AGK AIRFRAME AND SYSTEMS >>>Sample Question

AIRFRAME AND SYSTEMS

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1. The fuel system boost pumps are used to:

A) avoid the bubbles accumulation and feed the lines with fuel for directing it to the engine at a positive pressure.

B) feed the fuel control units, which inject the pressurized fuel into the engine

C) avoid the bubbles accumulation

D) feed the lines with fuel for directing it to the engine at a positive pressure

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2. Why is the capacitance-type fuel quantity gauge system the system that is most often used on large turbine aircraft?

A) Because it is a lot simpler and it's weight are less than other systems

B) Because it measures the mass of fuel rather than the volume of fuel in the tank

C) Because it measures the volume of fuel more accurately.

D) Because it is more cost efficient in the way it is constructed and installed.

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3. An electrically activated and operated fuel valve is called a(n):

A) Electronically valve

B) Motor valve.

C) Emergency valve

D) Solenoid valve

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4. During fuelling operations

A) all external lights should be off

B) only external yellow hazard lights should be on

C) all external lights should be on.

D) Nav lights should be off and strobe lights on.

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5. The maximum quantity of fuel that can be dumped with the jettisoning system is:

A) All fuel until the maximum landing weight is reached.

B) All fuel

C) All up to a defined reserve quantity

D) 15 tons.

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6. Fuel booster pumps are necessary in large aircraft:

A) to maintain fuel supply to the LP pumps at all times

B) to maintain supply to the HP pumps at low altitude

C) to prevent cavitation of the engine driven pump.

D) to maintain fuel supply to the engines during critical flight phases

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7. In a compensated capacitance type quantity indicating system, the contents gauge of a half-full fuel tank indicates a fuel mass of 8000 lb. If a temperature rise increased the volume of fuel by 5 %, the indicated fuel weight would:

A) increase by 10 %.

B) decrease by 5 %.

C) increase by 5 %.

D) remain the same

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8. A fuel system booster pump other than pumping fuel to the engine may also be used for:

A) jettisoning and heating of the fuel

B) transfer and heating of the fuel

C) jettisoning the fuel and as an emergency pump in the event of main pump failure

D) transfer and jettison of the fuel

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9. How much fuel is required for a retained sample?

A) 2.5 litres

B) 5 litres.

C) 1.5 litres.

D) 2 litres

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10. To indicate that a refuelling bowser carries JET Al aviation kerosene:

A) yellow and black stripes are marked on the refuelling hose

B) JET Al would be painted in 30cm high symbols on the side of the container

C) the driver wears a straw yellow water and fuel proof jacket

D) JET Al is printed in white on a black background label positioned prominently on the vehicle

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11. An aircraft using MOGAS:

A) is more likely to be affected by vapour locking and carburettor icing

B) will suffer from a loss of power during take-off

C) is likely to be affected by detonation at cruise power

D) must have booster pumps fitted in the fuel tanks

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12. The CROSS-FEED fuel system enables:

A) only the transfer of fuel from the centre tank to the wing tanks

B) the supply of the jet engines mounted on a wing from any fuel tank within that wing

C) the supply of any jet engine from any fuel tank

D) the supply of the outboard jet engine from any outboard fuel tank

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13. The refuelling in a transport jet aircraft is made...

A) Through a unique point (an underwing refuelling centre).

B) Through the refuelling cap of every tank.

C) By means of the aircraft suction pumps through a unique point (an underwing refuelling centre).

D) By means of the aircraft suction pumps

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14. On a jet aircraft, when installed, fuel heaters are:

A) installed in each tank

B) not necessary at all

C) located on the engines

D) installed only in the centre tank

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15. The fuel tanks in small aircraft are mainly located:

A) In the tail section of the aircraft

B) Close to the engine.

C) In the wings

D) In the fuselage

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16. The advantage of a capacitor type fuel contents gauging system is that the circuit:

A) responds to changes in specific gravity

B) compensates for high altitude flight

C) compensates for aircraft attitude changes

D) responds automatically to extremely low temperatures

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17. The purpose of baffle check valves fitted in aircraft fuel tanks is to:

A) damp out movement of the fuel in the tank

B) prevent positive pressure build up inside the tank

C) close the vent lines in case of turbulence

D) prevent fuel movement to the wing tip

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18. The cross-feed fuel system is used to:

A) feed every engine from any fuel tank

B) allow the unusable fuel elimination

C) automatically fill every tank up to the desired level

D) allow the fuel to be quickly thrown away in case of emergency

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19. Special fuel consumption schedules during flight are designed due:

A) to ensure fastest rate of fuel dumping in case of emergency where time is critical

B) to minimise the wing G-loads and preserve main tank fuel for landing

C) to keep fuel from freezing during high level cruise for a longer period of time

D) to keep wing fuel as low as possible in event of a crash-landing

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20. Fuel jettisoning is:

A) transferring fuel to the trim tank

B) venting fuel to the atmosphere

C) dumping fuel in an emergency

D) producing a jet spray for combustion

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21. Prior to fuelling an aircraft, which of the following precautions must be carried out?

A) The fuelling hose must be earthed to the nose undercarriage before tank caps are removed

B) The fuelling hose must be bonded to the aircraft structure prior to removal of fuel tank caps

C) The fuelling hose must be earthed to ground at all times.

D) The fuelling hose must be bonded to the aircraft immediately after fuel tank caps are removed

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22. JET A1:

A) is used as a rocket propellant.

B) is normally used in piston engine aircraft

C) conforms to British Standard BS4040.

D) has a lower freezing point than JET A fuel

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23. When refuelling a swept-wing aircraft, the order of filling the fuel tanks should be

A) outer tanks, inner tanks, centre tanks

B) centre tanks, inner tanks, outer tanks.

C) centre tanks, outer tanks, inner tanks.

D) based on pilot's judgement

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24. On a transport type aircraft the fuel tank system is vented through:

A) Ram air scoops on the underside of the wing.

B) A pressure regulator in the wing tip.

C) The return lines of the fuel pumps

D) Bleed air from the engines

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25. A failed capacitance fuel contents gauge would:

A) remain fixed on the last contents noted before failure.

B) show full deflection high

C) fluctuate between high and low readings

D) show full scale deflection low

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26. The purpose of the barometric correction in a fuel controller is to:

A) increase the fuel-to-air ratio when altitude increases

B) maintain a constant fuel metering whatever the altitude

C) maintain the correct weight fuel to air ratio when the altitude increases

D) reduce the fuel-to-air ratio when altitude increases

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27. On A/C with a fuel pressure gauge, where is the pressure normally measured? (Aircraft with fuel injection)

A) At the selector valve outlet

B) At the injection nozzles

C) At the tank outlet

D) At the inlet of the fuel injection metering unit

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28. During refuelling operations:

A) Radio transmissions are not forbidden

B) The aircraft should be bonded to the refueller before refuelling pipes are coupled

C) A refuelling zone is to be established to at least 100 m

D) Passengers are forbidden to remain on the aircraft regardless of the type of fuel being replenished

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29. If a fuel tank with a capacitive quantity system was filled with water instead of fuel, the gauge would indicate:

A) full scale high (max).

B) full scale low (zero).

C) it would indicate the same as if it were filled with fuel

D) it would freeze at the last known indication

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30. Adjustments may have to made to an aircraft's engine fuel system if it has been refuelled with JET B instead of its normal JET Al fuel, these adjustments are to cater for:

A) the change in the viscosity of the fuel

B) the change in the specific gravity of the fuel

C) the lack of HITEC lubricant in the fuel

D) the change in the calorific value of the fuel

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31. A one way check valve will:

A) start flow when input pressure is less than output pressure

B) stop flow when input pressure is greater than output pressure

C) stop flow when the thermal relief valve opens.

D) stop flow when input pressure is less than output pressure.

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32. What will be the effect on the indicated fuel contents if a capacitive system fuel contents gauge fails in flight?

A) the gauge will remain in the high position

B) the gauge will fluctuate between high and low contents.

C) the gauge will indicate full scale deflection low

D) the gauge will remain in the last fixed position.

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33. On most transport aircraft, the low pressure pumps of the fuel system are:

A) centrifugal pumps

B) diaphragm pumps

C) piston pumps.

D) gear type pumps.

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34. AVTUR Jet A1:

A) is always light straw in colour

B) is coloured blue.

C) is red in colour

D) is coloured clear to light straw (pale yellow).

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35. Unusable fuel is:

A) fuel in the inboard wing tanks which is used for centre of gravity control

B) fuel in the outboard wing tanks to compensate for excessive wing flexure in flight

C) remaining fuel in the tanks and fuel lines which cannot be used for combustion

D) fuel required for diversion and holding

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36. What are the advantages of a Flexible Fuel Tank over an Integral Tank?

A) Flexible tanks do not suffer from the corrosion problems of an integral tank

B) Leaks are easier to locate

C) There is a greater tank capacity

D) There is a weight saving as the tanks are made from a flexible plastic

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37. When baffles are fitted to aircraft fuel tanks, the purpose is to:

A) reduce fire risk when fuelling

B) separate air from the fuel during fuelling operations

C) prevent surge of fuel within the tank during flight

D) control the fuel flow to the main feed

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38. The fuel system boost pumps are submerged in the fuel :

A) to shorten the fuel lines, so minimising the pressure losses

B) to cool the pumps

C) to prime the pumps

D) because their efficiency is greater

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39. In the event an APU is required to be running during fuelling operations, which of the following precautions must be observed?

A) the APU must be started after fuel tank caps are removed

B) the APU must be shut down (switched off) while fuel is being transferred to the aircraft

C) the APU must be started before fuel tank caps are removed

D) the APU can only be run if it is fitted with an exhaust extension, 6m in length

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40. Fuel is pressurized to:

A) keep constant fuel flow in negative G

B) prevent vapour lock

C) prevent cavitation

D) prevent fuel icing

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41. The indications of a failure of the capacitive fuel indication system will be:

A) a full deflection of the gauge to empty

B) a deflection of the gauge to full

C) no change in contents indication

D) a yellow flag on the gauge

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42. An integral type fuel tank is:

A) a fuel tight cavity incorporated in a box spar wing construction

B) a special tank fitted in the fuselage

C) A permanent external gravity tank

D) a bag which is in the wings of the aircraft

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43. Waxing is:

A) the depositing of water from the fuel at low temperatures

B) the depositing of water from the fuel at high temperatures

C) the depositing of heavy hydrocarbons from the fuel at low temperatures

D) the depositing of heavy hydrocarbons from the fuel at high tempe

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44. How much fuel can be jettisoned?

A) All.

B) A specified amount must remain

C) A specific amount

D) The captain decides

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45. The fuel required for a planned flight is 28,000kg. The fuel in the tanks is 24,000 litres (SG of the fuel is 0,8). The required fuel volume is:

A) 8,800 imperial gallons

B) 2,420 imperial gallons

C) 880 imperial gallons

D) 24,200 imperial gallons

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46. While refuelling with passengers on board, when a loading bridge is in use:

A) ground servicing must not be carried out

B) the rear left or right door must be manned constantly by a cabin attendant ready for use as an emergency exit using the inflatable escape slide

C) catering and cleaning must not be carried out.

D) two sets of extra steps must be provided, one of which must be at the rear of the aircraft.

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47. The pressurization of tanks is maintained by the fuel

A) dump system

B) tank drains

C) vent system

D) top off unit

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48. The pressure usually produced by the Boost Pumps (BP) of the fuel supply system is within the following range:

A) 5 to 10 psi

B) 3000 to 5000 psi

C) 20 to 50 psi

D) 300 to 500 psi

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49. What is the ratio between the litre and the US gallon?

A) 1 litre = 3.78 USG

B) 1 litre = 4.55 USG.

C) 1 litre = 4.55 USG.

D) 1 USG = 3.78 litres

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50. If the specific gravity of a fuel is known to be 0.7 the weight of 20 imperial gallons of that fuel would be:

A) 140 lb

B) 210 lb

C) 14 lb

D) 20 kg

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51. From the statements below, which aircraft should have a fuel dumping system?

A) Aircraft which have a Maximum Zero Fuel Weight which exceeds the Maximum Take Off weight

B) Aircraft that have a maximum landing weight limitation below the maximum take off weigh

C) Aircraft with a maximum landing weight which will exceed the maximum brake efficiency speed

D) Aircraft that have a maximum landing weight limitation above the maximum take off weight

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52. Baffles are fitted in aircraft fuel tanks:

A) to channel fuel to the vent valve.

B) to prevent the static build up in the tank during refuelling

C) to prevent fuel surging during aircraft manoeuvres

D) to assist in correct fuel distribution

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53. Fuel is heated:

A) to maintain a constant viscosity

B) to prevent water contamination.

C) to stop cavitation in the High Pressure Fuel Pump

D) to stop ice blocking the Low Pressure fuel filter

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54. On an aircraft equipped with a compensated capacitance type fuel quantity indication system graduated to read in kg, the temperature increases just after the tanks are half filled with fuel. If the fuel expands by 10%, the gauges will show:

A) a decrease of 10% of the volume factored by the new specific gravity

B) an increase of 10%.

C) the same amount

D) a decrease

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55. During fuelling the automatic fuelling shut off valves will switch off the fuel supply system when:

A) the fuel has reached a predetermined volume or mass

B) the surge vent tank is filled

C) there is fire

D) fuelling system has reached a certain pressure

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56. The Maximum Zero Fuel Weight:
1. Is a limitation set by regulation.
2. Is designed for a maximum load factor.
3. Is due to the maximum bending moment at wing root.
4. Requires to empty external tanks first.
5. Requires to empty internal tanks first.
The correct combination of true statements is:

A) 1,3,5.

B) 2,4.

C) 1,2,3.

D) 2,5.

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57. The fuel supply system on a jet engine includes a fuel heating device, upstream of the main fuel filter so as to:

A) ease low pressure pumps work by increasing fuel fluidity

B) maintain and improve fuel heating power

C) prevent fuel from freezing in fuel pipes due to low temperatures at high altitude

D) prevent, at low fuel temperature, the risk of ice formation from water contained in the fuel

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58. The automatic fuelling shut off valve:

A) stops fuelling as soon as a certain pressure is reached

B) cuts off the fuel in case of engine fire

C) stops fuelling as soon as the fuel spills into the ventline

D) stops fuelling as soon as a certain fuel level is reached inside the tank

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59. Why are baffles fitted to aircraft fuel tanks?

A) to direct fuel to the main supply.

B) to assist in cooling the fuel tank.

C) to assist in heating the fuel tank.

