2A651 Cdc Volume 3

Front 1

What is the composition of JP–8 fuel?
a. Gasoline and kerosene.
b. Gasoline and diesel fuel.
c. Diesel fuel and kerosene.
d. Diesel fuel and aviation gasoline.

Back 1

a. Gasoline and kerosene.

Front 2

At room temperature, how many times longer will it take water to settle out of JP–8 than out
of gasoline?
a. Two.
b. Three.
c. Four.
d. Five.

Back 2

c. Four.

Front 3

Jet aircraft operating at moderately high altitudes increase the fuel system’s susceptibility to
an icing condition, further aggravated by the
a. lower viscosity of jet fuels.
b. higher viscosity of jet fuels.
c. lower viscosity of free water.
d. higher viscosity of free water.

Back 3

b. higher viscosity of jet fuels.

Front 4

The main fuel control allows the jet engine to safely accelerate, reducing the possibility of
a. flameout.
b. turbine seizure.
c. compressor shift.
d. overtemperature.

Back 4

a. flameout.

Front 5

The purpose of a fuel/oil cooler in a fuel system is to
a. heat the fuel and cool the oil.
b. cool the fuel and cool the oil.
c. heat the fuel and heat the oil.
d. cool the fuel and heat the oil.

Back 5

a. heat the fuel and cool the oil.

Front 6

During a visual inspection, how can you tell when a fuel filter is clogged?
a. A green flag pops out of the filter.
b. Fuel pressure from the fuel pump is low.
c. A differential pressure indicator is actuated.
d. There is no way to tell without disassembling the filter.

Back 6

c. A differential pressure indicator is actuated.

Front 7

On a dual-spool, axial-flow engine, what controls thrust production of the engine?
a. Regulating engine RPM.
b. Regulating compressor discharge pressure.
c. Controlling turbine exhaust pressure.
d. Controlling turbine inlet temperature.

Back 7

d. Controlling turbine inlet temperature.

Front 8

During jet engine deceleration, a hydromechanical fuel control schedules fuel flow as a
function of
a. RPM.
b. inlet temperature.
c. burner pressure.
d. inlet pressure.

Back 8

c. burner pressure.

Front 9

What type of fuel control uses items such as thermocouples, relays, amplifiers, and solenoids
to help control a jet engine?
a. Pneumatic.
b. Fuel injection.
c. Hydromechanical.
d. Electrohydromechanical.

Back 9

d. Electrohydromechanical.

Front 10

Which term describes a jet engine fuel metering device that is really two fuel controls in one
component?
a. Unified.
b. Combined.
c. Bimechanical.
d. Electrosecondary.

Back 10

a. Unified.

Front 11

Calibration and/or adjustment screws that require setting during an engine trim procedure
must be
a. replaced.
b. die marked.
c. safety sealed and/or lockwired.
d. applied a thread locking compound.

Back 11

c. safety sealed and/or lockwired.

Front 12

When in the primary mode, what controls the operation of the F100-PW–220 engine?
a. MEC.
b. PMG.
c. TSFC.
d. DEEC.

Back 12

d. DEEC.

Front 13

On an F100-PW–220 engine, the DEEC is cooled by
a. oil.
b. fuel.
c. ram air.
d. hydraulic fluid.

Back 13

b. fuel

Front 14

On an F100-PW–220 engine, how many modes is the MFC capable of operating in?
a. One.
b. Two.
c. Three.
d. Four.

Back 14

b. Two.

Front 15

Which F100-PW–220 engine fuel system component controls pressurization of the core
engine fuel system?
a. Fuel nozzle.
b. P&D valve.
c. N2 sensor.
d. Tt 2.5 sensor.

Back 15

b. P&D valve.

Front 16

Which stage of compressor air drives the augmenter fuel pump on an F100-PW–220
engine?
a. 7th.
b. 10th.
c. 13th.
d. 14th.

Back 16

c. 13th.

Front 17

Core engine fuel flow sequence on an F100-PW–220 engine starts at the main fuel pump
and then goes through the
a. AFP, AFC, fuel/oil cooler, P&D, and fuel nozzles.
b. MFC, fuel/oil cooler, P&D, and fuel nozzles.
c. AFC, AFP, fuel/oil cooler, P&D, and fuel nozzles.
d. fuel/oil cooler, P&D, MFC, and fuel nozzles.

