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Rolls Royce RB211 TRENT 900

Engine Makeup

Primary structure (called pylon box).Carries the mechanical loads. The secondary structure. Has space fairings and space for component. Also has aft pylon fairing

1. Describe the pylon structure and what each part does

3 mount assy. Fwd mount attached to intermediate case and carries vertical and side loads. Aft mount attached to tail support and carries vertical, side and torsion loads. 2 Strut mount left and right each side of intermediate case for engine thrust

2. Describe the engine mounts

Left side for secondary pneumatic and electrical, right side fuel and hydraulic. Below are pneumatic

3. How are things connected from engine to pylon

Fan cowl switches and inter phone jack

4. What access is on the left air intake

Starter valve manual override

5. What is on the left fan cowl

3 accesses for thrust reverser actuators

6. What is on the left fan exhaust

Fan cowl switches and P20/T20 probe access

7. What access is on the right air intake

Oil access, fan cowl latches

8. What is on the right fan cowl

Latch access/blow out door and 3 accesses for thrust reverser actuators

9. What is on the right fan exhaust

4132 (back/front back/front)

10. What is the fan cowl latch opening sequence

Wind speed < 45knots, Slats retracted and locked out

11. What must be considered before opening

2314. (Inner front/back, outer front/back)

12. What order are the latches for closing

40degs locked = intermediate no indication as does 40->50degs, red unlocked, green locked at 50degs

13. What do HORs tell you

The thrust reverser has an 8th latch which must be opened first and closed last

14. What about latches specific to engine 2 and 3

(8), 1, 6.1(does 7), 6.2, 5.2, 5.1, 4, 3, 2 --->(1,6,5,4,3,2)

15. What is the sequence for unlocking exhaust/thrust reverser cowl


16. What is the sequence for closing exhaust/thrust reverser cowl

3 rotors. LP (1-5) 3 bearings RBR CCW , IP (8-1) 3 bearings RBR CCW, HP(6-1) 2 bearings BR CW. (1,8,6 5,1,1)

17. How many rotors, bearings and rotation


18. How many fan blades

Also called location bearing. Support axial and radial

19. What do ball bearings do

Support radial and allow for axial thermal expansion

20. What do roller bearings do


HP to Internal GB, Radial shaft, Intermeadiate GB, external GB driveshaft, Transfer Box and AGB

1. How is the accessory drive driven

Ded gen, Starter, Hyd pumps

2. What is on the front face of the AGB

VFG, oil pump, breather, fuel pump, HMU

3. What is on the back face of GAB

By hydraulics only

4. How is the HMU driven

Fuel manifold and HMU

5. What is on the RHS of AGB

IP8 air to labyrinth seals

6. How is it sealed

0 (intake, fan in) 20, 24(iP in) 25(HP in), 30 (HP exit), 40(combustion exit), 50 (LP exit) , 160 (fan stream)

7. List the aerodynamic stations

Metered for combustion, cooling oils, powering servos for actuators

8. What things is fuel used for

HMU and fuel pump.

9. What are the main components of the fuel system

3. Low Press pump (LPP) single stage centrifugal, Main High Pump (Main HPP) spur gear and feeds HMU, Servo High Pressure Pump (Servo HPP) spur gear feed to HMU to drive VSV.

10. How many pumps in fuel pump and what are they

They are combined in a single unit on the rear face of the AGB

11. Where are the pumps

LPP around 175psid max main HPP increases it to 1720psid. Servo HPP is 1825psid

12. What are the pump pressures

HPP pumps 2250 and 2350psid

13. When do the relief valves operate

LP at exit from fuel tank, HP in HMU

14. Where are the LP and HP shutoffs

EEC can shut HP, Master sw closes both

15. Who closes the HP and LP

40 micron with diff press transducer set at 5psid. Bypass at 25psid

16. Describe the LP filter

In the inlet to fuel manifold. 250micron cleanable.

17. Describe the HP filter

Flexible hoses at equal distance around combustion outer case to 20FSNs

18. Describe the fuel manifold and nozzles

RHS of fan case below oil tank

19. Where is the FOHE

LPP pump and include the LP filter which is sealed by a spring loaded pressure plate reacting against the filter housing end cap bolted in to position

20. Where’s the fuel come from and how is it protected

4. Fuel Metering, Overspeed protection, Fuel High Px control, VSVA control

21. How many servo valve torque motors in HMU and what are they for


22. What control the HMU servo valves

The constant pressure drop principle. It varies bypass return flow back to HP inlet . PRV maintains a constant pressure drop across metering valve

23. On what principle does the HMU operate


24. How is metering Valve position known

Airframe Shutdown Solenoid is energised. Pressure drops at the PRV and Minimum Pressure & SOV (MPSOV) closes by spring.