D) to equalize fuel pressure within the tank, so preventing surge

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60. The capacitance type fuel gauging system indicates the fuel quantity by measuring the:

A) electrical resistance change

B) resistivity variation of the fuel

C) density variation of the fuel

D) dielectric change between fuel and air

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61. Adjustment may have to be made to an aircraft fuel system if it has been refuelled with JET B instead of its normal JET A1 fuel. These adjustments are to cater for:

A) the change in flash point of the fuel

B) the change in specified gravity of the fuel

C) the change in combustion efficiency of the fuel

D) the change in freeze point of the fuel

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62. Fuel pumps submerged in the fuel tanks of a multi-engine aircraft are:

A) centrifugal low pressure type pumps

B) low pressure variable swash plate pumps

C) centrifugal high pressure type pumps

D) high pressure variable swash plate pumps

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63. When checking the fuel for possible water content, the presence of water will be indicated by

A) The water will be on top of the fuel in the fuel strainer because it is lighter than the fuel

B) The water will be found at the bottom of the strainer, because it is heavier than the fuel

C) Change in the colour of the fuel

D) Impossible to tell because they will mix

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64. The aircraft cannot be refuelled while:

A) a ground power unit is operating on the ramp

B) passengers are walking through the refuelling zones

C) passengers are boarding.

D) the APU is running

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65. AVTUR or JET A1:

A) is a 97 octane fuel which prevents detonation in gas turbine engines

B) varies in colour between clear and straw yellow

C) is a wide cut fuel which is not normally used in civilian transport aircraft.

D) is a gasoline type fuel with a high flash point

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66. An integral fuel tank:

A) is mounted externally beneath the wing or at the wingtips.

B) is part of the aircraft wing structure

C) is an essential component of an integrated fuel measurement system

D) is made from re-enforced rubber sheeting and attached to the aircraft structure

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67. The fuel cross feed valves are fitted in order to facilitate:

A) refuelling when only one bowser is in use.

B) isolation of the engine from the fuel system in the case of an engine fire

C) the use of fuel from any tank to any engine

D) transfer of fuel between the main fuel tanks

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68. Capacitive fuel quantity measurement systems compensate for fuel movement in the tanks by:

A) measuring fuel volume, rather than depth

B) measuring the specific gravity of the fuel

C) using more than one measuring probe per tank.

D) measuring fuel mass, rather than volume

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69. Cloudiness of a sample of AVTUR is an indication of:

A) iron-oxide particles in suspension

B) fungus growth.

C) water in suspension

D) waxing.

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70. Refuelling with passengers on board is not permissible:

A) Refuelling with passengers on board is not permissible: A) if the aircraft has more than twenty seats and the ratio of cabin attendants to passengers is greater than 1:50 and it is a wide bodied jet.

B) in any of the above cases.

C) on a fixed wing aircraft

D) if AVGAS is being used

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71. To what distance should a fuelling zone extend from a fuelling point or vent point?

A) 16 m

B) 6 m

C) 50 m

D) 15 m

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72. Fuel tanks are vented so that:

A) excess fuel can drain away rapidly after over filling

B) a large positive pressure is maintai

C) a vacuum will not form as fuel is used

D) fuel can be jettisoned in an emergency

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73. The Low Pressure engine driven pump:

A) backs up in case of a double booster pump failure

B) assists in the refuelling operation if only low pressure refuelling systems are available.

C) backs up in case the engine High Pressure Pump fails

D) pressurises the fuel tanks to assist flow to the booster pumps

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74. Fire precautions to be observed before refuelling are:

A) Ground Power Units (GPU) are not to be operated.

B) All bonding and connections to the earth terminal between ground equipment and the aircraft should be made before filler caps are removed

C) Aircraft must be more than 10 metres from radar or HF radio equipment under test

D) Passengers may be boarded (traversing the refuelling zone) providing suitable fire extinguishers are readily available.

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75. Fuel tank booster pumps are:

A) gear type, high pressure

B) gear type, low pressure

C) centrifugal, low pressure.

D) centrifugal, high pressure

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76. The colour of AVGAS 100 is:

A) green

B) light straw

C) blue

D) red.

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77. Booster pumps as fitted in a fuel system are:

A) Electrically driven

B) Used solely to provide an emergency pressure in the event of an engine driven pump failure

C) Engine driven

D) Only fitted to piston engine fin systems

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78. Un-dissolved water in a fuel sample:

A) will appear as droplets on the side of the container, or as bulk water on the bottom

B) will cause the fuel to appear cloudy

C) will change the colour of AVTUR

D) will appear as free floating droplets in the fuel

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79. The disadvantage of refuelling the aircraft to " tanks full" the night before a departure in the heat of the day is that:

A) the change in calorific value may reduce engine power to below sufficient.

B) the R.P.M. governor will be rendered inoperative.

C) the change in the specific gravity may cause the aircraft to be overweight

D) the change in the volume of the fuel may cause it to spill through the vent system

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80. Fuel dump systems are required:

A) on all transport category aircraft with more than 150 seats.

B) on all transport category aircraft

C) on all transport category aircraft where the Maximum Take-Off Weight (MTWO) is significant higher than the Maximum Landing Weight (MLW).

D) on aircraft with a Maximum Take-Off Weight (MTOW) higher than 5.7 tons.

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81. During fuel jettison, the aircraft is protected against running out of fuel by:

A) the crew remaining alert

B) preset jettison quantity switches

C) low level float switches

D) high level float switches.

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82. When fuelling an aircraft, what action may be taken to reduce the build up of static electricity?

A) To keep the fuelling hose as short as possible

B) To use a long fuelling hose

C) To reduce the flow rate of the fuel

D) To increase the flow rate of the fuel

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83. The purpose of the baffles in an aircraft's integral fuel tank is to:

A) Prevent overpressure in the tank

B) Prevent mixture of the fuel and hydraulic fluid

C) Prevent the fuel from flowing to the wing tips during abnormal manoeuvre (side slipping...).

D) Prevent the fuel from flowing in the vent lines

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84. In a typical fuel/oil heat exchanger:

A) heat is transferred from the hydraulic fluid to the water system

B) heat is transferred from fuel to ram air.

C) fuel and hydraulic fluid are mixed for efficient heat transfer

D) heat is transferred from the hydraulic fluid to the fuel

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85. If a fuel sample appears cloudy or hazy, the most probable cause is:

A) anti-microbiological additives.

B) water contamination

C) mixing different fuel grades

D) oil in the fuel

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86. The LP fuel pump is driven by:

A) Air pres

B) The engine

C) The electrical system

D) Hydraulic pressure

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87. In an aircraft low pressure refuelling system, what is fitted to prevent a fuel tank from becoming over pressurised?

A) low level float switches

B) vent valves.

C) high level float switches

D) fuel hose pressure relief valves

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88. In an aircraft low pressure refuelling system, what is fitted to prevent a fuel tank from becoming over pressurised?

A) fuel hose pressure relief valves

B) low level float switches

C) high level float switches

D) vent valves

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89. Refuelling a fixed wing aircraft with passengers embarking is permissible:

A) only if the seating capacity is more than 20, there are at least two exits, and other safety precautions

B) only if there is a member of the cabin staff manning the exit door

C) only if the seating capacity is less than 20.

D) under no circumstances whatsoever

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90. AVGAS 100LL is:

A) coloured green and has a higher octane rating than 100L

B) coloured green and has the same resistance to detonation as 100L

C) coloured green and contains less lead than 100L.

D) coloured blue and has the same octane rating as 100L

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91. Fuel stored in aircraft tanks will accumulate moisture. The most practical way to minimize this when a plane is used every day or so is to:

A) keep tank vents plugged and filler cap tight

B) use only high octane gasoline

C) drain tanks at end of each day's flight

D) keep tanks topped off when plane is not in use

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92. The vapour lock is:

A) The abnormal mixture enrichment caused by a greater gasoline vaporisation in the carburettor.

B) A stoppage in a fuel feeding line caused by a fuel vapour bubble.

C) The exhaust gases obstructions caused by an engine overhe

D) The effect of the water vapour bubbles in the induction manifold caused by the condensation

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93. The function of a feed box in the fuel tank is to:

A) increase the fuel level at the boost pump location

B) trap fuel sediments or sludge in the lower part of the tank

C) distribute the fuel to the various tanks during refuelling

D) ventilate the tank during refuelling under high pressure

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94. The purpose of the fuel cooled oil cooler is to:

A) cool the oil

B) heat the oil and cool the fuel

C) heat the fuel

D) heat the fuel and cool the oil

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95. Baffles can be mounted inside the tanks to:

A) provide partitions between individual segments of an integrated fuel tank

B) direct the fuel towards the fuel pumps

C) none of the above

D) prevent fuel sloshes

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96. Drain cocks are fitted:

A) to enable water to be drained from the system

B) between the pump and a selector

C) at the highest point in the system so that any fluid drained is not contaminated with water

D) at the lowest point in the system

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97. The fuel crossfeed system:

A) is only used in flight for fuel transfer from one tank to another

B) is only used to feed an engine from the tank of the opposite wing

C) allows feeding of any engine from any fuel tank

D) is only used on the ground for fuel transfer from one tank to another

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98. The flash point of a fuel is:

A) the temperature at which the viscosity of fuel changes suddenly.

B) the lowest temperature at which fuel produces sufficient vapour to be ignited by a small flame or spark

C) the boiling temperature of the fuel.

D) the temperature to which it must be heated in order to give off vapour which will burn continuously when brought into contact with a small flame.

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99. The types of fuel tanks used on most modern transport aircraft are:

A) Fixed built-in tanks

B) Combined fuel tanks

C) Integral tanks.

D) Cell tanks

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100. A fuel booster pump, which is used to provide positive fuel flow to the engine, can also be used for:

A) fuel jettison and fuel heating

B) fuel dumping and fuel jettison

C) fuel jettison and fuel transfer

D) fuel transfer and fuel heating

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101. Fuel pumps submerged in the fuel tanks of a modern jet aircraft are:

A) mechanically driven by the engine's accessory gearbox

B) electro-mechanical wobble pumps, with self-regulated pressure

C) centrifugal pumps, driven by an electric motor

D) removable only after the associated tank has been emptied

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102. In a compensated capacitance fuel contents system what happens to a fuel weight of 8000lbs if its volume increases by 5%?

A) Decreases by 5%.

B) Increases by 5%.

C) Remains the same

D) Increases by 5% for every degree rise in temperature.

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103. VAPOR LOCK is the phenomenon by which:

A) water vapour plugs are formed in the intake fuel line following the condensation of water in fuel tanks which have not been drained properly

B) heat produces vapour plugs in the fuel line

C) burnt gas plugs forming and remaining in the exhaust manifold following an overheat and thereby disturbing the exhaust

D) abrupt and abnormal enrichment of the fuel/air mixture following an inappropriate use of carburettor heat

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104. The vent pipe of an aircraft's fuel tank must not become blocked because:

A) pressure will fall in the tank when fuel is used

B) pressure will not change in the tank when fuel is used

C) pressure will rise in the tank when fuel is used

D) it is used to connect the fuel to the inlet manifold, so equalising the pressure

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105. What pressure does booster pump supply fuel at?

A) 300-500 psi.

B) 15-20 psi

C) 5-10 psi.

D) 3000-5000 psi

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106. When ice forms on the Vibrating Rod ice detector:

A) the frequency rises to the natural harmonic of the ice at approximately 40KHz

B) the frequency of vibration remains unchanged at 40KHz

C) the frequency of vibration increases above 40KHz

D) the frequency of vibration decreases below 40KHz.

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107. To prevent propeller elements overheating:

A) use only when the propellers are rotating

B) use only when in flight.

C) use only when all other services are switched off

D) carry out a load check before starting engines

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108. In flight airframe icing does not occur:

A) above 30 000 feet

B) above 35 000 feet

C) above 40 000 feet

D) above 25 000 feet

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109. Regarding carburettor ice, state the environmental caution areas for the formation of this type of ice.

A) Temperature between ÷ 5° C and + 18° C, visible moisture or relative humidity greater than 60 %.

B) Temperature less than 0° C, and clouds present

C) Temperature between + 5° C and ÷ 18° C, visible moisture or relative humidity greater than 60 %.

D) Temperature between + 5° C and 18° C and clouds present

110 / 655

110. Freezing point depressant (FPD) is supplied in two types:

A) Type 1 fluid (unthickened) - Type 2 fluid (unthickened)

B) Type 1 fluid (thickened) - Type 2 fluid (unthickened)

C) Type 1 fluid (thickened) - Type 2 fluid (thickened)

D) Type 1 fluid (unthickened) - Type 2 fluid (thickened)

111 / 655

111. The ice protection for propellers of modern turboprop aeroplanes works:

A) with anti-icing fluid

B) with hot air

C) pneumatically

D) electrically

112 / 655

112. The electrical supply to the propeller blades for de-icing purposes

A) is controlled to give an intermittent supply.

B) must be taken directly from the APU generator

C) is continuous to all blades

D) must only be selected on for short periods

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113. The accurate method of removing snow and ice that has accumulated on the aircraft during parking, is:

A) Hot water that melts the contamination

B) The aeroplane's own de-ice equipment for five minutes

C) Hot air from the engines

D) De-ice all surfaces with approved de-ice fluid.

114 / 655

114. The elements specifically protected against icing on transport aircraft are:

1. engine air intake and pod.
2. front glass shield.
3. radome.
4. pitot tubes and waste water exhaust masts.
5. leading edge of wing.
6. cabin windows.
7. trailing edge of wings.
8. electronic equipment compartment.
The combination regrouping all the correct statements is:

A) 1, 2, 3, 8

B) 1, 2, 5, 6

C) 1, 4, 5, 7

D) 1, 2, 4, 5

115 / 655

115. Ice detectors are used primarily to warn the crew:

A) that they are approaching airframe icing conditions

B) that airframe icing conditions exist

C) that engine icing conditions now warrant the initiation of the engine system

D) that they are approaching engine icing conditions

116 / 655

116. A typical electrical anti-icing/de-icing system would consist of the following components:

A) an uncontrolled frequency alternator, a cyclic timer and electrical elements bonded to the surfaces

B) an uncontrolled frequency alternator, a two speed cyclic timer and electrical elements bonded to the surfaces

C) none of the above

D) a controlled frequency alternator, and electrical elements bonded to the surfaces.

117 / 655

117. Usually, electric heating for ice protection is used on:

A) Wing and stabilizer leading edges

B) Engine intakes.

C) Pitot tubes

D) Pitot tubes and engine intakes

118 / 655

118. In order to prevent/eliminate ice build-ups on a pitot tube on light aircraft, the pilot can use:

A) a heating system consisting of an electric resistor inside the tube itself

B) anti-ice system using glycol-based anti-freeze liquid being sprayed onto the pitot tube

C) a heating system consisting of a hot air duct routed from the heat exchanger to the root of the pitot tube

D) a heating system consisting of an electric resistor element wrapped around the root of the tube

119 / 655

119. Fluid is delivered to a propeller by:

A) a slinger ring and pipes

B) a centrifugal slipper ring and pipes

C) integral passages within the propeller dome

D) a small reservoir contained within the spinner

120 / 655

120. When anti-icing fluid is applied to an aircraft, which of the following icing conditions would give the longest holdover times?

A) Freezing fog

B) Rain on a cold soaked wing

C) Frost.

D) Snow

121 / 655

121. Modern Turboprop aircraft are anti-iced by which method

A) thermal

B) electrica

C) mechanical.

