleed sys

Operates VIGV/VSV actuation to vary angle-of-attack for first 4 stage of HP compressor. (First 4 being IGV to 3rd stage!!)

7. Describe compressor stator vane control

to the SVA(servo vlv assy)

8. Where does EEC send it demands

N2 and T25 I/Ps

9. How does EEC calc VSV position

A single LVDT on actuator. Left(CHA) is at 2 o’clock and right (CHB) at 7 o’clock

10. What is the feed back of the VSV


11. What is the fail safe

Thrust Control

From AFS, TCA, KCCU enters TO data.

1. How does EEC decide thrust

Transitive mode between A/T and manual. Prevents sudden Thrust changes by using last known N1 ACTUAL

2. What is MEMO Thrust mode

When EEC can’t tell ambient conditions from ADIRU(PS PT TAT ) and engine sensors (P0 P12 T12 ) fro 2s or more

3. Describe N1 degraded mode


4. What is the N1 degraded indication

It remains Latched in N1 degraded mode

5. What happens if the conditions for N1 degraded are no longer applicable

Usually engine params are compared to ADIRU params via AFDX. Ps to P0, Pt to P12 and TAT to T12

6. How are the sensors compared

7 sources… 4 EECs and 3 ADIRUs used to compare and set N1

7. How many sources are there in total


8. What decides the A/THR logic


9. What states can A/THR be in

Throttles control thrust.

10. What if all Throttles are above CL with 4 eng

The detent position of the Thrust Lever. (Usually the highest)

11. What determines the thrust limit mode

The little cyan circle representing the throttle pos

12. What is THR REF

The PRIMs throttle request represented by a thin green lion

13. What is THR CMD

The actual current Thrust represented by a thick green lion

14. What is THR ACT

MASTER lever

LP vlv and MPSOV

1. What does the ML affect in the Fuel system

Sets starting mode and does reset

2. What dose the ML do to the EEC

Hardwired to HMU

3. How does control MPSOV

Via switch slave relay (for 60s only)

4. How does it control LP VLV and for how long

Hard wired to each channel. Each CH also tells the other CH. It is also hard wired to IOM to EEC

5. How is it connected to EEC

If MPSOV pos disagreed with ML pos and also for start faults. It is managed by EIPM looking at data from EEC via IOM

6. When does the ML FAULT light come on

Dual prox sensor

7. How is MPSOV determined

Thrust Reverse

PRIMs for TLS, EIPM for TRPU power (270VDC) and DEPLOY/STOW from EEC to ETRAC

1. What commands the 3 lines of defence

Electronic Thrust Reverser Actuation Controller. On right hand T/R cowl 3 o’clock

2. Where is the ETRAC

Thrust Reverser Power Unit. RHS T/R cowl 4 o’clock

3. Where is the TRPU

RHS 1 o’clock

4. Where is the PDU

Prevents overspeed if motor control lost

5. What does PDU brake do

LHS T/R cowl 6 o’clock

6. Where is the TLS

270VDC from ETRAC does RH lock. TRPU does the LH

7. Where do the PLS unlock signals come from and how

It is energised

8. How is the PDU brake released

Middle actuator has MDU (manual drive device)

9. Where is the access to manual open T/R

2 resolver sensors on lower actuators

10. How is T/R pos monitored


11. What are the rev Throttle positions for T/R action

Oil System

1 lube 5 scavenge

1. Describe the oil pump

325-400psi. At 325 it begins to return to inlet

2. What is the lube pump discharge px

Dual element main filter

3. Wheres is go after Pump

Grouped into 3 sumps. A, B, C. 123, 4, 5 (3 is actually 2 bearings)

4. How are Bearings lubed

Dampens bearings 3 and 4

5. What does the modulation valve do

Before each bearing sump

6. Where are the last chance oil strainers

It is on the Oil Flow Management Valve. Reports to EEC CHA and CHB

7. Where is the low oil px switch and what does it report to


8. Which bearing sump has 2 scavenge pumps

123 sump, angle GB sump/Main GB sump, 5 sump

9. What are the other scavenge pumps on


10. Where does the oil debris monitor send its info

123 (via vent tube) and MGB to de oiler. 4,5 and Angle GB is returned to oil tank air/oil separator with scavenge oil

11. How is breather air routed


12. What is the tank breather px max