25. What happens with MASTER sw off

Dual proximity probe

26. How is MPSOV position fed to EEC

Normal shutdown, N1 or N2 overspeed, LP turbine Overspeed, Thrust Control Malfunction (TCM)

27. When is the protection torque motor operated

TCM during start, Overspeed during shutdown.

28. When are TCM and Overspeed BITES carried out

PRIM needs to ok shutdown otherwise just reduced fuel flow.

29. What gives shutdown permission during a TCM and what happens during a TCM without permission


EEC and EMU on left side of fan case 10oClock position

1. What makes up the FADEC and where is it

2 channels A and B. 2 PSU PX sensors etc. Talks to ADCN for ADIRU etc

2. What makes up the EEC and what does talk to

17 electrical receptacles (9A 8B). THE Data Entry Plug (DEB) is on the B side but on top.

3. What are the connections

Yellow stripe for A. Green stripes for B

4. How are the channel harnesses identified

One is control the other stby

5. How do EEC ch A and B work together

Engine Interface Power Management. Delivers A/C power to the EEC EMU and engine. Avionic bay

6. What is the EIPM and where is it

EIPM 1 for ENG 2+4 and EIPM 2 for ENG 1+3

7. How are EIPMs organised

28VDC DC1 but provides 115VAC from aircraft to EEC

8. What is the EIPM power supply

PMA normally or EIPM if unavailable(< 8%N3 or u/s) (emergency bus 115v AC CH A. AC2 for CH B). EMU by 115V A/C power.

9. How is EEC and EMU normally powered

Stator and rotor independent 3 phase generator. N3 > 8% the EEC shares this and A/C power. One phase is just for N3 sensing

10. Describe the PMA

Dual channel memory device (EEPROM) that stores the engines particular data and gives it to each. EEC channel on Start up. Engine S/N, ratings EGT trim, Idle trim etc

11. Describe the DEP

LP and IP have 60 tooth phonic wheels. LP at rear of roller bearing case, IP on compressor front stub shaft. 4 speed probes each shaft in relevant bearing housing (2 probes to each channel). HP uses Dedicated Alternator frequency from 2 separate windings for A and B

12. How are the shaft speeds measured

The book doesn’t say!) to right of TDC. Measures intake Px and Temp.

13. Describe P20/T20 probe and location? 15degs (or 150mm or feet or inches

Using 2 independent platinum resistant elements.

14. How does P20/T20 measure Temperature

Via a pipe to a single sensor in the EEC CH A which kindly allows B to have it to. It is noise filtered so as no to hurt the poor lil EEC

15. How is P20/T20 pressure supplied to EEC and anything special about it

115V. EEC determines based on A/C in flight and N1>10%, On GND with N3>45% and N1>10%. Any other time it is off

16. What is the P20/T20 heater supply and how is it triggred

Inlet to LP turbine (T44) LP1 NGV. Uses 14 thermocouples connected in parallel in 2 groups of 7. Left group to CH A right group to CH B

17. Where is EGT measured and how and where is data sent

2 sheathed elements (Chromel and Alumel) at different depths to a common pair of terminals. Connect to EEC via terminal block

18. What is the make up the EGT thermocouple and how do they connect to EEC

As a parameter for TPR for monitoring and FD indication

19. What is EGT used for

IGN selected EEC and EMU powered. When in NORM EECs powered, EMUs off. With MASTER on EEC and EMU powered for 15 mins only. FADEC GND PWR P/B ON powered for 10mins if not put into interactive mode. ENG RUNNING… Fire push button kills all power instantly. If EIPM fails 115V from A/C will be avail at all times. If one PMA winding fails the other CH operates. If both fail a/c wiring takes over via EIPM

20. How is the FADEC powered in different scenarios? FOR ENG NOT RUNNING… At A/C Start up ChA from Emergency Bus, CHB from AC2 for 15mins. When CRANK or STAR