Back 17

b. MFC, fuel/oil cooler, P&D, and fuel nozzles.

Front 18

On the T56 engine, how many and what type of fuel pumps are contained in the fuel pump
and filter assembly?
a. 3 gear; 1 boost.
b. 2 gear; 2 boost.
c. 2 gear; 1 boost.
d. 1 gear; 2 boost.

Back 18

c. 2 gear; 1 boost.

Front 19

On a T56 engine, what controls the rotary movement of the fuel control metering valve?
a. Temperature.
b. Engine speed.
c. Throttle position.
d. Compressor inlet pressure.

Back 19

d. Compressor inlet pressure.

Front 20

Which T56 engine component receives 120 percent of the engine fuel requirement?
a. TD valve.
b. Fuel control.
c. TD control.
d. Fuel nozzle.

Back 20

a. TD valve.

Front 21

In addition to the visual inspection, what other type of inspection does the T–56 engine fuel
nozzle require?
a. Nondestructive.
b. Spray pattern.
c. Pre-torque.
d. Ultrasonic.

Back 21

b. Spray pattern.

Front 22

In what position must the TD valve switches be placed in order to make the T56 engine fuel
trimming system inoperative?
a. OFF.
b. NULL.
c. AUTO.
d. LOCKED.

Back 22

b. NULL.

Front 23

On the T56 engine, what compares the desired throttle setting from the coordinator with the
actual *** signal from the thermocouples?
a. TD valve.
b. Speed-sensitive control.
c. TD potentiometers.
d. TD amplifier.

Back 23

d. TD amplifier.

Front 24

Which T56 engine component sends the fuel to the fuel manifold?
a. TD valve.
b. Main fuel pump.
c. TD amplifier.
d. Fuel control.

Back 24

a. TD valve.

Front 25

On the T56 engine, the manifold pressure switch opens to deenergize the fuel enrichment
relay when fuel pressure, in psi, in the manifold reaches
a. 30 psi.
b. 40 psi.
c. 50 psi.
d. 60 psi.

Back 25

c. 50 psi.

Front 26

When the null orifice on the T56 engine TD valve is set at zero, how much fuel will the
valve bypass?
a. 0%.
b. 10%.
c. 20%.
d. 30%.

Back 26

c. 20%.

Front 27

The temperature datum system static check must be made whenever which component has
been replaced?
a. Compressor.
b. Power section.
c. Torquemeter shaft.
d. Reduction gearbox.

Back 27

b. Power section.

Front 28

When classified as to structure, which of the following is not a type of an oil pump?
a. Gear.
b. Gerotor.
c. Rotogear.
d. Sliding vane.

Back 28

c. Rotogear.

Front 29

Which type of oil pump consists of a gear and rotor within a housing?
a. Gear.
b. Gerotor.
c. Rotogear.
d. Sliding vane.

Back 29

b. Gerotor.

Front 30

Chip detectors have an electrical connection for making which type of check?
a. AC high-voltage.
b. DC high-voltage.
c. Continuity.
d. Polarity.

Back 30

c. Continuity.

Front 31

Which type of oil cooler operates on the same principle as a radiator in an automobile?
a. Air.
b. Fuel.
c. Hydraulic.
d. Pneumatic.

Back 31

a. Air.

Front 32

What type of oil seal has soft metal as its basic composition and allows a small amount of
airflow to prevent oil seepage?
a. Silicone.
b. Carbon.
c. Synthetic.
d. Labyrinth.

Back 32

d. Labyrinth.

Front 33

Use extreme care when working with labyrinth seals because of their
a. soft metal construction; these seals can be damaged easily.
b. soft metal construction; they are sharp and can cut your hand.
c. hard metal construction; they are sharp and can cut your hand.
d. hard metal construction; these seals can damage the bearing races.

Back 33

a. soft metal construction; these seals can be damaged easily.

Front 34

When an engine is not operating, static preload for a carbon oil seal is provided by
a. air pressure.
b. oil pressure.
c. spring pressure.
d. hydraulic pressure.

Back 34

c. spring pressure.

Front 35

The F100-PW–100 engine oil pressure varies with rear compressor rotor speeds (N2),
engine inlet oil temperature, and
a. oil jet pressure.
b. fan turbine speed.
c. oil nozzle condition.
d. number of oil jets used.

