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Plunger type pumps can also be used to meter the fuel, but they cannot supply high fuel pressures.. Gear type pumps can supply higher fuel pressures than plunger type pumps.. Gear type p

ATA 71

1 Which of the following statements is correct about the 2 engine mounts shown here

a Both mounts can transfer forces in all 3 directions

b The forwad mount can only transfer forces in the z and x axes

c The aft mount can only transfer forces in the z and y axes

d The aft mount can only transfer forces in the z and x axes

2 What is the task of the drain collector assembly in this drain system?

a It connects all drain lines from the accessory drive to one common line routed to the drain mast

b It connects all drain lines of the drain system to one common line routed to the drain mast

c It collects fluid leaks from all drain lines

d It collects fluid leaks from the accessory drive seals

3 After landing you find this track on a drain mast What statement is correct?

a There was a leakage at the hydraulic pump drive seal The drive seal must be

replaced before the next flight

b There was a leakage at the hydraulic pump drive seal You must do a leak check

c There was a leakage at the hydraulic pump drive seal You must replace the

hydraulic pump

d This is normal, because hydraulic pumps always leak a little bit

4 How is the oil holding tank of this collector assembly emptied?

a It is automatically emptied by ram air during each flight

b You must open the drain valve to empty the holding tank

c Low pressure on the drain mast outlet during flight sucks the fluid out of the holding tank

d It is automatically emptied by engine bleed air before each flight

ATA 72

5 What are 4 typical major modules of a modern turbofan engine?

a The engine inlet, the compressor, the turbine and the engine exhaust

b The low pressure compressor, high pressure compressor, high compressor turbine and low pressure turbine

c The fan module, the core module, the turbine module and the accessory drive module

d The N1 rotor module, the N2 rotor module, the combustor module and the exhaust nozzle module

6 Where on the engine do you usually find titanium base alloy material?

a The low pressure compressor is usually made of titanium base alloy

b The fan cases and the engine gearboxes are usually made of titanium base alloy

c The high pressure turbine is usually made of titanium base alloy

d The N1 driveshaft is usually made of titanium base alloy

7 Some spinner cones have a soft tip What is the reason of this soft tip?

a The soft tip reduces the noise of the inlet airflow

b The soft tip reduces the injury danger if somebody is sucked into a running engine

c The soft tip is made of a special material that is extremely light to save weight

d The soft tip causes a small imbalance during operation to prevent ice built-up at the spinner cone

8 Which of the following statements about the attachment of fan blade is correct?

a Fan blades are always fitted loosely to the fan disc

b Fan blades must have a very tight fit because of their large weight

c Fan blades are attached in circumferential dovetail slots on the fan disc

d Fan blades are attached the fan stator case

9 Where on the fan module can you find adradable shrouds?

a On the outer fan stator case

b On the inner wall of the fan stator case in the area of the fan blades

c In the center hub of the fan frame

d On the inner wall of the fan stator case, in the area of the outlet guide vanes

10 What is the purpose of the mid-span shrouds on the fan blades?

a Mid-span shrouds serve as enforcements for the fan blades, to better withstand the centrifugal loads

b The shrouds help to keep the fan blade deflection within safe limits if very heavy loads act on them

c The shrouds help to split the inlet airflow into primary and secondary airflow

d The mid-span shrouds help to scare birds away

11 Which design method is used for this compressor rotor?

a This is a disc type compressor rotor

b This is a drum type compressor rotor

c This is a combined compressor rotor made of 1 drum and 3 discs

d This is a combined compressor rotor made of 2 drums and 2 discs

12 How many stages of this compressor rotor have axial dovetail slots to fit the rotor blades?

a Only the first stage has axial dovetail slots for the rotor blades

b The first 2 stages have axial dovetail slots for the rotor blades

c The first 3 stages have axial dovetail slots for the rotor blades

d All 9 stages have axial dovetail slots to fit the rotor blades

13 What is the name of this rotor blade attachment?

a Dove tail attachment

b Fir tree attachment

c Lemon tree attachment

d Fir tail attachment

14 What is the advantage of tangential struts compared with radial struts used in the turbine frame?

a Tangential struts minimize the stress on the frame hub caused by thermal

expansion

b Tangential struts are lighter than radial struts

c Tangential struts are cheaper to manufacture than radial struts

d Tangential struts look better than radial struts

15 What is the advantage of core mounted gearboxes compared with fan case mounted gearboxes?

a Core mounted gearboxes are more compact and therefore lighter than fan case mounted gearboxes

b Core mounted gearboxes are easier to access than fan case mounted gearboxes

c Engines with core mounted gearboxes have a smaller frontal area than fan case mounted gearboxes