LP,IP o/speed (monitors N1&N2 shaft speed) auto shut down.. LP Turbine o/speed (duh). TCM. EEC monitors ENG Thrust and N1 speed. Will either reduce power or shutdown if PRIM signal permits

21. What protections does the EEC provide

A Programmable Logic Array is used. Needs both channels PLA to close its enable switches before the protection operates. (Unless on only one channel working the only 1 needed)

22. What is the protection Logic


23. What are the main Engine Primary Indications

N2, N3 F/F, Oil Qty, Oil Px, Oil Temp, VIB N1, N2, N3, NAC Temp. On engine or Cruise page

24. What are the secondary Indications and what pages

NAC Temp is replaced by Starting Parameters

25. What is replaced by what during ENG START

FF, Fuel Used, APU and ENG fuel consumption (T. FUEL USED) ENG consumption( all ENG)

26. What does the CRUISE Page show

Ratio of Combustion Chamber to intake pressure corrected by intake and turbine gas temperature

27. How is THR derived

As a % of THR available (FWD or RVRS)

28. How is THR expressed

ACUTE (Airbus Cockpit Universal Thrust Emulator) It provides the indications of thrust, thrust selection (REF) and thrust mode to the pilots via the EWD

29. What is the EEC THR processing function called and what does it provide

Turbofan Power Ratio though this is not displayed in cockpit

30. What is the preliminary parameter for thrust indication

0(idle), CL (climb), FLX/MCT and TO/GA

31. What are the throttle detents

A cyan circle on THR gauge and THRUST MODE top with %

32. How is throttle position displayed on EWD

Idle to Climb

33. What is the A/Thrust range with 4 engines

Idle to FLX/MCT

34. What is the A/Thrust range with 4 engines

Anytime thrust levers are not at idle.

35. When are the Thrust reversers mechanically locked

To sense the commands and generate electric signals.

36. What is the primary function of theTCA

4 independent groups of ---> 2 resolvers and 3 potentiometers (8 + 12) and 2 switches for thrust reverse

37. What are the sensing devices


Auto or Manual GND start, ENG Crank, InFlight Start, Cont Ign, Auto relight.

1. What are the start sequences the EEC controls

Butterfly type, Electrically controlled (coil to EEC A and another to B) pneumatically operated. Lower left of compressor case

2. Describe the Starter Control Valve and where is it

IGN sys (A and/or B), Bleed pressure, SCV position

3. What is displayed for the engine start on the SD Engine Page

Master SW=OFF. ENG START=NORM. ENG START=IGN/START. (ECAM ENG page appears and AGU stops) MASTER=ON. LP VLV and SCV opens. At N3=25% and EGT<150 ignition starts, HP SOV opens, FF and EGT increases. Max EGT is 700degs. N3=48% SCV closes Ignitors stop, AGU starts again. ENG START=NORM (ECAM page goes)

4. What is the auto start procedure

Hot Start/Stall or Hung Start(EEC does shutdown and then dry crank until EGT < 150degs then tries again), No light up, locked N1, SCV fail. High N3.

5. What causes Auto start abort

Very similar to auto start except… Manual switch on… At N3=25% and EGT<150 Master=ON. A and B ignition ON. Start Chrono and <30s EGT increases to max 700degs at 48%. SCV closes and set MANUAL start to off. At N3=50% ENG start to NORM

6. How is manual start achieved


7. What is the dry crank procedure

5 mins in a 35 min period.

8. What is the starter time limit of motoring

Everything off engine wise. ENG START=CRANK. When N3=33% MASTER=ON. When done(obeying time limits) MASTER+OFF. After 30s MAN Start to OFF. Switches to normal

9. What is the wet crank procedure

Commanded valve positions and flow detection in the state air ducting detect this. Cabin bleed and cross flow close prevent starter overspeed.