D) none of the above

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122. The electrical power which is supplied to the propeller blades for de-icing purposes:

A) is continuously supplied to all propeller blades

B) must only be selected ON for short periods.

C) must be taken directly from the APU generator

D) is controlled to give an intermittent supply

123 / 655

123. Propeller electrical de-icing systems:

A) use a cyclic timer

B) transfer power to the elements via a commutator in DC systems

C) use only continuous loads to the elements

D) convert electrical energy to mechanical energy

124 / 655

124. An aircraft is to be de-iced and then enter the line up for departure. Which de-ice fluid will have the best holdover time at 0° C with precipitation:

A) type I fluid at 100% cold spray

B) type II fluid at 100% cold spray

C) a 50%/50% solution of type II fluid hot spray.

D) a 50%/50% solution of type I fluid hot spray

125 / 655

125. Generally, for large aeroplanes, electrical heating for ice protection is used on:

A) Slat leading edges

B) Pitot tubes

C) Fin leading edges

D) Elevator leading edges

126 / 655

126. The probe heater operates:

A) when the switch is ON and both engines are running

B) automatically, when the probe detects ice.

C) automatically, underneath a present temperature

D) automatically when airborne

127 / 655

127. The heating facility for the windshield of an aircraft is:

A) only used when hot-air demisting is insufficient.

B) used on a continual basis as it reduces the thermal gradients which adversely affect the useful life of the components.

C) harmful to the integrity of the windows in the event of a bird strike

D) used only at low altitudes where there is a risk of ice formation.

128 / 655

128. The effect of frost on an aircraft:

A) can be generally ignored

B) is to cause an increase in boundary layer energy and so delay the onset of the stall

C) has no significant effect on the aerodynamic contour or lift coefficient.

D) causes an increase in the surface roughness which in turn increases skin friction drag

129 / 655

129. Concerning electrically powered ice protection devices, the only true statement is:

A) On modern aeroplanes, electrically powered thermal devices are very efficient, therefore they only need little energy.

B) On modern aeroplanes, electrical power supply being available in excess, this system is often used for large surfaces de-icing

C) On modern aeroplanes, electrically powered thermal devices are used to prevent icing on small surfaces (pitot-static, windshield...)

D) On modern aeroplanes, electrically powered thermal devices are used as de-icing devices for pitot-tubes, static-ports, windshield...

130 / 655

130. Propeller blade heating elements are:

A) fitted to the complete leading edge.

B) fitted only to the thin outer sections where maximum ice accretion occurs.

C) fitted only to the thick inner section where minimum ice accretion occurs.

D) usually fitted to the thick section but sometimes a second element is fitted to a mid section

131 / 655

131. The hot rod ice detector:

A) cannot be seen at night

B) is heated at all times during flight

C) is automatically heated approximately every 2 minutes during flight

D) may be heated and illuminated by the pilot operating the appropriate switches

132 / 655

132. When an aircraft is de-iced prior to departure, if the temperature is 0° C in precipitation, which type of fluid and application method will provide the longest holdover period:

A) Type I fluid @ 100% cold spray application

B) Type I fluid diluted to 50% hot spray application

C) Type II fluid diluted to 50% hot spray application

D) Type II fluid @ 100% cold spray application

133 / 655

133. The methods used to provide de-icing in flight can be:

A) mechanical or pneumatic or fluid.

B) centrifugally forced or ram air heated

C) electrically heated or air heated or oil heated

D) pneumatic or thermal or fluid

134 / 655

134. In a bootstrap cooling system the supply air is first:

A) passed across an expansion turbine, then directly to the heat exchanger

B) compressed, then goes through a heat exchanger, and across an expansion turbine

C) passed across an expansion turbine, then compressed and passed through a heat exchanger

D) compressed, then passed across an expansion turbine through a heat exchanger

135 / 655

135. Engine bleed-air which is used for pressurisation of the cabin is:

A) warmer than cabin temperature

B) its temperature is relatively high and must be cooled by a heat exchanger unit just before it enters the passenger cabin

C) its temperature is approximately the same as the outside air temperature

D) colder than cabin temperature

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136. In the air cycle system the air is cooled down by expansion:

A) of Freon in the turbine

B) in the turbine

C) of Freon in a heat exchanger

D) in a pressure relief valve

137 / 655

137. Which is the most suitable relative humidity for an environmental control system to maintain in an aircraft?

A) 80%.

B) 10%.

C) 30%.

D) 60%.

138 / 655

138. In an air cycle type air conditioning system, reduction of air temperature and pressure is achieved by:

A) a compressor

B) an evaporator

C) a condenser.

D) an expansion turbine

139 / 655

139. A Vapor Cycle Cooling system may be fitted to enhance the cooling cycle of an aircraft air conditioning system. On leaving the evaporator, in the correct sequence, which components does the gas pass through?

A) Liquid Receiver and Compressor

B) Compressor and Condenser

C) Condenser and Compressor

D) Condenser, Liquid Receiver and Expansion valve

140 / 655

140. When air is compressed for pressurization purposes, the percentage oxygen content is:

A) dependent on the degree of pressurization

B) unaffected

C) increased

D) decreased

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141. The purpose of a spill valve in a cabin air supply system is:

A) to spill overboard excess air delivered at high altitudes

B) to provide conditioned air distribution throughout the passenger cabin

C) to spill overboard excess air delivered at low altitudes

D) to provide an emergency source of outside air in case of a complete failure of all bleed valves

142 / 655

142. The maximum differential pressure of a transonic transport category airplane is approximately

A) 3.5 psi.

B) 13.5 psi.

C) 9.0 psi.

D) 15.5 psi

143 / 655

143. If the forward oil seal in an axial flow compressor fails, compressed air:

A) becomes highly flammable

B) will not be contaminated if synthetic oil was used

C) will not be contaminated if mineral oil was used

D) will be contaminated with oil

144 / 655

144. An ACM produces a drop in temperature by:

A) directing compressed air into a heat exchanger

B) by-passing the air conditioning heating system

C) a primary and secondary heat exchanger.

D) expanding hot air across a turbine which is driving a compressor

145 / 655

145. Inward vent valves operate when:

A) pressurising after a rapid climb

B) depressurising after descent

C) cabin altitude exceeds aircraft altitude

D) aircraft altitude exceeds cabin altitude

146 / 655

146. Cabin differential pressure is the pressure difference between

A) local ambient pressure and mean sea level pressure

B) cabin pressure and ambient pressure

C) 8,000ft pressure altitude and cabin pressure

D) ISA conditions and aircraft altitude.

147 / 655

147. The turbine in a cold air unit (air cycle machine):

A) drives the compressor which provides pressurisation

B) drives the compressor in the unit and causes a pressure increase in the conditioning air

C) drives the compressor in the unit, creating a temperature drop in the conditioning air

D) increases the pressure of the air supply to the cabin.

148 / 655

148. Under normal flight conditions, cabin pressure is controlled by:

A) pressurisation duct relief valve(s).

B) regulating the discharge of air through the outflow valve(s).

C) engine rpm

D) inward relief valve(s).

149 / 655

149. In level pressurised flight the outflow valve:

A) alternates between fully open and closed

B) remains closed.

C) adjusts to provide constant flow and is normally partially open

D) opens to increase air conditioning

150 / 655

150. Typically, icing does not occur above about...

A) 8000 ft.

B) 40000 ft.

C) 12000 ft.

D) 25000 ft.

151 / 655

151. When an aircraft has reached a flight level where pressure differential is at its maximum, the pressure controller:

A) opens the outflow valves so that all pressurising air is spilled overboard

B) switches off the cabin air supply

C) maintains a constant mass flow

D) closes the outflow valve immediately

152 / 655

152. Cabin air for modern airplanes is usually taken from:

A) the low pressure compressor and from the high pressure compressor if necessary

B) the high pressure compressor

C) the second fan stage

D) the low pressure compressor

153 / 655

153. An air cycle cooling system uses the principle of:

A) expanding air through a turbine and dissipating heat in a heat exchanger

B) heat dissipation by primary, secondary and tertiary heat exchangers

C) gas pressure reduction and heat radiation

D) heat dissipation by evaporation

154 / 655

154. A cabin humidifier is sometimes used:

A) to prevent corrosion

B) at low altitude

C) on the ground in high ambient temperatures

D) at high altitude.

155 / 655

155. The pressure relief valve operates

A) at system pressure

B) below system pressure in an emergency

C) above system pressure when the normal relief device fails

D) to maintain optimum cabin pressurisation.

156 / 655

156. In a climatisation system, temperature control is achieved by:

A) regulating the ambient airflow through the heat exchanger

B) controlling the humidity of the air supply

C) controlling the air pressure

D) regulating the amount of air by-passing the cooling system

157 / 655

157. An aircraft with a pressurized cabin flies at level 310. Following a malfunction of the pressure controller, the outflow valve runs to the open position.

Given:

VZc = Cabin rate of climb indication

Zc = Cabin pressure altitude

DELTA P = Differential pressure

This will result in a:

A) VZc increase Zc increase DELTA P decrease

B) VZc increase Zc increase DELTA P increase

C) VZc decrease Zc increase DELTA P decrease

D) VZc decrease Zc decrease DELTA P increase

158 / 655

158. The term " pressure differential" can be defined as the pressure difference between:

A) the inside and the outside of the aircraft

B) the pressure at sea level and at the altitude at which the aircraft is flying

C) the pressure of the cabin and the pressure of any non-pressurised zone.

D) the cabin pressure level and it's rate of change

159 / 655

159. Pressurisation control ensures that:

A) at normal flying altitudes the cabin altitude is at or below 8,500ft

B) at normal flying altitudes the cabin altitude is at or below 8,000ft

C) at normal flying altitudes the cabin altitude is at or below 10,000ft

D) at normal flying altitudes the cabin altitude is at or below 12,000ft

160 / 655

160. What must be isolated when carrying out a cabin pressurisation ground tests?

A) pressure relief valve.

B) pressure regulator or controller

C) pitot static flow valve

D) pressure discharge valve

161 / 655

161. Essential information whether to use the engine anti-ice system or not, is?

A) Ram air temperature, only

B) Reported temperature when airborne, and ram air temperature when on ground

C) Reported temperature, always

D) Reported temperature when on ground, and ram air temperature when airborne

162 / 655

162. A heat exchanger functions by:

A) passing charge air through ducts and cool air around ducts

B) combining ram and charge air

C) mixing the various vapours inside the heat exchanger

D) removing the static charge

163 / 655

163. Cabin altitude in pressured flight is:

A) the altitude corresponding to cabin pressure regardless of aircraft height

B) altitude at which cabin pressure equals ambient pressure

C) is presented on a second needle on the aircraft altimeter

D) altitude corresponding to cabin pressure in relation to MSL ISA conditions

164 / 655

164. Assuming cabin differential pressure has attained the required value in normal flight conditions, if flight altitude is maintained:

A) the pressurisation system ceases to function until leakage reduces the pressure

B) a constant mass air flow is permitted through the cabin

C) the outflow valves will move to the fully closed position

D) the outflow valves will move to the fully open position

165 / 655

165. An aircraft with a pressurized cabin is settled at its cruise level. During the flight, a malfunction of the pressure controller is detected by the crew and the cabin rate of climb indicator reads -200ft/min.

Given that:

DELTA P = Differential pressure

Zc = Cabin altitude

A) The crew has to intermittently cut off the incoming air flow in order to maintain a zero Zc.

B) DELTA P will rise up to its maximum value, thus causing the safety relief valves to open

C) The aircraft has to climb to a higher flight level in order to reduce Zc to its initial value

D) A descent must be initiated to prevent the oxygen masks dropping when Zc reaches 14000ft

166 / 655

166. A humidifier is fitted to:

A) increase the moisture content in the air when operating at high altitude

B) filter the air

C) extract the moisture content in the air

D) to ensure the cabin air is saturated at high altitude

167 / 655

167. The aircraft inhibiting switch connected to the A/C landing gear:

A) allows the aircraft to be pressurised on the ground

B) stops pressurising on the ground and ensures that there is no pressure differential.

C) cancels out the safety valve on the ground

D) ensures that the discharge valve is closed

168 / 655

168. Cabin altitude in pressurised flight is:

A) the altitude at which cabin pressure equals ambient pressure

B) always equal to 8000ft

C) the altitude corresponding to cabin pressure regardless of aircraft height

D) the altitude at which cabin temperature equals ambient temperature

169 / 655

169. The function of an air cycle machine is to:

A) pump the conditioned air into the cabin

B) remove the water from the bleed air

C) cool the bleed air

D) decrease the pressure of the bleed air.

170 / 655

170. In normal operation, the maximum cabin altitude for a large passenger aircraft is:

A) 10.000ft

B) 20.000ft

C) 14.000ft

D) 8.000ft

171 / 655

171. With a gas turbine engine, should engine anti-icing be selected " ON" :

A) whenever the igniters are on

B) whenever the ice detector system warning light comes on

C) whenever the TOAT is +10° C or below and it is raining

D) whenever the IOAT is +10° C or below and the air contains visible moisture

172 / 655

172. When taking off and when pressurisation is initiated, cabin rate of climb will show:

A) a continuous gradual decrease

B) an increase

C) a continuous gradual increase

D) a decrease

173 / 655

173. During a normal take-off and climb:

A) cabin pressure rises more slowly than atmospheric pressure

B) the cabin pressure falls at a maximum rate of 0.4ft/sec.

C) cabin pressure falls more slowly than atmospheric pressure

D) the pressurisation system is ineffective until altitude exceeds 8000m

174 / 655

174. The power source for hot air in de-ice / anti ice systems on jet A/C is:

A) turbo compressors

B) ram air, heated via a heat exchanger

C) bleed air from the engines' compressor

D) the APU

175 / 655

175. In a pressurized aircraft whose cabin altitude is 8000 ft, a crack in a cabin window makes it necessary to reduce the differential pressure to 5 psi. The flight level to be maintained in order to keep the same cabin altitude is:

A) FL 230

B) FL 340.

C) FL 180

D) FL 280.

176 / 655

176. Some pressure controllers have a ditching control. When activated:

A) the airplane enters into a vertical dive

B) cabin is depressurised immediately

C) all outflow valves are closed

D) water is allowed to enter special flotation devices

177 / 655

177. Which statement is true about the pressurisation system?

A) The pressurisation system always uses pressurised air stored in bottles to pressurise the cabin

B) A pressurisation system is not required by law for flights below 31000ft

C) Partial oxygen pressure in the cabin is independent of cabin altitude

D) To maintain a constant pressure in the cabin, the total amount of airflow from the air conditioning system is equal to the mass flow passing through the outflow valve and small leaks (e.g. exit doors).

178 / 655

178. Safety valves operate:

A) whenever differential pressure exceeds a certain value

B) whenever maximum negative pressure differential is reached

C) whenever differential pressure exceeds 6.9 psi

D) whenever differential pressure exceeds 7.9 psi

179 / 655

179. De-icer boots consist of layers of... and... between which are disposed flat inflatable tubes... at the ends.

A) plastic, rubber, open.

