1The thrust of a jet engine is directly proportional to the
- Ratio between N1 and N2
- Velocity of the exhaust gases
- Acceleration of the mass of air
2The compressor shaft rotates on
- Sintered bearings
- Ball and roller bearings
- Plain bearings
3In a pure jet engine, the rate of pressure rise is greatest at the
- Compressor stage
- Combustion stage
- Turbine stage
4A DC started motor disconnects due to
- A centrifugal switch that acts like an overspeed relay
- Current incresing switching off an overspeed relay
- Current decresing switching off an overspeed relay
5For aircrat design purposes, output of a turbo-shaft engine is measured in
- Thrust horsepower
- Shaft horsepower
- Shaft RPM
6A direct drive turboprop engine
- Uses a reduction gearbox to reduce RPM of the propeller
- Uses a single turbine engine
- Has a direct drive to the propeller
7If a helicopter rotor /engine RPM gauge shows split reading, the likely cause is
- Freewheel unit is seized
- The clutch is slipping
- A tail rotor drive failure
8The centrifugal type compressor produces a compression ratio
- Lower than the axial flow compressor
- The same as the axial flow compressor
- Higher than the axial flow compressor
9A free turbine aircraft engine is most likely to be used on a
- High bypass engine
- A helicopter engine
- A direct coupled engine
10A free turbine turbo-prop engine has
- 3 turbine stages driving one shaft
- 2 turbine stages driving one shaft
- 2 or more turbine stages driving two shaft
11A full flow oil system
- A variable oil pressure dependant upon throttle setting
- A hot and cold oil pressure limit
- A single fixed minimum oil pressure
12A directive drive turbo-prop engine
- Has a direct drive to the propeller
- Uses a reduction gearbox to reduce the RPM of the propeller
- Uses a single turbine only
13A gas tubine's propulsion force is produced by
- Reacton of the rearward moving gasses
- Induced airflow into the engine
- Impingement of the gasses on the surrounding air
14A modular constructed gas turbine engine means that
- Its major assemblies can be removed and replaced
- The engine is constructed by the vertical assembly technique
- All engines have a specific component layout
15A twin spool engine has
- One turbine on one shaft
- Two turbines on one shaft
- Two turbines on two shafts
16Advantage of flow type fuel system over pressure type fuel system is
- Has no need for fly weights and governors
- It can take into account rpm, pressure (ambient) and e.g.t.
- It has lower pressure so greater reliability
17An aircraft flying at 800mph would typically use a
- Turbojet
- Turbofan
- Turboprop
18An annular combustion chamber consists of
- A series of flame tubes in an air annulus
- An outer skin and an inner and outer flame skin
- An air tube and a flame tube
19During normal running conditions
- Combustion is self supporting
- Combustion is contiuously supported by ignition
- Combustion is intermittently supported by ignition
20Engines having two independent moving systems are
- Compound engines
- Twin spool engines
- Complex engines
21Gas turbines work on the
- Brayton cycle
- Otto cycle
- Diesel cycle
22How are the combustion chambers cooled
- By fan pressure air
- By HP compressor air
- By LP compressor air
23How is fuel flow varied in a variable displacement pressure type pump
- Direct cable to camplate
- Remote servo pressure
- Alter the camplate angle
24In a ducted fan engine, the fan is driven by the
- Turbine
- Accessory gearbox
- Air passing over the compressor
25In a flow type fuel system, fuel shutoff is done by
- FCU torque motor
- LP fuel cock
- Mechanical ball valve
26In a gas turbine engine, the mass airflow is
- The mass of airflow through the engine multiplied by the velocity of the airflow
- The total mass of airflow through the engine
- The weight of the airflow through the engine multiplied by the tempreature coefficient
27In a pure jet engine the rate of pressure rise is greatest at the
- Turbine stage
- Compressor stage
- Combustion stage
28In a single spool gas turbine engine thr compressor rev/min is
- Equal to the turbine speed
- More than the turbine speed
- Less than the turbine speed
29In a turbine engine used to drive a propeller, the power from the engine is
- The majority of power is used to drive the prop, with the residual giving a jet reaction
- The power is diveded equally
- Majority for jet reaction and the residual to drive the prop
30In a twin spool engine
- The HP turbine drives both LP and HP compressors
- The HP turbine drives the LP compressor and the LP turbine drives the HP compressor
- The LP turbine drives the LP compressor and the HP turbine drives the HP compressor
31In the HEIU, the discharge resistors
- Allows the capacitors to discharge when the unit is switched off
- Allows sufficient voltage to be stored to provide relight facilities up to 55,000 ft
- Protects the units from excessive voltages
32Normal gas turbine engine starting sequence is