10. What happens with a SCV that fails to close

Bleed Valves

Fan air (LP compressor)

1. What is the air for the TCC

3 IP bleed valves @ IP 8, 3 HP bleed valves @ HP3, 1 stage of IP VIGVs, 2 stages of IP VSVs.

2. What air flow system valves are controlled by the EEC

Protection against surge and stall

3. What do the bleed valves accomplish

VIGV/VSV control valve in the HMU, 2 VIGV/VSV acuators, a VIGV/VSV actuating mechanism

4. Describe the IP compressor VIGV/VSV components

IP shaft speed and acceleration, LP shaft speed, altitude and T20. EEC directs HP servo pressure from HMU

5. How is VSV scheduled

Extended at low speed and retract as IP shaft speed increases. They are at 3 and 9 o’clock on IP comp case. Left just above centreline, right just below. Connected by 3 o/p rods to the unison rings

6. What position is the actuator shaft at various speeds and where are the actuators and how are they connected

LVDT single channel. Left to Ch A Right to Ch B

7. How is position of the actuator shaft confirmed to the ECC and what channels

“Transient” for acceleration change, surges, reverse thrust etc. “Failsafe” if IP speed not avail is to use LP speed and bring engine to idle. If power fails then it retracts the actuators (High speed position) and allows eng ops to continue

8. What are the 2 control types

VIGVs and VSVs all open. Allows IP rotor to be turned manually.

9. What happens at shutdown

2 Bleed Valve Solenoid Units. Upper left and right of IP compressor case. Each uses HP3 air and 2 electrical connectors (CHA and CHB) Each solenoid is dual wound for CHA or CHB control.

10. How does the EEC control the bleed valves and where are they and how do they work

Eng. off = opened by spring pressure. Engine running = closed. HP3 Pressure is required to force them open.

11. What is the normal position for a Bleed Valve

By-pass duct

12. Where does bleed valve air go when open

EEC knows if continuity to solenoid is good but doesn’t know its position. It will show itself as.. Open When should be Closed = higher TGT (pilot will see and CMS too). Closed when should be Open = Hung/hot starts. A GND test can do one at a time and spot which one.

13. How are faults known about


TCA positions and AFS N1 target signal

1. What does EEC use to set thrust

ACUTE (Airbus Cockpit Universal Thrust Emulator) displayed using AFDX and CDS

2. What is the method of indicating thrust to crew

Manual = Throttle Resolver Angle (TRA). Automatic = N1 target set by AFS and TRA for thrust limitation and to display thrust mode

3. What are the thrust setting modes

When ALPHA FLOOR protection is commanded.

4. When is the thrust limitation over ridden


5. When is A/THR engaged but not active

Engaged Active, Engaged Inactive, Not Engaged. Decided by the PRIMS

6. What other engaged/active modes are there and what decides

A transition mode between Autothrust and Manual. EEC locks N1 speed to last Auto level to prevent sudden thrust changes to the Current TCA position

7. What is Memo Thrust Mode

Turbofan Power Ratio law is normal thrust computation using P20/T20, P30 and EGT. N1 is the backup to TPR.

8. What is TPR mode and N1 Mode

Rated N1 reversionary and Unrated N1 reversionary. Rated is simple tabled conversion from TPR to N1. Unrated sets idle throttle position to engine idle and max T/O to equal red line N1 and corrected for altitude

9. What are the revisionary modes

Yes so long as no more than 2 engines in N1 mode.

10. Can A/T be used in N1 mode

P0 and P20/T20 are compared to 3 independent ADIRU signals Ps Pt and TAT

11. What data us used by EEC for thrust logic and how is it checked

A sensor on the EEC to measure undercowl ambient

12. Where does P0 come from

3 ADIRUS and 4 EECs

13. How many available sources are there for the engine data

TPR = P30*(TGT/P20)*T20

14. What is the formula for TPR

By A/THR button or pushing throttle to TOGA or FLX whilst on GND. Also during ALPHA FLOOR protection.

15. How is A/T engaged

At the thrust reduction altitude the lever in CLimb. Also during ALPHA FLOOR protection when it orders TOGA thrust

16. When is A/T active

Primarily with Instinctive push buttons on throttles, Secondly with A/THR P/B, Auto when all throttles to idle, or 2 to reverse or when more than 1 engine not in A/T mode or a failure of more than 1 engine.

17. How is A/T disengaged


Hard wired to LP SOV solenoid in HMU, MPSOV (for 1 minute if OFF selected), Hard wired to EEC (each EEC CH also tells the other CH) for memory reset

1. What functions does the MASTER sw do


2. What does the Fire sw do

When MPSOV disagrees or any starting fault. The EIPM manages it via IOM

3. When does the ENG Master lever FAULT light come on and who manages it

EIPM 1A(eng2) & 1B(eng4) -> IOM 1+2 , EIPM 2A(eng3) & 2B(eng1) -> IOM 5+6 (12 14 12 and 23 21 56)

4. Which IOMs connects to which EIPM to which ENGs


ETRAC, TRPU, PDU, PLS (L and R), TLS, Flex shafts, Actuators and Manual drive units, 6 ballcsrew actuators operating through a flexible power train system

1. What are the components of the Thrust Reverser

Electrical Thrust Reverse Actuation Controller.