B) natural rubber, rubberised fabric, closed

C) natural rubber, nylon, closed

D) nylon, steel, closed.

180 / 655

180. Safety valves and inward relief valves operate:

A) To control cabin altitude

B) To control cabin altitude in conjunction with the cabin pressure gauge.

C) When an aircraft ditches

D) To control maximum positive and negative pressure differentials

181 / 655

181. The function of spill valves is to control:

A) cabin temperature

B) cabin pressure

C) cabin pressure differential

D) hydraulic fluid pressure

182 / 655

182. The rate of change of cabin pressure should be kept to the minimum. Is this more important:

A) in periods when the dehumidifier is in use

B) in cruise.

C) in descent

D) in climb

183 / 655

183. The pneumatic actuators are normally of the:

A) rotary type only

B) linear damped type

C) linear undamped type

D) linear and rotary type

184 / 655

184. In a Bootstrap Bleed Air air-conditioning system, if the cabin temperature is reduced:

A) pressure at the outlet of the cold air unit will increase

B) pressure at the cold air unit compressor inlet will increase

C) the boot strap compressor rpm will increase

D) the flow rate at the mass flow controller outlet will increase

185 / 655

185. Cabin altitude means the:

A) flight level the aircraft is flying at

B) flight level altitude at maximum differential pressure

C) difference in height between the cabin floor and ceiling

D) cabin pressure expressed as altitude

186 / 655

186. The mass flow delivery from the engine driven mechanical compressors is controlled by:

A) spill valves.

B) choke valves

C) automatic control devices

D) engine speed variations

187 / 655

187. Ditching Cocks are operated:

A) for rapid depressurisation

B) to direct pressure into flotation bags

C) automatically when the soluble plugs dissolve

D) to shut all outflow valves

188 / 655

188. " Conditioned" air is air that has:

A) had any moisture removed from it

B) been controlled in respect of temperature and pressure

C) had the oxygen content reduced

D) had the oxygen content increased

189 / 655

189. Rate of change of cabin altitude is shown on a:

A) aircraft vertical speed indicator (VSI).

B) pitot/static indicator

C) cabin altitude rate of change indicator

D) altimeter

190 / 655

190. If in cruise at 30000ft the cabin altitude is adjusted from 4000ft to 6000ft:

A) cabin differential will not change

B) cabin differential will decrease

C) cabin differential will increase

D) none of the above - pressurization level can only be pre-selected on the ground before takeoff

191 / 655

191. A turbo-fan cold air unit will:

A) not affect the charge air pressure

B) increase charge air pressure whilst causing the temperature to drop in the heat exchanger

C) cause a pressure drop as well as an associated temperature drop in the charge air.

D) decrease charge air pressure whilst causing the temperature to rise in the heat exchanger.

192 / 655

192. A pneumatic de-ice system should be operated..

A) When there are approximately 5 cm of ice on leading edges

B) When there is approximately 1,5 cm of ice on leading edges

C) Only at take-off and during approach

D) When entering areas with icing conditions

193 / 655

193. In an aircraft air conditioning system the air cannot be treated for:

A) purity

B) humidity

C) temperature

D) pressure

194 / 655

194. What controls cabin pressurisation?

A) Inflow valve

B) Engine bleed valve

C) Outflow valve

D) ECS pack mass flow controller

195 / 655

195. If in flight a door warning light illuminates:

A) no action is required unless the warning is accompanied by a loss of cabin pressure

B) none of the above

C) crew members must be extremely careful when checking an inward opening plug type door

D) a crew member should make a careful check of the door to make certain that the door locking bolts are correctly extended

196 / 655

196. When would negative differential be exceeded?

A) During a ground pressure run.

B) When changing to manual operation

C) Rapid descent when aircraft descends below cabin altitude

D) Rapid ascent when aircraft climbs

197 / 655

197. In jet aeroplanes the 'thermal anti-ice system' is primarily supplied by:

A) bleed air from the engines

B) the APU

C) ram air, heated via a heat exchanger

D) turbo compressors

198 / 655

198. With reference to a vapour cycle cooling system, which statement is correct:

A) This system requires mechanical energy for operation

B) All of the above

C) Vapour cycle cooling systems have a greater cooling capacity than air cycle systems

D) This system uses a refrigerant fluid in a closed circuit

199 / 655

199. Cabin differential pressure means the pressure difference between:

A) cabin pressure and ambient air pressure at MSL

B) cabin pressure and ambient air pressure

C) cockpit and passenger cabin

D) actual cabin pressure and selected pressure

200 / 655

200. Choke valves in a mechanically driven cabin air compressor provide extra heating by:

A) requiring higher compressor output pressure

B) requiring lower compressor input pressure

C) requiring higher compressor input pressure

D) requiring lower compressor output pressure

201 / 655

201. The boots of a pneumatic de-icing system are normally made of:

A) plastic

B) porous metal

C) synthetic rubber

D) neoprene rubber.

202 / 655

202. To maintain a steady and constant airflow regardless of altitude or cabin pressure:

A) a duct relief valve is installed

B) a flow controller is installed

C) a thermostatic relief valve is installed

D) a thermodynamic relief valve is installed

203 / 655

203. The term " pressurisation cycle" means:

A) the frequency in Hertz the pressure cycles from the roots blowers enter the fuselage

B) air discharged from the fuselage, above 15 psi

C) air introduced into a fuselage under pressure until the time the air is released

D) air introduced into a fuselage under pressure only.

204 / 655

204. After take-off during a normal pressurised climb:

A) cabin ROC is the same as the ambient ROC

B) the cabin ROC is less than ambient ROC

C) the differential pressure is constant

D) the cabin ROC is more than ambient ROC.

205 / 655

205. On landing, the cabin pressure is equalized with atmospheric pressure by the operation of:

A) squat switches which open the dump valves at touch down

B) alighting gear down selection

C) the alighting gear reaching the fully extended position

D) squat switches which open the outflow or discharge valves at touch down

206 / 655

206. At maximum cabin differential pressure the:

A) discharge valve opens

B) negative pressure relief valve opens

C) the outflow valve drives to fully closed position

D) engine bleed valves close

207 / 655

207. In a cabin air conditioning system, equipped with a bootstrap, the mass air flow is routed via the:

A) compressor outlet of the cold air unit to the primary heat exchanger inlet.

B) secondary heat exchanger outlet to the turbine inlet of the cold air unit

C) turbine outlet of the cold air unit to the primary heat exchanger inlet

D) secondary heat exchanger outlet to the compressor inlet of the cold air unit

208 / 655

208. At max differential phase, the discharge valve is:

A) partly open.

B) controlled manually by the pilot

C) open.

D) closed

209 / 655

209. State the function of a heat exchanger:

A) Assist the battery on a cold day (hot battery)

B) Cooling or heating of a fluid through convection and conduction, without mixing the fluids

C) Removing static charges from conductive fluids

D) Mixing ram air and cabin air.

210 / 655

210. The cabin heating supply in a heavy jet transport aircraft is obtained from

A) hot air coming from the engine's turbines

B) an electrical heater system

C) a fuel heater system

D) hot air coming from the engine's compressors

211 / 655

211. If the cabin pressure increases in level flight, the cabin VSI shows:

A) a positive rate of climb

B) no change unless the aircraft climbs

C) no change

D) a negative rate of climb.

212 / 655

212. A pressurisation circuit (normal operation) is designed so that the:

A) outflow valve operates after the safety valve opens

B) safety valve operates when the system has stabilised

C) outflow valve operates before the safety valve opens

D) outflow valve operates in combination with the safety valve

213 / 655

213. The pneumatic ice protection system is mainly used for:

A) propellers

B) wings

C) engine intakes

D) pitot tubes.

214 / 655

214. An aircraft with pressurised cabin has maximum cabin altitude of 8000 feet, which equals 10.9 PSI. Present flight altitude is 30.000 feet, which equals 4.36 PSI. Pressure at sea level equals 14.7 PSI. Calculate the difference pressure that influence the cabin structure:

A) 4.36 psid

B) 6.54 psid

C) 10.9 psid

D) 10.34 psid.

215 / 655

215. One advantage of a pneumatic system is:

A) leaks can be easily detected

B) no return lines or pipes are required

C) the reservoirs used are of lighter construction

D) air is considered as being virtually incompressible

216 / 655

216. If the cabin altitude rises (aircraft in level flight), the differential pressure:

A) remains constant

B) Increases

C) may exceed the maximum permitted differential unless immediate preventative action is taken.

D) Decreases

217 / 655

217. The rate of change of cabin pressure should be kept to the minimum. This is more important:

A) during descent

B) the same importance during climb and descent

C) during the climb

D) during the initial climb

218 / 655

218. Would you operate the flying controls during a cabin pressurisation ground test?

A) Yes.

B) Continuously

C) Occasionally

D) No

219 / 655

219. During level flight at a constant cabin pressure altitude (which could be decreased, even at this flight level), the cabin outflow valves are:

A) At the pre-set position for take-off

B) fully closed until the cabin climbs to a selected altitude

C) Partially open

D) Fully closed until the cabin descends to a selected altitude

220 / 655

220. When pressurising the cabin of an aircraft, the cabin pressure controller operates the:

A) outflow valve

B) differential valve

C) discharge valves

D) dump valves

221 / 655

221. If an aircraft is descending, what will happen to the cabin pressure differential?

A) it will remain constant until the aircraft reaches 8000 ft

B) it will reduce

C) it will remain constant

D) it will increase

222 / 655

222. Most of the cabin pressurisation systems have two modes of operation:

A) The differential mode and the pressure mode

B) The differential pressure and the constant pressure mode

C) The isobaric mode and the constant pressure differential mode

D) The cabin mode and the external mode

223 / 655

223. If the discharge or outflow valve closes:

A) the safety valve would limit the positive pressure difference

B) pressure will drop inside the cabin

C) the inward relief valve would assume control.

D) the safety relief valve would limit the negative pressure difference

224 / 655

224. The air-cycle cooling system produces cold air by:

A) Extracting heat energy across an expansion turbine.

B) Passing air through cooling coils than contain a refrigerant

C) Passing heated air through a compressor

D) Routing conditional air through the cooling fan.

225 / 655

225. The main elements of a vapour cycle cooling system are?

A) compressor, condenser, dryer, expansion valve, evaporator

B) compressor, dryer filter, distribution nozzles

C) reservoir, compressor, expansion valve, evaporator

D) turbine, water separator, heat exchanger, compressor.

226 / 655

226. During normal descent, the discharge valve (outflow valve) position is:

A) at a position pre-set before take-off.

B) partially open

C) fully open

D) closed until selected altitude is reached

227 / 655

227. In a climatisation system, an air to air heat exchanger is provided to:

A) increase the mass air flow

B) provide an emergency ram air supply

C) reduce the air supply temperature

D) increase the air supply pressure

228 / 655

228. Assume that during cruise flight with air-conditioning packs ON, the outflow valve(s) would close. The result would be that:

A) the air supply would automatically be stopped

B) the pressure differential would go to the maximum value

C) the skin of the cabin would be overstressed

D) the cabin pressure would become equal to the ambient outside air pressure

229 / 655

229. The vapour cycle cooler works on the principle of changing:

A) liquid into vapour

B) vapour into liquid

C) vapour into gas.

D) gas into liquid

230 / 655

230. In pressurised aircraft, temperature control is mainly achieved by:

A) varying cabin pressure

B) adding heat to the bleed air.

C) adding cold ram air to the cabin

D) extracting heat from bleed air

231 / 655

231. Concerning the sequential pneumatic impulses used in certain leading edge de-icing devices, one can affirm that:
1. They prevent ice formation.
2. They are triggered from the flight deck after icing has become visible.
3. A cycle lasts more than ten seconds.
4. There are more than ten cycles per second.
The combination which regroups all the correct statements is:

A) 2 - 3

B) 2 -4

C) 1 - 3

D) 1 - 4

232 / 655

232. What is the purpose of the duct relief valve?

A) To protect the undercarriage bay

B) To prevent excess cabin temperature.

C) To relieve excess pressure to compressor return line

D) To prevent damage to the pneumatic ducts.

233 / 655

233. Water collected by the water separator may be sprayed into the ram air duct. This has the effect of:

A) increasing the efficiency of the heat exchanger(s) through condensation cooling

B) increasing the efficiency of the heat exchanger(s) through evaporation cooling

C) increasing the efficiency of the heat exchanger(s) through sublimation cooling

D) none of the above

234 / 655

234. In an air conditioning system, a pack valve is used to:

A) prevent negative differential pressure

B) control the mass air flow

C) bleed air from the engines

D) connect the pneumatic source to the air cycle system inlet.

235 / 655

235. In a bootstrap air cooling system the secondary heat exchanger:

A) further reduces temperature of the air supply from the primary heat exchanger

B) raises the heat of the turbine inlet air to increase the pressure drop across the turbine

C) removes heat from the compressor discharge air

D) cools the turbine discharge air before it enters the cabin

236 / 655

236. Main cabin temperature is:

A) controlled automatically, or by flight crew selection

B) not controllable at the maximum cabin differential pressure

C) Only controllable at maximum cabin differential pressure

D) controlled by individual passenger

237 / 655

237. A typical MP pneumatic main system pressure would be:

A) 3,000 psi

B) 1,000 psi.

C) 400 psi.

D) 3,500 psi.

238 / 655

238. The cabin altitude selector on the flight deck works in conjunction with:

A) the inward/outward vent valve

B) the cabin pressure control valve

C) the cabin pressure discharge valve

D) the cabin safety valve.

239 / 655

239. The water separator of an air-conditioning unit is located at the cooling unit:

A) outlet and uses an evaporation process

B) inlet and uses a centrifugal process

C) inlet and uses an evaporation process

D) outlet and uses a centrifugal process.

240 / 655

240. A pressurisation system works by:

A) does not start until an altitude of 8,000ft has been reached

B) supplying hot gases from the engine exhaust unit to the mass flow control system

C) essentially constant input mass flow and variable output

D) essentially constant input mass flow and variable output

241 / 655

241.

The pneumatic system accumulator is useful:

A) to eliminate the fluid flow variations

B) to offset for the starting of some devices

C) to eliminate the fluid pressure variations

D) in emergency cases

242 / 655

242. In level pressurised flight does the outflow valve:

A) close.

B) adjust to provide constant flow, and is normally almost closed.