Back 35

c. oil nozzle condition.

Front 36

In an engine oil tank, which device separates the air from the oil?
a. Aerator.
b. Deaerator.
c. Check valve.
d. Bypass valve.

Back 36

b. Deaerator.

Front 37

Which type of oil system stores the oil in a tank fitted to the side of the engine?
a. Dry sump.
b. Wet sump.
c. Cold tank.
d. Hot tank.

Back 37

a. Dry sump.

Front 38

Which type of oil system design places the oil cooler in the pressure subsystem?
a. Cold tank.
b. Wet tank.
c. Dry tank.
d. Hot tank.

Back 38

d. Hot tank.

Front 39

On an F100 engine, the breather pressurizing valve is internally mounted in the
a. oil tank.
b. gearbox.
c. oil filter.
d. oil pump.

Back 39

b. gearbox.

Front 40

If the red button on an F100-PW–220 engine oil filter pops out and remains extended, the
a. button is defective.
b. scheduled oil change is due.
c. design ambient pressure has been exceeded.
d. design pressure differential has been exceeded.

Back 40

d. design pressure differential has been exceeded.

Front 41

On an F100-PW–220 engine, the air/oil coolers are mounted on the fan duct and use
a. secondary fan airflow as a coolant.
b. secondary fan airflow as an oil heater.
c. primary core engine airflow as a coolant.
d. primary core engine airflow as an oil heater.

Back 41

a. secondary fan airflow as a coolant.

Front 42

On an F100-PW–220 engine, what component permits oil to bypass the oil filter during cold
weather starts?
a. Oil relief valve.
b. Filter poppet valve.
c. Oil pressure transmitter tap.
d. Filter assembly bypass valve.

Back 42

d. Filter assembly bypass valve.

Front 43

The AE2100D3 oil tank pendulum is designed to supply pressurized oil for approximately
how long during negative G conditions?
a. Minimum of 10 seconds.
b. Minimum of 20 seconds.
c. Maximum of 10 seconds.
d. Maximum of 20 seconds.

Back 43

a. Minimum of 10 seconds.

Front 44

Approximately how many GPM does the AE2100D3 PUAD lube and scavenge pump
provide at engine PTO?
a. 3.
b. 5.
c. 7.
d. 9.

Back 44

b. 5.

Front 45

What AE2100D3 component drives the PGB lube and scavenge pump?
a. Alternator stator.
b. Prop gearbox.
c. PUAD.
d. GMAD.

Back 45

d. GMAD.

Front 46

The ACAWS message low oil level advisory for the AE2100D3 engine occurs when the
engine oil level drops below
a. 2 US gallons.
b. 3 US gallons.
c. 4 US gallons.
d. 5 US gallons.

Back 46

c. 4 US gallons.

Front 47

The hazardous property of modern jet engine oil the journeyman must be aware of is
a. toxicity.
b. viscosity.
c. alkalinity.
d. corrosiveness.

Back 47

d. corrosiveness.

Front 48

The primary benefit of identifying an impending failure through the OAP is
a. improved safety.
b. increased component life.
c. reduced maintenance cost.
d. increased equipment availability.

Back 48

a. improved safety.

Front 49

Who is responsible for ensuring that the OAP operates properly?
a. Project monitor.
b. Logistics commander.
c. Propulsion flight chief.
d. Laboratory supervisor.

Back 49

a. Project monitor.

Front 50

What are microscopic metallic particles in the oil system called?
a. Wear metals.
b. Friction metals.
c. Precious metals.
d. Transformation metals.

Back 50

a. Wear metals.

Front 51

Before taking an oil sample from a drain, drain enough fluid into a container in order to
a. check for large particles.
b. check the drain operation.
c. drain off uncirculated oil.
d. drain off water and sludge.

Back 51

d. drain off water and sludge.

Front 52

Under what condition would you not receive an OAP laboratory sample report?
a. The sample is the first taken after an oil change.
b. The aircraft is on TDY.
c. It was a special oil sample.
d. The results are normal.

Back 52

d. The results are normal.