2. What does ETRAC stand for

3 separate commands. PRIM commands TLSPU to unlock TLS. EIPM to supply 115V to TRPU. EEC to command deploy to ETRAC. Called lines of defence

3. How many commands are required to operate it, What are they and what are they known as

Mechanically by locks in the upper actuators Called PLS and an electrical lock TLS

4. How is the Thrust Reverser locked

PRIM gives Flt/gnd to TLS

5. What is the 3rd line of defence

EIPM gives 115v to TRPU

6. What is the 2nd line of defence

EEC commands ETRAC

7. What is the 1st line of defence

A/C on GND, ENG running, THRUST REV selected.

8. What are the conditions for ETRAS to operate

A motor, disc brake and a resolver

9. What makes up the PDU

It needs to be energised to release. It holds the T/R closed and fully deployed

10. How and when does the PDU brake work

PDU is on top L side and 2 flex shafts connect to middle actuators, which then use 2 flex shafts each to power upper and lower actuators

11. Where is the PDU and how does it run the T/R

Upper has the locks, Middle drives the upper and lower, lower has the positions resolvers

12. What does each actuator do

2 primary lock prox sensors on upper actuators and the lower actuator position resolvers

13. How does EEC know the T/R position

It is Left T/R cowl middle. Does not control the Tertiary Lock

14. Where is ETRAC and which locking systems does ETRAC not control

L PLS directly and R PLS and PDU brake through the TRPU

15. How does the ETRAC command unlock

Left hand side 8 O’clock

16. Where is the TRPU

Tertiary lock in on L translating cowl at the bottom (L 6 Oclock Beam). Locked until energised. It mechanically locks and is electrically released. Has 2 prox sensors A + B

17. Where is the TLS and how does it function

2 TLS prox sensors

18. How does the EEC know the TLS is unlocked

Switches in the Throttle Control Assembly

19. How does ECC know TRA position

3rd Line of defence -> TRA < -4.5 / Rad ALT < 6ft / PRIM lets SSPC send 115V to TLS which is rectified by TLS PU. 2nd line of defence -> EIPM powers TRPU when TRA < -7 / on GND from LGERS / EIPM sends 28v to ETRAC. 1st Line of Defence -> EEC gets ON GND from LGERS, 1 ENG on and TRA = -9 deploy (-8 stow) EEC commands ETRAC to deploy. PDU brake releases and ETRAC powers PDU.

20. Describe T/R deploy

270VDC from the TRPU to release and sends feedback via a resolver

21. How is the PDU brake released and how does it signal its state

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

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

Oil System

Feed/cooling, Return, Vent/de-aeration/Breather

1. What are the primary areas of the oil system

RHS of fan case

2. Where is the oil tank

Centrifugal on rear face of gearbox

3. Where is the breather and what type is it

FOHE Right Hand fan cowl

4. How is oil cooling achieved and where is it located

Pressure filter. Scavenge filter on rear of oil tank (15micron). Line filters

5. How is oil filtered, how small and where are they

13 psid unless oil temp low when inhibited by EEC

6. When does the scavenge filter differential pressure switch operate


7. When does the scavenge filter bypass operate

Pressure pump and 9 scavenge pumps

8. What makes up the Pump assy

Front Bearing Housing, Internal GB front, IGB back, HP, IP, TBH , Centrifugal Breather, AGB, LBB

9. Where are the scavenge pumps

2(CHA +CHB) installed on FOHE. Measure differential px between oil pump o/p and IGB scavenge line.

10. Where are oil pressure transducers and how many and what do they measure

Ratiometric devices with constant V and variable R which is read by EEC

11. How do the oil pressure transducers work

25psid. On FOHE measuring same as the transducers. It feeds directly to AFDX and then to EEC

12. When does the oil pressure low trip and how is it measured and where

Oil px less than an N3 related value (Amber) and oil pressure less than minimum (red). Between amber and red a maint message is set. To set RED warning 2 I/Ps (of the 3 from the 1 px switch and 2 tranducers) are needed

13. What is the Low Pressure Indication logic