C) open to increase air conditioning

D) adjust to provide constant flow, and is normally partially open

243 / 655

243. A drop in temperature by a cold air unit is produced by:

A) expanding the hot air in a compressor, increasing pressure and driving the unit's turbine

B) expanding the hot air in a turbine, reducing pressure and driving the unit's freon refrigeration unit

C) expanding the hot air in a compressor, increasing pressure and driving the unit's freon refrigeration unit

D) expanding the hot air in a turbine, reducing pressure and driving the unit's compressor

244 / 655

244. A cabin pressurisation system is often installed onboard turbine powered aircraft. If installed, it normally has:

A) Three modes of operation

B) One mode of operation

C) Four modes of operation

D) Two modes of operation

245 / 655

245. In a manually operated system, the cabin altitude rate of change is normally controlled by:

A) a rate of change selector

B) the duct relief valve when operating at the maximum cabin differential pressure

C) the difference between the barometric pressure selected on the cabin pressure controller and ambient barometric pressure

D) the difference between the altitude selected on the cabin pressure controller and the aeroplane altitude

246 / 655

246. The picollo duct is part of the:

A) wing thermal anti-icing system

B) bleed-air system

C) secondary structure of the wing

D) slat track mechanism

247 / 655

247. The term " cabin pressure" applies when an aeroplane:

A) has the means to maintain the cabin pressure at a higher level than the ambient pressure

B) is only pressurized in the area of the control cabin

C) has the ability to maintain a constant cabin altitude at all flight altitudes

D) has the ability to maintain constant any cabin differential pressure

248 / 655

248. In a Bleed Air (Bootstrap) air conditioning system, where is the water extractor located?

A) downstream of the cold air unit compressor

B) upstream of the cold air unit turbine

C) upstream of the cold air unit compressor

D) downstream of the cold air unit turbine

249 / 655

249. If pressurisation is selected before take-off the cabin rate of change indicator indicates

A) a rate of descent

B) a rate of climb

C) 14,7 psi

D) zero

250 / 655

250. The disadvantage of a HP pneumatic system when compared to a comparable hydraulic system would be:

A) all of the above

B) lacks provisions for standby operation

C) higher maintenance costs

D) air leaks are difficult to locate

251 / 655

251. The term " Bootstrap" , when used to identify a cabin air conditioning and pressurisation system, refers to the:

A) cold air unit (air cycle machine) arrangement

B) charge air across the inter-cooler heat exchanger

C) means by which pressurisation is controlled

D) source of the charge air

252 / 655

252. Air for conditioning and pressurisation is taken from:

A) the engine compressor or cabin compressor

B) the engine turbine or cabin compressor

C) the engine compressor or ram air turbine

D) a ram air turbine

253 / 655

253. With regard to the pneumatic mechanical devices which afford protection against the formation of ice, the only correct statement is:

A) The pneumatic mechanical device is used a lot on modern aircraft as it is inexpensive and easy to maintain.

B) The inflatable de-ice boots of the pneumatic mechanical device are arranged perpendicular to the leading edges.

C) The pneumatic mechanical device can only be used as an anti-icing device.

D) The pneumatic mechanical device can only be used as a de-icing device

254 / 655

254. What is the purpose of the pack cooling fans in the air conditioning system?

A) Supplying the heat exchangers with cooling air during cruise flight

B) Cooling of the APU compartment

C) Supplying the Passenger Service Unit (PSU) with fresh air

D) Supplying the heat exchangers with cooling air during slow flights and ground operation

255 / 655

255. In which sequence does the refrigerant of a vapour cycle refrigeration system pass through the different components?

A) compressor, condenser, expansion valve, evaporator

B) compressor, condenser, evaporator, expansion valve

C) compressor, evaporator, expansion valve, condenser

D) condenser, evaporator, reservoir, expansion valve

256 / 655

256. If the pressure in the cabin tends to become lower than the outside ambient air pressure the:

A) outflow valve open completely

B) negative pressure relief valve will open.

C) air cycle machine will stop

D) negative pressure relief valve will close

257 / 655

257. Assuming cabin differential pressure has reached the required value in normal flight conditions, if flight altitude and air conditioning system setting are maintained:

A) the mass air flow through the cabin is constant

B) the pressurisation system ceases to function until leakage reduces the pressure

C) the outflow valves will move to the fully open position

D) the outflow valves will move to the fully closed position

258 / 655

258. Which of the following statements are correct?

A) Water extracted by the de-humidifier unit is used by the humidifier to give the required cabin humidity

B) The water extractor is upstream of the air cooling unit to prevent moisture freezing in the system.

C) The humidifier employs water from the aircraft domestic supply, which is passed through a venturi to increase relative humidity

D) Water extractor units are only used at very high altitudes

259 / 655

259. In level pressurised flight, the outflow valve:

A) is partially open and regulates cabin pressure

B) alternates between fully open and closed.

C) open to increase mass flow from the packs.

D) is closed

260 / 655

260. In a turbo cooler system, the cooling air is:

A) cabin air.

B) compressor air

C) ram air

D) engine by-pass air

261 / 655

261. The anti-ice or de-icing system which is mostly used for the wings of modern turboprop aeroplanes is:

A) Pneumatic boots

B) Fluid de-icing.

C) Thermal anti-icing

D) Electrical heating.

262 / 655

262. The primary heat exchanger in a turbo-compressor cooling system:

A) heats the cold air before it enters the passenger cabin

B) cools the bleed air before it enters the passenger cabin

C) pre-cools bleed air before it enters the turbine

D) pre-cools bleed air before it enters the compressor

263 / 655

263. The airflow from the air conditioning packs to the cabin is:

A) at a variable rate depending on the cruising altitude

B) at a constant rate regardless of altitude

C) at a variable rate depending on the cabin altitude

D) regulated by the air mix valves depending on the cabin pressure differential

264 / 655

264. A thermal wing de-icing system:

A) relies on heat generated by the kinetic heating effect of the airflow

B) can use air taken from the engine compressor

C) feeds the engine exhaust through the leading edge ducts only.

D) feeds hot air along the complete upper wing surface.

265 / 655

265. The tubes in the de-ice boots are usually inflated alternately. Why?

A) Because alternate inflation of de-ice boot tubes keeps disturbance of the airflow to minimum

B) Because alternate inflation of de-ice boot tubes relieves the load on the airpump

C) Because alternate inflation of de-ice boot tubes does not affect the balance of the aircraft

D) Because alternate inflation of de-ice boot tubes relieves the strain on the attack point

266 / 655

266. How is the (charge) air cooled in a bootstrap (turbo-compressor) system?

A) By passing it through the fuel heater

B) By expanding over turbine driving compressor

C) Via an air cooled radiator

D) By expanding over turbine

267 / 655

267. Normal cabin ventilation and pressurisation is achieved by a:

A) modulating bleed air valve / pressure controller

B) modulating bleed air valve / discharge valve combination

C) pressure controller / inlet valve combination

D) pressure controller / discharge valve combination

268 / 655

268. The purpose of a ditching control is to:

A) direct pressurisation air to the flotation bags

B) achieve rapid depressurisation

C) open the outflow valve(s).

D) close the outflow valve(s).

269 / 655

269. In the case of a thermal de-icing system over temperature, this indicated by:

A) warning lights

B) temperature gauges

C) a buzzer

D) yellow flags

270 / 655

270. Under normal conditions (JAR 25) the cabin pressure altitude is not allowed to exceed:

A) 10.000 ft

B) 4.000 ft

C) 8.000 ft

D) 6.000 ft

271 / 655

271. For the pressurisation system, bleed air is used to drive the turbine of an air cycle machine in order to:

A) drive the pressurisation system

B) decrease the air velocity

C) decrease the bleed air pressure

D) decrease the bleed air temperature

272 / 655

272. High pressure pneumatic services would typically be:

A) wheel brakes only

B) landing gear extension and retraction, flap extension and retraction

C) landing gear emergency lowering only

D) landing gear and flap extension and retraction, main wheel brakes, piston engine radiator air shutter control

273 / 655

273. If pressurisation air supply comes from the compressor of the engine, an oil leak from the compressor bearings will:

A) not affect the air as it is vented overboard

B) not contaminate the air

C) contaminate the air

D) not affect the quality of the air as it is automatically filtered

274 / 655

274. In the cruise at 30,000ft the cabin altitude is adjusted from 4,000ft to 6,000ft:

A) cabin differential will increase

B) cabin differential will decrease

C) nil.

D) cabin differential will not be affected

275 / 655

275. What is the purpose of the duct relief valve:

A) to relieve excess pressure to compressor return line

B) to prevent damage to the ducts

C) to protect the undercarriage bay

D) to ensure the compressor pressure is regulated

276 / 655

276. A cold air unit produces a drop in temperature by:

A) a primary and secondary heat exchanger

B) expanding hot air across a turbine which is driving a compressor

C) directing compressed air into a heat exchanger

D) by-passing the air conditioning heating system

277 / 655

277. If the maximum operating altitude of an airplane is limited by the pressurized cabin, this limitation is due to the maximum:

A) Positive cabin differential pressure at maximum cabin altitude

B) Positive cabin differential pressure at maximum operating ceiling.

C) Negative cabin differential pressure at maximum operating ceiling

D) Negative differential pressure at maximum cabin altitude

278 / 655

278. If pressure is manually controlled:

A) care should be taken to ensure climb/descent rates are safe

B) an extra member is required to monitor system operation

C) climb rate could not be maintained

D) the climb rate would be maintained automatically

279 / 655

279. When the destination field elevation is set on the pressurisation control system:

A) the outflow valves are driven to the full open position automatically to equalise cabin and outside air pressure

B) the barometric controller adjusts cabin pressure to approximately 0.1psi above ambient pressure (at destination).

C) the outflow valves are driven to the full closed position to prevent contaminants entering the cabin through the outflow valves

D) the barometric controller adjusts cabin pressure to approximately 0.1psi below ambient pressure (at destination)

280 / 655

280. The pack cooling fan provides:

A) cooling air to the primary and secondary heat exchanger during slow flight and ground operation

B) air to the eyeball outlets at the Passenger Service Unit (PSU).

C) cooling air to the primary and secondary heat exchanger during cruise

D) cooling air to the pre-cooler

281 / 655

281. In the event of failure in one of the cabin air supplies, loss of cabin pressure is prevented by:

A) an automatic stand-by air supply

B) the NRVs in the delivery duct closing

C) the NRVs in the delivery duct opening

D) providing an alternative air supply

282 / 655

282. An aircraft climbs from sea level to 16,000 ft at 1,000ft per min, the cabin pressurisation is set to climb at 500ft per min to a cabin altitude of 8,000ft. The time taken for the cabin to reach 8,000ft is:

A) three times the time it takes the aircraft to reach 16,000ft

B) twice the time it takes the aircraft to reach 16,000ft

C) half the time it takes the aircraft to reach 16,000ft

D) the same time as it takes the aircraft to reach 16,000ft.

283 / 655

283. A typical refrigerant used in a vapour cycle cooling system is:

A) CO2

B) Ozone

C) Freon.

D) CO

284 / 655

284. A combustion heater works on the principle of:

A) tapping hot gases from the engine exhaust system and passing them through a heat exchanger

B) passing ram air over an active fuel burning heater and then to the cabin.

C) fuel choke differential.

D) passing ram air over the engine exhaust system to the cabin via a plenum chamber

285 / 655

285. Cooling in a vapour cycle cooler is achieved by converting

A) vapour into liquid.

B) liquid into vapour

C) gas into liquid

D) vapour into gas

286 / 655

286. A combustion heater system is normally supplied from?

A) An inflammable gas from a pressurised tank

B) Oil from the hydraulic system

C) An inflammable mixture for this particular purpose

D) Fuel from the aircraft fuel system

287 / 655

287. An engine driven air conditioning blower system will normally include in addition to the blower:

A) a mass flow controller, choke heat valve, silencer

B) a choke heat valve, silencer.

C) a mass flow controller, spill valves, choke heat valve, silencer

D) spill valves, silencer

288 / 655

288. When air is known to be present in the hydraulic system you should:

A) expect services to operate faster

B) have the air bled from the system

C) ignore it because normal operation will remove it

D) allow the accumulator to automatically adjust itself

289 / 655

289. A modern aeroplane is equipped with warning lights in the cockpit to monitor the hydraulic system. What does the illumination of the hydraulic oil temperature light indicate?

A) High fluid temperature in the main pressure line

B) Overheated fluid in either the main or the emergency reservoir

C) Overheated hydraulic fluid in one of the pump return lines

D) Mechanical failure of one engine driven pump

290 / 655

290. In the case of a failure of a cut-out valve:

A) a full flow relief valve is fitted down stream of it.

B) the terminal pressure will be controlled by adjusting the pump RPM

C) a full flow relief valve is fitted upstream of it.

D) a full flow relief valve is not required

291 / 655

291. In order to control the rate of movement of a service in a hydraulic system a... valve is used

A) shuttle

B) modulating

C) restrictor

D) debooster

292 / 655

292. One reason for fitting an accumulator in a hydraulic system is to:

A) absorb pressure surges

B) relieve excess pressure

C) provide a reservoir of fluid

D) minimise the possibility of pump cavitation

293 / 655

293. A complex hydraulic system may pressurize the oil reservoir by means of bleed air from the engines, this is:

A) To avoid air from developing in the system

B) In case of oil leakage the air might serve as a backup medium

C) To increase the hydraulic pressure in the system and thereby alter its performance

D) To secure reliable oil supply to the hydraulic pumps

294 / 655

294. A hydraulic restrictor valve:

A) slows down the build up of hydraulic system pressure

B) is used to limit actuator travel

C) reduces hydraulic system pressure when the pressure is too high

D) slows down the rate of movement of the actuators and other hydraulic services

295 / 655

295. The oil reservoir in a hydraulic system has the purpose to serve as:

A) a point at which the fluid can purge itself of air

B) an expansion chamber to provide a space for the fluid when its volume increases due to a high temperature

C) the compartment that stores the fluid

D) all of the above alternatives are correct

296 / 655

296. If it is necessary to refill the hydraulic system and the approved hydraulic fluid is not available, you may:

A) not use any fluid other than the approved type from a clean container

B) drain hydraulic fluid from another aircraft and use it

C) use hydraulic fluid from another aircraft provided that this fluid is filtered first

D) use any hydraulic fluid

297 / 655

297. An accumulator is precharged with nitrogen to a pressure of 500 lb.in-2. The hydraulic system is then pressurised to 1500 lb.in-2. The accumulator gauge will now read:

A) 500 lb.in-2.

B) 2500 lb.in-2

C) 100 lb.in-2

D) 1500 lb.in-2.

298 / 655

298. An ACOV will:

A) extend the life of the accumulator

B) ensure the pump is always on load

C) provide an idling circuit when the accumulator is fully charged

D) provide an idling circuit when a selection is made

299 / 655

299. A floating separator in a hydraulic system is used to:

A) measure the hydraulic reservoir contents

B) separate accumulator air from the emergency air bottle

C) separate gas and fluid in the accumulator

D) separate pressurising air and fluid in the reservoir

300 / 655

300. Red mineral hydraulic fluid (DTD 585) requires:

A) synthetic rubber seals

B) mineral seals

C) fibre seals

D) natural rubber seals

301 / 655

301. A variable displacement type hydraulic pump:

A) Moves a constant flow of fluid

B) Moves fluid quantity dependent on the system demand

C) Delivers almost constant pressure independent on system resistance

D) Moves no fluid when engine runs on idle.

302 / 655

302. The colour of fluid DTD 585 is:

A) Green

B) Purple

C) Blue

D) Red.