Front 53

The SEM/EDX analysis process differs from conventional oil analysis in that the
SEM/EDX
a. samples must be sent off-site for analysis.
b. particles must be oil free for analysis to take place.
c. samples can only be obtained in an intermediate maintenance shop.
d. provides results only concerning equipment and components condition.

Back 53

b. particles must be oil free for analysis to take place.

Front 54

What is the term for the process of producing voltage in a conductor when it passes through
a magnetic field?
a. Static.
b. Electronics.
c. Mutual induction.
d. Electromagnetic induction.

Back 54

d. Electromagnetic induction.

Front 55

On a simple AC generator, which item takes the current from the slip rings to operate the
electrical device?
a. Brushes.
b. Commutator.
c. Rotating loop.
d. Permanent magnet.

Back 55

a. Brushes.

Front 56

Which part of a generator acts as an automatic switching device, changing alternating
current to direct current?
a. Brushes.
b. Slip rings.
c. Commutator.
d. Permanent magnet.

Back 56

c. Commutator.

Front 57

What provides the PTO shaft that is used to drive the CSD?
a. Engine fittings.
b. Engine adapter.
c. Aircraft fittings.
d. Aircraft adapter.

Back 57

b. Engine adapter.

Front 58

The slide-type resistor in the EGT circuit is used to
a. adjust the thermocouples.
b. calibrate the EGT indicator in the flight station.
c. compensate for minor voltage buildups in the circuit.
d. compensate for differences in temperatures at altitude.

Back 58

b. calibrate the EGT indicator in the flight station.

Front 59

What is the primary input power to the main ignition system?
a. 28 VAC.
b. 28 VDC.
c. 120 VAC.
d. 120 VDC.

Back 59

b. 28 VDC.

Front 60

Which unit of an AC ignition system develops 20,000 volts?
a. Inverter.
b. Capacitor.
c. Generator.
d. Transformer.

Back 60

d. Transformer.

Front 61

On early ignition systems, the high-energy capacitor-type ignition system does not include a
a. centrifugal switch.
b. gas-filled rectifier.
c. capacitor.
d. vibrator.

Back 61

a. centrifugal switch.

Front 62

On early ignition systems, what is the purpose of compositors in an ignition system?
a. Prevent the points from arcing.
b. Cause a voltage to jump across the spark gap in the ignition unit.
c. Step up voltage high enough to break down the air gap of the igniter plug.
d. Hold back the current flow until the voltage is high enough to be rectified.

Back 62

c. Step up voltage high enough to break down the air gap of the igniter plug.

Front 63

The T56 engine speed-sensitive control, measured in RPM, lets electrical current flow to the
fuel and ignition system at
a. 16% RPM.
b. 30% RPM.
c. 65% RPM.
d. 94% RPM.

Back 63

a. 16% RPM.

Front 64

On the T56 engine, at what percent of engine RPM is the ignition system turned off?
a. 16%.
b. 30%.
c. 65%.
d. 94%.

Back 64

c. 65%.

Front 65

How many independent circuits are within an F100-PW–100 engine ignition system?
a. One.
b. Two.
c. Three.
d. Five.

Back 65

c. Three.

Front 66

From where does the AE2100D3 ignition system receive its electrical power?
a. Generator.
b. Aircraft battery.
c. Essential DC bus.
d. Engine-mounted alternator stator.

Back 66

d. Engine-mounted alternator stator.

Front 67

What is the output VAC of the AE2100D3 alternator stator?
a. 1 to 20 VAC.
b. 20 to 40 VAC.
c. 40 to 60 VAC.
d. 60 to 80 VAC.

Back 67

b. 20 to 40 VAC.

Front 68

What component monitors the AE2100D3 ignition exciters spark rate?
a. FADEC.
b. GMAD.
c. PUAD.
d. NIU.

Back 68

d. NIU.

Front 69

How many sparks per second can the AE2100D3 ignition exciters produce?
a. 1 to 3.
b. 2 to 5.
c. 3 to 6.
d. 4 to 7.

Back 69

d. 4 to 7.

Front 70

The two air source requirements for a pneumatic starter to operate properly are sufficient
a. volume and velocity.
b. volume and pressure.
c. temperature and velocity.
d. temperature and pressure.

Back 70

b. volume and pressure.