- Starter, ignition, fuel
- Starter, fuel, ignition
- Fuell, starter, ignition
33Oil systems consists of
- 4 sub-systems
- 3 sub-systems
- 2 sub-systems
34On a gas turbine engine, what is the fan driven by
- HP turbine
- LP turbine
- IP turbine
35On a twinrotor fan engine, the high pressure turbine drives
- The N1 gas generator
- The high pressure compressor and accessory gearbox
- The fan
36On a twin spool engine, the HP compressor is driven by
- Later stages of the turbine
- Early stages of the turbine
- RAM air over the compressor
37One stage of a turbine is
- NGV then turbine blade
- Turbine blade then NVG
- IGV then turbine blade
38Operation of an engine at a fixed RPM at takeoff (sea-level) causes
- Low thrust when low tempreature is present
- Low thrust when high humidity is present
- Excess thrust when tempreature is high
39Piston engines work on the
- Otto cycle
- Diesel cycle
- Brayton cycle
40Power is adjusted in a gas turbine engine by
- Increasing fuel flow
- Increasing air and fuel flow
- Increasing airflow to the combustion chamber
41Power is adjusted in a variable pitch turboprop aircraft by
- Increasing RPM
- Increasing fuel flow
- Increasing pitch
42Propelling nozzle provide
- Pressure and velocity thrust
- Pressure thrust
- Velocity thrust
43Reverse thrust can only be selected when the throttle is
- 75% power position
- Open
- At the idle stop
44Swirl vanes at the inlet of a combustion chamber
- Stabilize the flame
- Increase gas pressure
- Increase the velocity of the gas
45The annulus of an axial compressor case is
- Convergent
- Parallel
- Divergent
46The basic gas turbine engine cycle is
- Induction, compression, combustion, expansion, exhaust
- Compression, combustion, induction, expansion, exhaust
- Induction, compression, expansion, combustion, exhaustThe bleed valve on a engine at start up
47The bleed valve on a engine at a start up is
48The centrifugal compressor produces a compression ratio
- Lower than the axial flow compressor
- The same as the axial flow compressor
- Higher than th axial flow compressor
49The cycle of a gas turbine engine is
- Completed intwo revolution of the engine
- Completed in one revolution of engine
- Continuous
50The energy remaining in the exhaust or a turbo-shaft engine is
- 2% of the total energy produced
- 50% of the total energy produced
- 20-25% of the total energy produced
51The fan on a turbofan engine is turned by
- Induction of the air across the fan into the compressor
- The combustion chamber gases
- The turbine section
52The fuel flow transmitter is downstrem of
53The gas tubine cycle is a
- Constant volume cycle
- Constant tempreature cycle
- Constant pressure cycle
54The high bypass duct
- Improves propulsive efficiency
- Drives a cabin air compressor
- Provides engine cooling
55The HP compressor is powered by
- The first set of turbines
- The last set of turbines
- The intermediate compressor
56The inlet of a turbo fan is
- Convergent - Divergent
- Convergent
- Divergent
57The largest pressure change in air passing through an engine occurs in the
- Compressor of a turbojet engine
- Propelling nozzle of a turboshaft engine
- Turbine of a turboprop engine
58The majority of power in a free turbine engine is used to
- Expel gases through the exhaust
- Drive the free turbine
- Drive the gas generator
59The majority of the output power from a turbofan is in the form of
- Torque
- Neither thrust nor torque
- Thrust
60The purpose of a high bypass ducted fan engine is to
- Improve thrust
- Improve efficiency
- Reduce size
61The purpose of the LP fuel pump is to
- Pump fuel from the aircraft fuel tanks to the engine
- Ensure the fuel flow govenor gets enough fuel
- Ensure the HP fuel pump does not cavitate
62Thrust is generated in a turboprop system by
- Moving a large mass of air quickly
- Moving a small mass of air quickly
- Moving a large mass of air slowly
63Thrust of a jet turbine engine is directly proportional to the
- Velocity of the exhaust gases
- Acceleration of the mass of air
- Ration between N1 and N2
64Turboprop shaft bearings are
- Plain
- Sintered
- Roller or pin
65What does a 'stage' consist of
- Rotor and stator
- Stator
- Rotor
66What drives the high pressure compressor
- Nearest turbine
- All turbines combined
- Furthest away turbine
67What is an engine stage
- One compressor rotor and one nozzle guide vane
- One rotor plus one stator
- One IGV and one rotor
68What is the pressure increase over one stage of a centrifugal compressor
69What is unit of measurement of EGT
70What percentage of air passing through combustion section is burned
71When the air iss blocked in the HP compressor
- EPR and TGT both decrease
- EPR and TGT both remain the same
- EPR decreases and TGT increases
72Which of these statements is true regarding the Brayton cycle
- Pressure energy is added to the working medium at compression
- Heat energy is added to the working medium at combustion
- Both of the other answere are correct