303 / 655

303. In hydraulic system, a shuttle valve:

A) is a self-lapping non-return valve

B) allows two possible sources of pressure to operate one unit.

C) allows two units to be operated by one pressure source

D) regulates pump delivery pressure

304 / 655

304. In a hydraulic system, a selector valve is used to:

A) select between normal and emergency systems

B) provide a direct air supply back to the reservoir to pressurise the fluid

C) act as a pressure relief valve

D) raise and lower the undercarriage

305 / 655

305. When there is no flow in the tubes of a hydraulic system, the hydraulic pressure

A) is equal in all the tubes

B) is lower in the longer tubes

C) is lower in the smaller tubes

D) is higher in the smaller tubes

306 / 655

306. Internal leakage in a hydraulic system will cause:

A) fluid loss

B) an increased fluid pressure

C) a decreased fluid temperature

D) an increased fluid temperature

307 / 655

307. In an accumulator of the hydraulic system, a separator

A) reduces the size of the accumulator

B) isolates the gas from the fluid

C) removes the dissolved gases from the fluid

D) maintains the fluid level in the reservoir

308 / 655

308. The Ram Air Turbine (RAT) provides emergency hydraulic power for:

A) nose wheel steering after the aeroplane has landed

B) flight controls in the event of loss of engine driven hydraulic power

C) undercarriage selection and automatic brake system

D) flap extension only

309 / 655

309. In an aircraft hydraulic system, it is permissible to use:

A) only the specified fluid

B) any hydraulic fluid available

C) any fluid with equivalent pressure capacity

D) any fluid of the same specific gravity

310 / 655

310. An automatic cut-out valve is installed in some hydraulic systems to:

A) ensure that the pump is always on load

B) provide an idling circuit when a selection is made

C) extend the life of the accumulator

D) provide an idling circuit when the accumulator is fully loaded

311 / 655

311. Hydraulic reservoirs are pressurised by:

A) ram air in flight only

B) engine bleed air from turbine engine

C) air from the air conditioning system

D) separate helium gas system

312 / 655

312. Should the incorrect hydraulic fluid be used in a system:

A) there will be no effect.

B) any leaks will cause loss of pressure

C) seal damage will result

D) corrosion will be caused in the jacks

313 / 655

313. A hydraulic circuit utilising a constant volume pump would also require

A) an automatic cut-out valve

B) a pressure relief valve.

C) an automatic cut-out valve and an accumulator

D) a hand pump

314 / 655

314. A hydraulic reservoir is installed in a hydraulic system primarily

A) to maintain fluid between a jack and the accumulator

B) to compensate for leaks and expansion, and to serve as a storage tank

C) to provide a volume of fluid to indicate system temperature

D) to allow a space for extra spare fluid to be stored

315 / 655

315. Case drain filters are:

A) designed to allow hydraulic pump lubricating fluid to drain to atmosphere

B) to enable pump lubricating fluid to be used to monitor pump condition

C) fitted to prevent debris from the reservoir reaching the system

D) fitted in the reservoir outlet

316 / 655

316. What is the purpose of a " relief valve" in the hydraulic system?

A) Make sure that the pressure in the system exceeds a certain minimum pressure

B) Make sure that the pressure does not exceed the max. permitted pressure in the system

C) Make sure that the emergency hand pump will produce enough pressure when used

D) To " even out" the pressure in the system

317 / 655

317. To allow for failure of the normal method of system pressure limiting control, a hydraulic system often incorporates:

A) a high pressure relief valve

B) a stand-by hydraulic pump

C) an accumulator

D) auxiliary hydraulic motors

318 / 655

318. The pressure filter in a hydraulic system:

A) is fitted down stream of the pump

B) can be by passed when maximum flow is required

C) filters the fluid returning to the tank

D) clears the fluid as it leaves the reservoir

319 / 655

319. Hydraulic pressure in a closed centre system:

A) varies in direct proportion to system demands

B) is greater in pipes of small diameters

C) is greater in pipes of large diameters

D) increases when a service selection is made

320 / 655

320. Pascal’ s law states that:

A) applied force acts equally in all directions

B) pressure is inversely proportional to load

C) oxygen can be used to charge the accumulators

D) liquid is compressible

321 / 655

321. When excess pressure is relieved by the pressure relief valve it is:

A) vented overboard

B) returned to the reservoir return line

C) returned to the inlet side of the actuator

D) returned to the inlet side of the pump

322 / 655

322. Hand pumps in hydraulic systems are generally

A) single acting

B) rotary

C) hydraulically operated

D) double acting

323 / 655

323. Hydraulic reservoirs are pressurised in order to:

A) maintain a constant fluid level

B) provide a reserve of stored energy

C) prevent over pressurisation

D) minimise the possibility of pump cavitation

324 / 655

324. An automatic cut-out valve will

A) limit pump wear

B) prevent hydraulic lock

C) raise fluid boiling point

D) prevent foaming

325 / 655

325. The arrow on a non-return valve points:

A) away from the smaller connection

B) in the direction of flow

C) towards the larger connection

D) against the direction of flow

326 / 655

326. In addition to energy storage the accumulator of the hydraulic system is used:

A) for fluid storage

B) for pressure storage

C) for dampening pressure surges in the system

D) as a pressure relief valve.

327 / 655

327. If hydraulic system pressure is 3000 psi and the piston strokes of two hydraulic actuators are equal, the work done by a 4 inch sq. actuator compared with the work done by a 1 inch sq. actuator will be:

A) half as much

B) four times higher

C) the same.

D) twice as much

328 / 655

328. A shuttle valve:

A) acts as a non-return valve

B) allows one source to operate two units

C) is used to replace NRVs

D) allows two supply sources to operate one unit

329 / 655

329. Discounting the possibility of leak, the level in a hydraulic reservoir will

A) fluctuate with jack displacement and accumulator pressure

B) always remain the same

C) increase as ambient temperature decreases

D) initially increase with system pressurization

330 / 655

330. A hydraulic lock is said to exist when there is:

A) flow, but no movement

B) a constant return flow to the hydraulic reservoir

C) no flow, jacks are stationary

D) no flow, but the jacks continues to move under gravity or other external forces

331 / 655

331. What type of hydraulic seal will seal in one direction only?

A) square section

B) diamond section

C) 'O' section

D) chevron

332 / 655

332. Cleanliness of the hydraulic fluid during use is assured by:

A) a return filter

B) a contamination detection valve which opens when the fluid is contaminated

C) a pressure filter, a case drain filter and a return filter

D) a pressure filter

333 / 655

333. A hydraulic fuse is used:

A) In the event of a hydraulic leak upstream, to control the leak rate

B) As protection for an electrically operated hydraulic pump

C) In the event of a hydraulic leak down stream, the fuse prevents total fluid loss.

D) To operate a hydraulic pump overheat warning light

334 / 655

334. A milky appearance at the sight glass of a hydraulic reservoir is an indication of:

A) pressure bleeding is occurring

B) air in the system fluid

C) water contamination

D) excessive fluid pressure

335 / 655

335. The fluid level in the reservoir of the system fitted with an accumulator

A) will fail when the system is depressurised

B) will be unaffected by system pressurisation

C) will rise when the system is pressurised

D) will fall when the system is pressurised

336 / 655

336. In a hydraulic system, a thermal relief valve is fitted to:

A) prevent convection currents

B) prevent a leak back of pressure

C) relieve excess pressure

D) prevent excess temperature

337 / 655

337. A hydraulic non-return valve:

A) closes if inlet hydraulic pressure drops well below outlet pressure

B) opens if inlet hydraulic pressure equals outlet hydraulic pressure.

C) can only be fitted if provided with a hydraulic by-pass selector

D) closes if inlet hydraulic pressure exceeds outlet hydraulic pressure

338 / 655

338. With a one way check valve (NRV):

A) flow stops when input pressure is greater than output pressure

B) flow stops when the thermal relief valve offloads the hand pump.

C) flow stops when input pressure is less than output pressure

D) flow starts when input pressure is less than output pressure

339 / 655

339. A HYDRAULIC FUSE will:

A) In case of a too high pressure in the system, open up and relieve the pressure by dumping the fluid overboard or back to the reservoir

B) Activate the actuators after the pilot has used the emergency hand pump

C) Detect a sufficient pressure drop across itself, or a specified volume of fluid passing through itself, and then shut off the flow of fluid to prevent the system of emptying itself

D) Direct the hydraulic fluid to the proper actuator according to the power pack and sequence valve

340 / 655

340. In a hydraulic system utilising a constant delivery pump, essential components are:

A) An accumulator and automatic cut-out valve

B) A relay valve and accumulator

C) An accumulator and shuttle valve

D) A relay valve and jettison valve

341 / 655

341. The purpose of a reservoir is:

A) to allow for fluid displacements, small leaks, thermal expansion and contents monitoring.

B) to provide a housing for the instrument transmitters

C) to provide a housing for the main system pumps and so obviate the need for backing pumps

D) to enable the contents to be checked

342 / 655

342. What is the purpose of a one way restrictor valve?

A) To prevent cavitation in the down line of the undercarriage circuit when the undercarriage is selected up

B) To prevent cavitation in the up line of the undercarriage circuit when the undercarriage is selected down

C) To prevent cavitation in the down line of the undercarriage circuit when the undercarriage is selected down.

D) To prevent cavitation in the up line of the undercarriage circuit when the undercarriage is selected up

343 / 655

343. Different diameter actuators supplied with the same pressure at same rate:

A) exert the same force

B) exert different forces.

C) will move at different speeds

D) will move at the same speed

344 / 655

344. A hand pump will draw its supply from:

A) the bottom of the reservoir

B) the stack pipe.

C) above the normal level

D) through the U tube to prevent siphoning

345 / 655

345. The presence of a film of oil on the ram of a hydraulic jack, or actuator, when checked prior to flight:

A) taking place. D)

B) is to prevent corrosion taking place

C) is an indication of a leaking seal

D) is to prevent ice forming on the ram

346 / 655

346. The tanks of a hydraulic system are pressurized

A) by bleed air coming from the turbine-engine

B) in flight only

C) by an auxiliary system

D) by the air conditioning system

347 / 655

347. The purpose of an accumulator in a hydraulic system is to:

A) remove air from the system.

B) all of the above

C) store fluid under pressure

D) relieve excess pressure

348 / 655

348. In a hydraulic reservoir with a stack pipe fitted, the pipe line to the emergency pump is connected to:

A) the base of the stack pipe

B) the top of the stack pipe

C) the return

D) the bottom of the reservoir

349 / 655

349. Thermal relief valves are set to:

A) the same pressure as the ACOV cut-out pressure

B) the limiting temperature for the hydraulic fluid.

C) a higher pressure than the ACOV cut-out pressure

D) the same pressure as the ACOV cut-in pressure.

350 / 655

350. A pressure maintaining valve:

A) relieves excessive hydraulic system pressure.

B) provides a constant supply of fluid to the EDP inlet.

C) maintains a supply of fluid to secondary services following hydraulic system pressure drop.

D) maintains a supply of fluid to essential services following hydraulic system pressure drop

351 / 655

351. Large transport aeroplane hydraulic systems usually operate with a system pressure of approximately:

A) 3000 psi

B) 4000 psi

C) 2000 psi

D) 1000 psi

352 / 655

352. High frequency vibration and hammering in a hydraulic system is:

A) normal and does not affect the system efficiency

B) caused by filter clogging

C) caused by pipe diameter fluctuations.

D) is detrimental to the system

353 / 655

353. The hydraulic device similar to an electronic diode is a:

A) distribution valve

B) check valve

C) shutoff valve

D) flow control valve

354 / 655

354. Cavitation in a hydraulic pump can be discovered by a loud irregular sound. What might be the reason for a pump to cavitate?

A) There is not enough fluid in the reservoir and the pump picks up too much air

B) Flaps, landing gear and the primary flight controls are operated at the same time

C) The pump has an excessive load

D) The fluid is too hot due to frequent employment of the airplane hydraulically operated controls

355 / 655

355. For an aeroplane hydraulic supply circuit, the correct statement is:

A) the pumps are always electric due to the high pressures which they must deliver (140 to 210 kg/cm2).

B) the regulation system deals only with emergency operation and is not applied to all hydraulic services but only those considered as essential

C) the reservoir constitutes a reserve of hydraulic fluid maintained under pressure by a pneumatic back pressure (air or nitrogen) and destined to serve as a fluid or pressure reserve.

D) the security components comprise the filters, the pressure relief valves, the by-passes, and the fire shut-off valve

356 / 655

356. One of the functions of " automatic cut out valve" in a hydraulic supply system is to:

A) limit pump wear

B) prevent hydraulic lock

C) prevent hydraulic hammering

D) maintain the fluid at a constant viscosity

357 / 655

357. One of the functions of " automatic cut out valve" in a hydraulic supply system is to:

A) prevent hydraulic lock.

B) prevent hydraulic hammering

C) limit pump wear

D) maintain the fluid at a constant viscosity

358 / 655

358. A variable displacement hydraulic pump on start up will always be at:

A) mid stroke

B) maximum stroke

C) minimum stroke

D) a position decided by the fluid temperature

359 / 655

359. Hydraulic accumulators are normally charged to:

A) System pressure

B) Half system pressure

C) 75% of system pressure

D) 1000 psi

360 / 655

360. Hydraulic fluids of synthetic origin are

A) purple

B) red

C) pink

D) blue

361 / 655

361. A constant pressure hydraulic pump is governed by:

A) a control piston

B) engine RPM

C) an automatic cut out

D) a swash plate that senses the fluid temperature

362 / 655

362. Hydraulic pressure of 3000psi is applied to a jack whose area is 2sq in. If the same pressure is applied to a jack of 4sq in:

A) both jacks will move at the same speed

B) both jacks exert the same force

C) the smaller jack will exert a force of 50lb, and the larger a force of 25lb

D) the smaller jack will exert a force of 6000lb, and the larger jack a force of 12000lb

363 / 655

363. A non return valve or check valve:

A) closes if inlet pressure exceeds outlet pressure

B) opens if inlet pressure equals outlet pressure

C) can only be fitted if provided with a by pass selector

D) closes if inlet pressure ceases

364 / 655

364. The type of hydraulic oil used in modern hydraulic systems is:

A) water and glycol

B) mineral oil

C) vegetable oil

D) synthetic oil

365 / 655

365. Emergency air bottle may be used for

A) to compensate for a low fluid level in reservoir

B) an emergency power supply in the event of main system fluid pressure loss

C) an emergency power supply to raise the undercarriage

D) to charge the accumulators in an emergency

366 / 655

366. Restrictor valves are fitted:

A) to slow down the rate of pressure build-up.