16 Which kind of loads can be transmitted by a floating bearing?

a Weight loads, shock loads, thermal loads and thrust loads

b Weight loads and centrifugal loads

c Weight loads, centrifugal loads and thrust loads

d Weight loads only

17 What is pressure balancing?

a Pressure balancing is a method of reducing axial loads on fixed bearings in an

engine

b Pressure balancing is a method to reduce axial loads on floating bearings in an engine

c Pressure balancing is a method to reduce radial loads on fixed bearings in an engine

d Pressure balancing is a method to reduce the oil pressure at the lubrication nozzle

18 Which lubrication method is shown in this graphic?

a The direct lubrication method

b The indirect lubrication method

c A combination of a direct and an under-race lubrication method

d The outer-race lubrication method

19 What must you do if one fan blade is damaged and has to be replaced?

a This is not allowed as you cannot replace just one blade You must always replace the whole set

b First remove all the fan blades and calculate a new distribution with the new blade

c You must replace the damaged blade with a new blade which has the exactly same moent weight

d You must adjust the change in the moment weight by adding balance weights

20 Assume that during blending 20 gram of blade material has been removed What has to

be done to the blade so that it can be put on the fan rotor again?

a You must add a balance weight of 20 gram on the spinner

b You must blend 20 gram of material at the tip of the opposite blade

c You must measure the new moment weight, calculate the required balance weight and add it to the spinner

d You must always perform a complete computerized rebalancing of the fan rotor

21 In this example which components of the high pressure compressor can be inspected by

a rigid borescope?

a All the stator vances of all compressor stages

b All the rotor blades of all compressor stages

c Some rotor blades of all stages and all stator vanes of all stages

d You can only inspect the rotor blades of stage 1 to 4, stage 6 and 7 and of stage 9 and 10

22 How do you rotate the N2 rotor system for a borescope inspection?

a Use the shaft of the borescope and push on the rotor blades

b Rotate the N1 rotor fast enough so that the N2 rotor will follow

c Motorize the engine with the pneumatic starter motor at a very low speed

d By a cranking device connected to the accessory gearbox or transfer gearbox

ATA 73

23 Where can you find a flow divider valve in an engine fuel system?

a On engines with duplex fuel nozzles inside each nozzle

b Only on engines with 2 fuel manifolds

c On all engines with airspray nozzles

d Only on modern turbofan engines

24 What is the name and the task of the highlighted fuel line in the engine fuel system?

a It is the fuel bypass return line It returns the fuel that is not needed for combustion

to the tank

b It is the fuel bypass return line It returns the fuel that is not needed for combustion

to the fuel pump

c It is the fuel bypass return line It returns the fuel to the oil cooler if it is too cold for combustion

d It is the fuel recirculation line It recirculates the fuel back to the tank if it is too hot for combustion

25 What is the main difference between plunger type fuel pumps and gear type fuel

pumps?

a Plunger type pumps can also be used to meter the fuel, but they cannot supply high fuel pressures

b Gear type pumps can supply higher fuel pressures than plunger type pumps

c Gear type pumps can also be used to meter the fuel, but plunger type pumps can supply higher fuel pressures

d Plunger type pumps can also be used to meter the fuel and they can supply higher fuel pressures

26 What is a wash screen in the fuel system?

a It is a filter element, that can be washed out during engine maintenance

b It is a very fine filter screen for the servo fuel flow that is continuously cleaned by the main fuel flow

c It is a screen which washes away the particles that are caught in the main filter element

d It is a screen that can be used to wash high pressure filter elements

27 Which type of fuel nozzle is always a single flow nozzle?

a Airspray nozzles are always single flow nozzles

b Fuel spray nozzles are always single flow nozzles

c The duplex nozzle is a single flow nozzle

28 Where do you find shrouds in the fuel system of modern engines?

a All fuel lines of the engine fuel system are shrouded lines

b The fuel supply line between the tank and the low pressure fuel pump is usually a shrouded line

c Only the fuel line couplings of the high pressure fuel system are usually shrouded

29 Which signals does the fuel control unit need for constant speed control?

a N1 and N2 signals from engine

b N2 signal from the engine and N2 command signal from the cockpit

c N2, CIT and CDP signal from the engine

d N1 signal from the engine, N2 command signal from the cockpit and aircraft

configuration signals

30 What is the difference between minimum idle and approach idle?

a Approach idle speed is higher than minimum idle speed

b Minimum idle speed is higher than approach idle speed

c For approach idle the thrust lever must be pushed a little bit out of the idle position

d For approach idle the CIT signal is needed but not for minimum idle

31 What happens to the N1 during the climb flight phase on a constant thrust controlled engine?

a Nothing, the N1 remains constant until a new power setting is selected

b The N1 decreases because the density decreases

c The N1 increases because the density decreases

d The N1 increases because the density increases

32 Which of the following parameters is usually kept constant for fuel metering?

a The flow area of the fuel metering valve

b The pump supply pressure

c The differential pressure across the fuel metering valve

d The differential pressure across the bypass valve

33 Which hydromechanical component converts a speed controlled fuel control unit into a thrust controlled fuel control unit?