B) to limit pump rotation

C) to slow down the operation of a service in one direction

D) to limit jack travel

367 / 655

367. Hydraulic fluids must have the following characteristics:

1. thermal stability

2. low emulsifying characteristics

3. corrosion resistance

4. good resistance to combustion 5. high compressibility

6. high volatility 7. high viscosity

The combination regrouping all the correct statements is:

A) 1, 3, 4, 6

B) 1, 2, 5, 7

C) 1, 2, 3, 4

D) 2, 3, 4, 5

368 / 655

368. The reason for the pressure accumulator in the hydraulic system is:

A) It works as a backup fluid reservoir, which increases the capacity of the system

B) It serves as a water reservoir that collects water from the hydraulic fluid

C) The accumulator compensates for fluid-volume variation due to changes in temperature

D) The accumulator serves as an internal shock absorber for the hydraulic system

369 / 655

369. An airspace is provided above the fluid in a reservoir to:

A) Allow the fluid to boil at attitude

B) Allow for the carriage of extra fluid on a long haul flight

C) Allow for jack ram displacement

D) Provide an emergency reserve of air should the accumulator fail

370 / 655

370. What colour is the hydraulic liquid in a modern jet airliner?

A) Purple

B) Pink

C) Yellow

D) Red

371 / 655

371. Hydraulic pressure of 3000Pa is applied to an actuator, the piston area of which is 0.02m2 and the same pressure is exerted on actuator whose area is 0.04m2

A) both jacks will move at the same speed

B) both have the same force

C) the smaller jack will exert a force of 60N and the larger 120N

D) the smaller jack will exert a force of 600N and the larger 1200N

372 / 655

372. What is the purpose of a flop tube, as fitted to a hydraulic reservoir?

A) to prevent total loss of fluid in the event of leakage in the main supply

B) to compensate for changes in aircraft attitude

C) to pressurize the hydraulic reservoir

D) to compensate for thermal expansion

373 / 655

373. When a hydraulic system is pressurised, the hydraulic quantity in the reservoir:

A) falls

B) remains at the same level

C) rises

D) initially falls then rises

374 / 655

374. Hydraulic fluid should have which of the following properties?

A) High flash point

B) Low flash point

C) High freezing point and low boiling point

D) Freezing point not lower than 0 degrees " C"

375 / 655

375. The hydraulic pressure gauge provides information regarding the pressure of:

A) the hydraulic pressure in the system.

B) the proportional pressure in the system.

C) the air and hydraulic fluid pressure in the system

D) the air in the accumulator

376 / 655

376. The contents of the hydraulic fluid reservoir are checked. They indicate that the reservoir is at the full level. The system is then pressurised. Will the contents level:

A) fall below the " full" mark

B) remain at the same level

C) fall to a position marked 'full accs charged'.

D) rise above the " full" mark

377 / 655

377. For calculation purposes, hydraulic fluid is considered to be:

A) compressible at low temperatures only

B) incompressible

C) compressible at high temperatures only

D) compressible

378 / 655

378. Skydrol 7000 is... A ... in colour, requires a...B... seal and is often used because...C...

A) A green B Teflon C it is cheap and easily produced

B) A straw B Teflon C has better fire retardant properties

C) A yellow B Butyl-rubber C has better fire retardant properties

D) A green B Butyl-rubber C has better fire retardant properties

379 / 655

379. The main reasons for using pressurised hydraulic reservoirs on jet transport aircraft is/are:

A) To assure that an adequate supply of fluid free from foaming always is present at the pump inlet.

B) To maintain a minimum system pressure in case of hydraulic pump failure and enabling the pilot to lower flaps and gear with the help of this reservoir pressure.

C) To compress the hydraulic fluids

D) To increase the output pressure of the system

380 / 655

380. The purpose of a pressure maintaining valve is to:

A) give priority to one system over another

B) maintain system pressure at all times

C) maintain pressure to the hydraulic reservoir

D) ensure essential services operate in an emergency.

381 / 655

381. The colour of hydraulic fluid MIL-H-5606 is:

A) red.

B) green

C) purple

D) blue

382 / 655

382. An accumulator has a gas charge pressure of 800 psi and the aircraft system has a residual hydraulic pressure of 600 psi. The accumulator gas gauge should read:

A) 600 psi

B) 1400 psi

C) 200 psi

D) 800 psi

383 / 655

383. A ... valve is used where two different values of pressure are required in a system

A) Pressure release

B) Restrictor

C) Pressure relief

D) Pressure reducing

384 / 655

384. In a modern hydraulic system, " hydraulic fuses" can be found. Their function is:

A) To isolate a part of the system and protect it against accidental pollution

B) To prevent total system loss in case of a leaking hydraulic line

C) To switch to the secondary system in case of a leak in the primary brake system

D) To allow by-passing of a hydraulic pump in case it is subject to excessive pressure, without further damage to the system

385 / 655

385. A restrictor valve in a hydraulic system:

A) controls the rate of movement of a service

B) controls the rate of build-up of pressure in the system

C) restricts the maximum pressure in the system

D) controls the distance the jack moves

386 / 655

386. A restrictor valve operates to:

A) restrict the number of services available

B) controls the distance an actuator moves

C) controls the rate of pressure build up in the system

D) controls the rate of movement of a service

387 / 655

387. In an enclosed system pressure is felt:

A) more when the piston is moving than when it is stationary

B) the same at both ends between the piston and the cylinder head

C) more at the cylinder end than the piston head

D) more at the piston head than the rest of the cylinder

388 / 655

388. In a hydraulic system the master cylinders inner diameter is 10 mm2, and the actuator cylinders inner diameter is 100 mm2. If you press the master-cylinder 2 cm by using a 100 N force, the actuator cylinder will move: :

A) 2 mm and produce a force of 1000 N

B) 1 mm and produce a force of 500 N

C) 2 mm and produce a force of 100 N

D) 2 cm and produce a force of 100 N

389 / 655

389. An accumulator air charge is 1000 psi. When the hydraulic system is pressurised to 1800 psi, the accumulator gauge will read:

A) 1800 psi

B) 1000 psi

C) 2800 psi

D) 800 psi

390 / 655

390. Prevention of damage to components in the closed part of a hydraulic system due to heat expansion:

A) Is achieved by pressurising the reservoir

B) Is achieved by using a thermal relief valve

C) Is achieved by the use of expansion joints in the pipelines

D) Is achieved by using a pressure release valve

391 / 655

391. In a simple hydraulic system a pressure relief valve is fitted to:

A) The return side of the system

B) The pressure side of the system

C) The vent side of the system

D) The suction side of the system

392 / 655

392. To prevent leakage of a mineral based fluid in two directions which seal is used?

A) a synthetic '0' seal

B) a butyl chevron seal

C) a natural 'U' seal

D) a butyl '0' seal

393 / 655

393. The specification of hydraulic fluids (mineral, vegetable or ester based) is:

A) not generally distinguishable by colour

B) generally distinguishable by colour only if they are from the same manufacturer

C) always distinguishable by taste and smell

D) generally distinguishable by colour

394 / 655

394. When topping up a system with fluid, the correct type can be recognised by:

A) its specific pressure capacity

B) its smell

C) its specific gravity

D) its colour

395 / 655

395. The indication of an internal leak in a hydraulic system will be:

A) excessive system pressure

B) a rise in fluid temperature

C) a rise in reservoir fluid level

D) a fall in reservoir fluid level

396 / 655

396. What is the purpose of a pressure switch in a hydraulic supply system?

A) to operate the pressure gauge

B) to operate a warning light in the event of system pressure failure

C) to switch off the pump when maximum pressure is reached

D) to prevent excess pressure build-up in the system

397 / 655

397. An automatic cut-out valve is used in a:

A) Constant pressure system

B) Fixed volume pressure control system

C) Both of these

D) Neither of these

398 / 655

398. Where in the hydraulic system are the overheat indicators?

A) At the using units

B) At the coolers

C) At the pumps

D) At the reservoirs

399 / 655

399. If hydraulic system pressure is 3000 psi and the piston strokes of two actuators are equal, the pressure on a 4 inch sq. jack compared to the pressure on a 1 inch sq. jack will be:

A) half as much

B) four times as much

C) the same

D) twice as much

400 / 655

400. An Automatic Cut Out Valve is installed in a hydraulic system:

A) to prevent excessive pump temperatures

B) before the electrically driven pump

C) before the engine driven pump

D) to provide an idling circuit when the accumulator is full

401 / 655

401. A hydraulic fluid should possess:

A) A low flash point and should remain free flowing

B) A low viscosity at all ambient temperatures

C) A high viscosity at all ambient temperatures

D) A degree of compressibility with no increase in viscosity at high temperatures

402 / 655

402. In an aircraft hydraulic system it is permitted to use:

A) Any oil that is available

B) Any oil of the same specific gravity

C) Only an oil specified for use in that system.

D) Any oil of the same colour

403 / 655

403. A restrictor valve in a hydraulic system is fitted in the:

A) supply to the undercarriage retraction actuator

B) undercarriage down line and the flap up line.

C) undercarriage up line and the flap down line

D) EDP

404 / 655

404. The purpose of a shuttle valve is to:

A) Protect a hydraulic system from overpressure

B) Relieve excess pressure in hydraulic systems

C) Prevent overloading of the hydraulic pump

D) Supply an operating unit with the most appropriate system pressure

405 / 655

405. The hydraulic hand pump fitted to aircraft is:

A) Generally single acting

B) Rotary acting

C) Generally double acting

D) Used on flaps and landing gear only

406 / 655

406. Where in a hydraulic system might overheat indicators be installed?

A) In the reservoirs

B) At the pumps

C) At actuators

D) At the coolers

407 / 655

407. The aircraft hydraulic system is designed to produce

A) small pressure and small flow

B) high pressure and small flow

C) small pressure and large flow

D) high pressure and large flow

408 / 655

408. Hand pumps are usually fitted to aircraft systems to:

A) Ensure that the gas charge in the accumulator remains at the correct value

B) Provide a ground service facility and for emergency use

C) Maintain the level of fluid in the reservoir

D) Allow the normal operation of in-flight services

409 / 655

409. A hydraulic fuse is fitted in a hydraulic system, to prevent excessive fluid loss in the event of a leak:

A) in the reservoir

B) downstream of the fuse

C) anywhere in the system

D) upstream of the fuse

410 / 655

410. In a closed cylinder filled with fluid, pressure is:

A) higher on the piston than on the cylinder walls.

B) the same in all directions on all surfaces.

C) higher on the cylinder walls than on the piston

D) inversely proportional to cylinder volume

411 / 655

411. In a hydraulic braking system, an accumulator is precharged to 1200 psi. An electrically driven hydraulic pump is started and provides a system pressure of 3000 psi. The hydraulic pressure gauge which is connected to the gas section of the accumulator, reads:

A) 1200 psi

B) 4200 psi

C) 3000 psi

D) 1800 psi

412 / 655

412. The purpose of pressurising some hydraulic reservoirs is to:

A) provide emergency pressure if the pump should fail

B) provide a positive pressure to the return line

C) provide a positive feed to the main pump

D) prevent cavitation at the pressure filter

413 / 655

413. The function of the selector valve is to:

A) communicate system pressure to either side of an actuator

B) automatically activate the hydraulic system

C) select the system to which the hydraulic pump should supply pressure

D) discharge some hydraulic fluid if the system pressure is too high

414 / 655

414. If the system pressure is 3,000 psi the force provided by a 4 square inch jack compared to the force provided by a 2 square inch area jack will be:

A) 3,000 lb in total

B) 6,000 Ib greater.

C) 6,000 lb less

D) the same

415 / 655

415. In a hydraulic system fitted with a constant volume pump, when maximum system pressure is reached:

A) an idling circuit is created via the reservoir

B) the pump off loads completely

C) the pump maintains a small leak rate through the pump, whilst in the off load position

D) the pump is disengaged by a pressure operated clutch

416 / 655

416. When air is found in a hydraulic system:

A) have the air bled from the system

B) expect services to operate faster

C) ignore it, it has no effect

D) allow the accumulator to automatically adjust itself

417 / 655

417. Hydraulic fluids used in systems of modern airliners are:

A) Phosphate ester base fluids

B) Water base fluids.

C) Mineral base fluids

D) Vegetable base fluids.

418 / 655

418. A 100lb force is applied to each of two unconnected actuators. The area of one is 2 inch2 and the area of the other is 4 inch2:

A) The pressure inside the small actuator will be 50 psi and the pressure inside the large one will be 25 psi

B) The pressure inside the small actuator will be 200 psi and the pressure inside the large one will be 400 psi.

C) The pressure inside the both actuators will be 200lbf.

D) The pressure inside the both actuators will be 200psi

419 / 655

419. The hydraulic fluid is changed, but the wrong fluid is replaced. This would lead to:

A) system failure from leaks and blocked filters, high temp and possible corrosion

B) high operating fluid temperature

C) normal operation

D) seal damage and jack corrosion

420 / 655

420. Hydraulic fluids:

A) Are irritating to eyes and skin and cause high fire risk

B) Cause high fire risk.

C) Do not require special care

D) Are irritating to eyes and skin

421 / 655

421. A constant pressure hydraulic pump is controlled by:

A) maintaining engine RPM

B) a control piston which adjusts the swash plate angle

C) an automatic cut-out valve in combination with an accumulator

D) a swash plate that senses fluid temperature

422 / 655

422. A shuttle valve is used for:

A) changeover from main to auxiliary system in the case of failure

B) maintaining fluid pressure when the emergency system fails

C) preventing fluid loss from a leaking jack

D) selecting the direction of fluid flow to a jack (e.g.: flaps in or out.)

423 / 655

423. DTD 585 (MIL-H 5606) is coloured:

A) red.

B) blue.

C) purple.

D) green

424 / 655

424. In a modern airliner what is hydraulic fluid used?

A) Mineral/alcohol

B) Vegetable

C) Synthetic.

D) Mineral

425 / 655

425. If one uses the incorrect fluid in a hydraulic system:

A) corrosion problems could arise in all affected system components

B) the hydraulic system will function properly

C) damage to the seals could result

D) inspection intervals will decrease

426 / 655

426. When a variable volume pump is stationary

A) the stroke does not alter

B) the aircraft engines are unserviceable

C) it is at minimum stroke

D) it is at maximum stroke

427 / 655

427. A pressure maintaining or priority valve:

A) is used to increase pressure in the sys.

B) is used to control pressure to services requiring less than system pressure.

C) enables ground operation of services when the engines are off.

D) is used to ensure available pressure is directed to essential services

428 / 655

428. A circuit utilising a constant volume pump would also require:

A) an automatic cut out

B) a relief valve

C) a hand pump

D) an automatic cut out and accumulator

429 / 655

429. Slow, sluggish operation of a hydraulic system is:

A) low accumulator charge pressure causing rapid system pressure fluctuations

B) an indication of air in the system and it requires bleeding

C) caused by a blocked high pressure filter element

D) an indication of water in the hydraulic system

430 / 655

430. Hydraulic fluid is considered to be:

A) compressible

B) compressible inside it's rated operating temperature range only

C) incompressible.

D) compressible at high temperatures only

431 / 655

431. The control surface that rotates the aircraft about its longitudinal axis is/are the:

A) Rudder

B) Flaps.

C) Elevator

D) Ailerons

432 / 655

432. If an artificial feel unit is fitted, it would be connected:

A) in series with the primary controls

B) to the secondary flight controls

C) in parallel with the primary controls

D) close to the control column

433 / 655

433. Trailing edge flaps:

A) Increase lift at a lower AOA

B) Reduce lift at a lower AOA

C) Increase lift at a higher AOA

D) Reduce lift at a higher AOA

434 / 655

434. With which system is differential control associated?

A) Elevator system

B) Rudder system

C) Aileron system

D) Trim system

435 / 655

435. The purpose of the fairleads in a cable control system is to:

A) to guide the cables on to the pulley wheels

B) alter the angle of deflection of the cables

C) to keep the cable straight and clear of structure

D) to attach the cables to chain drives

436 / 655

436. "Feel" units are fitted when

A) Spring tabs are fitted to the control system

B) Powered controls are fitted to the aircraft

C) Servo tabs are fitted to the aircraft

D) Power assisted controls are fitted to the aircraft

437 / 655

437. A servo tab moves?

A) According to he airflow that surrounds it.

B) Parallel to the control surface to which it is hinged

C) Opposite of the control surface to which it is hinged

D) In the same direction of the control surface to which it's hinged

438 / 655

438. Control surface flutter is minimised by:

A) changing the wings before they reach their critical life.

B) aerodynamic balance of the control cables

C) reducing the moment of the critical engine

D) mass balance of the control surfaces

439 / 655

439. In a steep turn to the left, when using spoilers...

A) The right aileron will ascend, the left one will descend, the right spoiler will extend and the left one will retract

B) The right aileron will ascend, the left one will descend, the right spoiler will retract and the left one will extend

C) The right aileron will descend, the left one will ascend, the right spoiler will retract and the left one will extend.

D) The right aileron will descend, the left one will ascend, the right spoiler will extend and the left one will retract

440 / 655

440. On an aeroplane, spoilers are:

A) upper wing surface devices, their deflection is symmetrical or asymmetrical

B) lower wing surface devices, their deflection is symmetrical or asymmetrical

C) upper wing surface devices, their deflection is always asymmetrical.

D) lower wing surface devices, their deflection is always asymmetrical

441 / 655

441. If the control stick of an aircraft is moved forward to the right, the left aileron will move:

A) Up, and the elevator will move up

B) Down, and the elevator will move down

C) Down, and the elevator will move up.

D) Up, and the elevator will move down.

442 / 655

442. If the control stick of an aircraft with properly rigged flight controls is moved rearward and to the left, the right aileron will move:

A) down and the elevator will move up.

B) down and the elevator will move down

C) up and the elevator will move up

D) up and the elevator will move down

443 / 655

443. If the control stick of an aircraft with properly rigged flight controls is moved rearward and to the left, the right aileron will move:

A) down and the elevator will move up

B) up and the elevator will move up.

C) up and the elevator will move down

D) down and the elevator will move down

444 / 655

444. An artificial feel unit is necessary in the pitch channel when:

A) there is a trimmable stabilizer.

B) the elevators are actuated by irreversible servo-control units

C) the elevators are fitted with servo-tabs or trim tabs

D) the elevators are actuated by reversible servo-control units

445 / 655

445. A Kruger flap is:

A) To give the aircraft better short field performance

B) An anti balanced type of flap with the purpose of making the controls smoother

C) A trailing edge flap which is operating automatically.

D) A leading edge flap type which is formed by extending an area of the wing downwards and forward at the leading edge.

446 / 655

446. The trim tab:

A) increases hinge moment and reduces control surface efficiency

B) reduces hinge moment and increases control surface efficiency

C) increases hinge moment and control surface efficiency

D) reduces hinge moment and control surface efficiency

447 / 655

447. The purpose of pulley wheels in cable control systems is:

A) to prevent the cable from slackening.

B) to ensure smooth operation of the system

C) The purpose of pulley wheels in cable control systems is:

D) to ensure the cable tensions are equal throughout the system

448 / 655

448. To yaw the aircraft to the right

A) the right rudder pedal is pushed forward and the rudder moves to the right.

B) the left rudder pedal is pushed forward and the rudder moves to the left

C) the left rudder pedal is pushed forward and the rudder moves to the left.

D) the right rudder pedal is pushed forward and the rudder moves to the left.

449 / 655

449. An artificial feel unit system:

A) is necessary on a reversible servodyne unit.

B) must be mounted in parallel on an irreversible servo-control unit

C) is mounted in parallel on a spring tab

D) must be mounted in series on an irreversible servo-control unit

450 / 655

450. The elevators of a conventional airline are used to provide rotation about the:

A) Lateral axis.

B) Directional axis

C) Longitudinal axis.

D) Vertical axis

451 / 655

451. If an artificial feel unit is fitted, it would be connected:

A) in series with the primary controls

B) in parallel with the primary controls.

C) in parallel with the secondary controls

D) in series with the secondary controls

452 / 655

452. A Yaw Damper is:

A) An elevator augmenter to avoid the nose-down effect at speeds greater than M=0.8

B) An elevator augmenter

C) A rudder damper designed to avoid the " Dutch roll" .

D) A roll trim tab.

453 / 655

453. The advantages of fly-by-wire control are:

Reduction of the electric and hydraulic power required to operate the control surfaces
2. Lesser sensitivity to lightning strike
3. Direct and indirect weight saving through simplification of systems
4. Immunity to different interfering signals
5. Improvement of piloting quality throughout the flight envelope
The combination regrouping all the correct statements is:

A) 1 and 5

B) 2 and 3

C) 1 and 2

D) 3 and 5

454 / 655

454. How do differential ailerons work?

A) equalise the drag on up going and down going wings

B) increase drag on up going wing and decrease drag on down going wing

C) Increase lift on down going wing and decrease lift on up going wing

D) equalise the lift on up going and down going wings.

455 / 655

455. What is the name of the control surface that rotates an aeroplane about its longitudinal or roll axis?

A) The elevator.

B) The trim tabs

C) The ailerons

D) The rudder

456 / 655

456. One type of flap used on aircraft moves down and increases the wing area by moving aft when lowered. This flap is known as:

A) Slotted flap

B) Fowler flap

C) Fowler flap

D) Split flap

457 / 655

457. On an airplane, the Krueger flaps are:

A) leading edge flaps close to the wing tip

B) leading edge flaps close to the wing root

C) trailing edge flaps close to the wing root

D) trailing edge flaps close to the wing tip

458 / 655

458. The purpose of a trim tab (device) is to:

A) trim the aeroplane at low airspeed.

B) reduce or to cancel control forces

C) lower manoeuvring control forces

D) trim the aeroplane during normal flight

459 / 655

459. Control surface flutter:

A) provides additional lift for take-off and landing in the event of engine failure

B) is a means of predicting the critical safe life of the wing

C) occurs at high angles of attack

D) is a destructive vibration that must be damped out within the flight envelope

460 / 655

460. The reason for the trim switch on a control column to consist of two separate switches is:

A) To reduce the probability of a trim-runaway

B) To be able to use two different trim speeds, slow trim rate at high speed and high trim rate at low speed

C) To prevent that both pilots perform opposite trim inputs

D) Because there are two trim motors

461 / 655

461. What are " Kruger" flaps?

A) Cowling flaps

B) Aileron trim tabs

C) Trailing edge flaps.

D) Leading edge flaps

462 / 655

462. Which of the following helps to prevent flutter?

A) Inset Hinges

B) Mass Balance

C) Horn Balance

D) Balance Tabs

463 / 655

463. A q feel unit is:

A) used to give the pilot some control feedback at varying altitudes by sensing static pressure changes.

B) also known as an Artificial feel Unit

C) used to give the pilot some feedback of flap position by sensing the dynamic pressure.

D) used to give the pilot some control feedback dependent on the rate of acceleration

464 / 655

464. Some aircraft uses a fly by wire system to move the primary flight controls, this system is based on:

A) Hydraulic power only

B) Mechanical power transmitted by steel wires

C) Secondary controls such as speed brakes

D) Electrical signals from a computer sent to hydraulic actuators

465 / 655

465. On an aircraft, the Kruger flap is a:

A) leading edge flap close to the wing tip.

B) leading edge flap

C) trailing edge flap

D) leading edge flap close to the wing root

466 / 655

466. During the landing run, when wheel brake anti-skid units are activated

A) brake fluid pressure is reduced by returning fluid to the reservoir via the brake control valve.

B) brake fluid pressure is reduced by returning fluid from the brake unit direct to return

C) full brake pressure is applied to the brake units

D) brake fluid pressure is reduced by returning fluid from the brake unit direct to the accumulator

467 / 655

467. Control on the ground for small aeroplanes is provided by steering the nose wheel through connections to the rudder pedals, but large aeroplanes have normally:

A) electrical power steering

B) hydraulic power steering

C) pneumatic power steering

D) mechanical power steering.

468 / 655

468. On the brake assembly there is an anti-skid system. From which device does the anti-skid control box get the information to regulate the brake pressure?

A) From a hydraulic pressure sensor

B) From the pitot static system

C) From a wheel speed sensor

D) From the airspeed indicator, corrected to ground speed.

469 / 655

469. Oil is used in an oleo strut to:

A) Support the weight of the aircraft.

B) Limit the speed of extension and compression of the strut

C) Limit the speed of compression of the strut

D) Lubricate the piston within the cylinder

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470. A red band painted on the wall of a tyre is a:

A) light spot

B) creep mark

C) heavy spot

D) balance mark.

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471. The ABS (Auto Brake System) is being disconnected after landing

A) at a certain low speed

B) by pilot action

C) automatically

D) the system is always armed

472 / 655

472. What is an essential requirement in a Nose Wheel Steering System?

A) A follow-up mechanism

B) Triplicate servo operation

C) Feedback

D) An emergency air back up

473 / 655

473. In a commercial transport aircraft the landing gear operating system is usually

A) Mechanically driven.

B) Pneumatically driven

C) Hydraulically driven

D) Electrically driven

474 / 655

474. The pressure needed to operate the wheel brakes on a large aircraft comes from:

A) a self contained power pack

B) the hydraulic reservoir

C) the aircraft main hydraulic system

D) the pilots brake pedals

475 / 655

475. The type of brake unit found on most transport aeroplanes is a:

A) Single disk brake

B) Multiple disk brake

C) Drum type brake

D) Belt brake

476 / 655

476. The most likely cause of brake fade is:

A) worn stators

B) the pilot reducing the brake pressure

C) oil or grease on the brake drums

D) overheating

477 / 655

477. At an aircraft taxiing speed of l0 mph the antiskid braking system is:

A) operative only on the main wheel brakes

B) inoperative

C) operative only on the nosewheel brakes

D) operative.

478 / 655

478. A main landing gear is said to be LOCKED DOWN when:

A) the actuating cylinder is at the end of its travel

B) the strut is locked by an overcenter mechanism

C) the corresponding indicator lamp is amber

D) it is in the down position

479 / 655

479. If the gas pressure is too high in an oleo leg it will:

A) The leg extension will be lower than normal

B) Cause the leg extension to be more than normal

C) Not affect the functioning as a pressure relief valve will ensure pressure is brought within limits

D) The leg extension will not change.

480 / 655

480. Oil is required in an oleo strut to:

A) limit the speed of extension and compression of the strut

B) lubricate the piston within the cylinder

C) support the weight of the aircraft.

D) limit the speed at which the strut compresses

481 / 655

481. The movement of the gear on lowering is normally damped to:

A) Prevent the fluid becoming aerated

B) Prevent the hydraulic fluid becoming overheated

C) Make the lowering time greater than the raising time.

D) Counteract the force of gravity which would bring the gear down too fast

482 / 655

482. A scissor is a component found on landing gears. Its function is to:

A) prevent any rotation of the oleo strut in the undercarriage shock absorber.

B) make the body gears pivot when the nosewheel is turned through more than 20°

C) transform the translational movement of the rudder pedals into the rotational movement of the nosewheel

D) create the wheel pitch on bogie gears

483 / 655

483. The disk brakes have more or less replaced the drum brakes. Why?

A) Because disk brakes weighted less and lasted longer

B) Because disk brakes allow an antiskid action

C) Owing to a loss of braking action due to heat generation problem

D) Because disk brakes allow a greater dissipation kinetic energy.

484 / 655

484. If the oleo-pneumatic shock strut extension of a landing gear on the ground is designed to be 6 inches, but it is found to be 2 inches:

A) the nitrogen (or air) pressure is insufficient

B) the hydraulic fluid pressure is more than required

C) the hydraulic fluid pressure is insufficient

D) the nitrogen (or air) pressure is more than required

485 / 655

485. Gear retraction systems are classified according to the power source used for retraction and extension. Which are the most frequently used on larger aircraft?

A) Electrical and pneumatic

B) Hydraulic

C) Electrical and hydraulic

D) Mechanical.

486 / 655

486. An accumulator may be fitted in a brake system to:

A) Provide an emergency reserve of pressure in the event of main system pressure failure

B) Prevent thermal expansion from being transmitted from the main system

C) Compensate for fluid loss when the brakes are applied

D) Modulate the response when the brakes are initially applied

487 / 655

487. The most probable cause of main wheel shimmy is:

A) excessive shock absorber extension.

B) shock absorber extension low

C) worn torque links or toggles

D) low tyre inflation pressure

488 / 655

488. Multi Disc brake units are assessed for wear

A) by wear indicator pins which extend as brake wear takes place.

B) by measuring individual brake pad thickness

C) by wear indicators that change colour as brake wear takes place.

D) by wear indicator pins that retract into the torque plate as brake wear occurs.

489 / 655

489. The tyre pressures are checked after a long taxi to the ramp following landing. The pressures will have:

A) risen by 10% of their original value

B) fallen by 15% from their rated value

C) remained constant.

D) risen by 15% from their rated value

490 / 655

490. When the main undercarriage gear is selected 'DOWN' in flight, it is locked down by:

A) sequence valves

B) spring loaded jacks imposing a geometric lock on the side stays or drag struts

C) Hydraulic down locks

D) locking pins with warning flags.

491 / 655

491. What is reducing the shocks on the landing gear on an oleo shock absorber?

A) The oil that is forced through a metering orifice

B) Springs inside the strut.

C) Compression of the oil.

D) Cushion of compressed air

492 / 655

492. In a hydraulic braking system, the accumulator is:

A) an accumulator designed to restore brake energy in the event of a hydraulic failure

B) designed to take up the hydraulic energy filtered by the anti-skid system in order to prevent wheel blocking.

C) a buffer accumulator whose function is to assist the hydraulic system during high intensity braking

D) a damping type accumulator designed to take up the pressure fluctuations of the automatic braking system.

493 / 655

493. Shimmy occurs on the nosewheel landing gear during taxiing when:
1. the wheels tend to describe a sinusoidal motion on the ground
2. the wheels no longer respond to the pilot's actions
This effect is overcome by means of:
3. the torque link
4. an accumulator associated with the steering cylinder
The combination of correct statements is:

A) 1, 3

B) 1, 4

C) 2, 3

D) 2, 4

494 / 655

494. The nose wheel assembly must be centred before retraction because