a The density compensation

b The power management computer

c The torque moter at the fuel control unit

34 Which input signals are needed by the limiting section of the fuel control unit?

a CIT, CDP and N2

b CIT, CDP and N1

c CDP and CIT

d CIT, CDP, N1 and thrust lever angle (TLA)

35 What happens to the engine in this condition?

a The engine continues to accelerate

b The engine keeps the selected speed

c The engine decelerates

d The engine shuts down

36 What is the difference between an ECU and an EIU?

a There is no difference in function ECU and EIU are just different names for the same component

b The EIU controls the engine and the ECU performs the fuel metering

c There are 2 EIUs on an aircraft but only 1 ECU because the ECU has 2 channels

d The ECU controls the engine and the EIU is used on some aircraft as an interface between aircraft and engine

37 What is the purpose of the flyweight governor in this HMU?

a The governor is used to control the fuel metering valve

b The governor is used as an overspeed protection

c The governor is used to control the N2 speed of the engine

d The governor is necessary for engine starting until the PMA supplies sufficient power for the ECU

38 Which adjustments are necessary after replacement of a fuel metering unit (FMU) on a FADEC controlled engine?

a Idle adjustment and part power adjustment

b Idle adjustment only

c Gravity adjustment only

d No adjustments are necessary

39 When does the ECU use the power supply from the aircraft?

a Always during normal engine operation because this is the normal power supply for the ECU

b The ECU uses the power supply from the aircraft when the PMA fails and at the beginning of the engine start

c The ECU uses the power supply from the aircraft only in flight if the PMA fails

d The ECU uses the power supply from the aircraft only if it is ised for maintenance tests on ground

40 Most engine sensors have 2 signal lines, 1 for each channel in the ECU Why is there only

1 signal line from the pressure sensor Po, Ps12 and Ps3?

a Because the pressure signals are less important for engine control

b Because the ECU of 1 engine can use the respective pressure signals of the other engines on the aircraft

c Because the 2 channels receive the pressure signals from pressure transducers in the ECU

d Because the ECU calculates the Ps12 and Ps3 based on the Po and the engine speed N2

41 What is the purpose of the thrust rating plug in the FADEC system?

a From the thrust rating plug the ECU gets the maximum permissible rotor speed of the engine

b The rating plug limits the throttle movement in the forward direction

c From the rating plug the ECU gets the maximum permissible operating hours from the engine

d From the rating plug the ECU gets the maximum T/O thrust information for the engine

ATA 74

42 Which of the following statements about an ignition system is correct?

a The ignition system must be switched on all the time to keep the engine running

b The ignition system is only switched on during engine start

c The ignition system must always be switched on manually

d The ignition system is used for engine start and for continuous ignition

43 Which of the following statements about an ignition exciter is correct?

a The ignition exciter mainly has a transformer that generates an outout voltage of about 2000 V AC

b The ignition exciter has capacitors that can store a very high electrical energy for a long time

c The output voltage is always 0 volts when you switch off the input voltage

44 Which statement is correct about the highlighted area of the plug connector?

a This is an electrical contact that is always connected to ground

b This is part of the connector insulation

c This contact gives the electrical energy to the plug You can touch it when the

system is switched off

d This contact gives the electrical energy to the plug You must never touch it even when the system is off

45 What statement is correct about the 2 igniter plugs you can find on each engine?

a Each plug has its own ignition exciter and 1 or 2 plugs work at a time dependent on the mode of operation

b Both plugs are supplied from the same ignition exciter and always work at the same time

c Each plug has its own ignition exciter, but both plugs always work at the same time

d Both plugs are supplied from 1 ignition exciter The second box becomes active when the first box fails

46 Which component of the start system is activated by the engine master switch during engine start?

a The pneumatic starter motor

b The clutch in the pneumatic starter motor

c The N2 rotor shaft

d The starter shut-off valve

47 Where do you usually find the starter valve on a turbofan engine?

a Always in the 6 o’clock position at the transfer gearbox

b In the lower area of the engine so that it is easily accessible on ground

c In the engine pylon at the beginning of the starter duct

48 What is the meaning of the term “Starter cool down time”?

a This term describes the time that a starter can operate continuously before it must

be stopped to cool it down

b This term describes the time that a starter must cool down after operation before it can be used again

c This term describes the number of subsequent start sequences that a starter is permitted to do

d This term describes the time that it takes to cool the starter down to ambient

temperature after operation

ATA 75

49 What is the purpose of the variable bleed valves system?

a It controls cooling air from the LP compressor into the core compartment

b It protects the LP compressor against stall and surge

c It protects the HP compressor against stall and surge

d It controls cooling air from the LP compressor into the fan compartment

50 What is the difference between a turbine clearance control system and a compressor clearance control system?

a Turbine clearance control is either active or passive, but compressor clearance control is always passive

b Turbine clearance control uses HPC bleed air, but compressor clearance control uses fan air

c Turbine clearance control uses air for cooling, but compressor clearance control uses air for heating

d Turbine clearance control is always passive, but compressor clearance control is active or passive

51 Which air is usually used for cooling of the engine core compartment?

a Ram air

b Fan air

c LPC bleed air

d HPC bleed air

52 How are the VSVs usually actuated?

a By individual torque motors on each variable stator vane

b By 2 hydraulic actuators VSVs on the left by the LH actuator and VSVs on the right

by the RH actuator

c By 1 or 2 hydraulic actuators that are supplied by engine driven hydraulic pumps

d By 1 or 2 hydraulic actuators driven by high pressure fuel from the engine fuel

system

53 Which statement is correct about this engine without a FADEC system? When the

engine is not running…

a … the VSVs are open and the VBVs are closed

b … the VSVs are closed and the VBVs are open

c … the VSVs and the VBVs are closed

d … the VSVs and the VBVs are open

54 Which signals are necessary for this main engine control to control the VSVs and VBS?

a The N2, the CIT and the VSV and VBV feedback signals

b The N2, the CIT, the CDP and the VSV and VBV feedback signals

c The CIT, the CDP and the VSV and VBV feedback signals

d The N2 and the VSV and VBV feedback signals

55 How are the HP compressor bleed valves usually actuated?

a By fuel pressure from the HMU

b By hydraulic pressure from the engine drive hydraulic pumps

c By internal springs

d By air pressure from the aft stages of the HPC

56 The CIT sensor is also called T25 sensor Where is this CIT sensor usually located on an engine?

a The CIT sensor is usually installed in the engine intake in front of the fan

b The CIT sensor is usually installed in the fan frame in front of the HP compressor

c The CIT sensor is usually installed in the fan exhaust duct behind the variable bleed valves

d The CIT sensor is usually installed in the fan frame in front of the LP compressor

57 Which of these turbines has an active clearance control system?

a The HP turbine only

b The LP turbine only

c The HP turbine and the LP turbine

58 Which signals are minimum to activate an active clearance control system during cruise?

a The flight altitude and the turbine case temperature

b The rotor speeds N1 and N2

c The flight altitude and the rotor speed N2

d The turbine case temperature, the turbine case diameter and the rotor size

59 How are clearance control valves usually operated?

a By air pressure from the HP turbine

b By fuel pressure from the HMU

c By electric actuators and gear drives

d By air pressure from the LP compressor

60 Which air is usually used as sealing air for the bearing compartments?

a Fan air

b LPC discharge air

c HPC discharge air

d HPC intermediate pressure

61 When can the engine get to a bowed rotor condition?

a During operation when the cooling airflow for the core compartment is not

sufficient

b During operation when the cooling airflow for the core and for the fan compartment

is not sufficient

c After engine shut-down when the cooling airflow for the core and for the fan

compartment is not sufficient

d After engine shut-down when the lower half of the engine becomes colder than the upper half

ATA76

62 Which component on this engine start system is mechanically controlled?

a The LP fuel valve

b The HP fuel shut-off valve

c The igniter plugs

d The metering valve in the fuel control unit

63 What is controlled by the highlighted engine control lever?

a The rotational speed of the engine

b The rotational reverse speed of the engine

c The activation of the thrust reverser and the rotational speed of the engine

d The activation of the thrust reverser

64 The engine is not running What happens to the servovable if you pull the highlighted circuit breaker of the engine start system?

a Nothing

b The solenoid of the servovable is de-energized and the pressurizing valve opens

c The solenoid of the servovable is energized and the pressurizing valve opens

d The solenoid of the servovable is de-energized but the pressurizing valve remains closed

65 What kind if transmission system is used on this fuel control unit?

a A mechanical rack and pinion transmission

b A mechanical crank lever transmission

c An electrical motor driven worm gear transmission

66 What is the purpose of a friction brake in the engine control system?

a It prevents very rapid throttle movements

b It stops the movement of the control system when the autothrottle servo motor is active

c It removes the internal friction in the mechanical transmission system

d It makes sure that the throttle remains in the selected position when the pilot takes his hand off