Front 71

The OSG on the cartridge-pneumatic starter consists of a body containing
a. a shaft and piston.
b. an igniter and cable.
c. two pinned flyweights and a piston.
d. two pinned flyweights and an igniter.

Back 71

c. two pinned flyweights and a piston.

Front 72

Which item initially rotates the JFS?
a. ESS PTO.
b. Electric motor mounted on the aircraft.
c. Hydraulic motor.
d. Engine PTO.

Back 72

c. Hydraulic motor.

Front 73

Which type of combustion chamber does the JFS use?
a. Can.
b. Annular.
c. Can-annular.
d. Restricted flow.

Back 73

b. Annular.

Front 74

What engine section houses the JFS combustion section?
a. Geartrain.
b. Turbine plenum.
c. Generator control unit.
d. Gas generator and accessory drive assembly.

Back 74

b. Turbine plenum.

Front 75

Which item on the JFS provides pads for mounting the fuel atomizer assembly?
a. Stator ring.
b. Turbine plenum.
c. Exhaust housing.
d. Generator assembly.

Back 75

b. Turbine plenum.

Front 76

On the F–15 secondary power system CGB, how are the isolation decouplers extended?
a. Manually.
b. Electrically.
c. Hydraulically.
d. By spring pressure.

Back 76

c. Hydraulically.

Front 77

Oil is supplied to the F–15 JFS through the
a. oil tank.
b. aircraft filter.
c. JFS oil system.
d. CGB oil system.

Back 77

d. CGB oil system.

Front 78

Discharge air used for aircraft engine anti-icing to heat-critical areas is taken from which
engine area?
a. Compressor.
b. Combustion.
c. Augmentor.
d. Turbine.

Back 78

a. Compressor.

Front 79

On an F108 engine, which manifold is anti-ice air ducted from?
a. Pneumatic.
b. Augmentor.
c. Combustion case.
d. Compressor case.

Back 79

a. Pneumatic.

Front 80

On an F108-CF–100 engine anti-ice system, what is the purpose of the air injector on the air
regulator?
a. Provide controlled airflow during VBV operation.
b. Control air velocity at high RPM.
c. Provide auxiliary airflow during engine start.
d. Control air temperature and pressure.

Back 80

d. Control air temperature and pressure.

Front 81

On an F110-GE–129 engine, the anti-icing system prevents detrimental formation and
accumulation of ice on front frame struts, forward centerbody, and
a. ring cowl.
b. fan inlet guide vane flaps.
c. variable exhaust nozzle flaps.
d. C-D duct.

Back 81

b. fan inlet guide vane flaps.

Front 82

On an F110-GE–129 engine, compressor bleed air is used for anti-icing, customer bleed,
and
a. VSV actuator control.
b. IGV actuator control.
c. low-pressure turbine cooling functions.
d. main engine fuel pump operation.

Back 82

c. low-pressure turbine cooling functions.

Front 83

What law does the C-D supersonic inlet use to slow down the airflow?
a. Ohm’s law.
b. Bernoulli’s law.
c. Newton’s first law.
d. Newton’s third law.

Back 83

b. Bernoulli’s law.

Front 84

The compressor bleed system reduces the probability of compressor stall in a dual-rotor
engine by
a. reducing the amount of air available to the N2 compressor.
b. reducing the amount of air available to the N1 compressor.
c. increasing the amount of air delivered to the N2 compressor.
d. increasing the amount of air delivered by the N1 compressor.

Back 84

a. reducing the amount of air available to the N2 compressor.

Front 85

Once the cooling airflow has done its job of cooling the turbine section, where does it go?
a. Through a heat exchanger.
b. Out the turbine case bleed holes.
c. Into the gas stream to exit the engine.
d. Back to the compressor to be used again.

Back 85

c. Into the gas stream to exit the engine.

Front 86

On an F108-CF–100 engine, the variable bleed valves bleed air from the
a. N1 compressor.
b. N2 compressor.
c. first stage fan.
d. last stage of compression.

Back 86

a. N1 compressor.

Front 87

On an F108-CF–100 engine, the direction of the variable bleed valve rotation is controlled
by the
a. flexible shafts.
b. feedback cable.
c. fuel gear motor.
d. ballscrew actuators.

Back 87

c. fuel gear motor.

Front 88

On an F110-GE–129 engine, which component supplies fuel pressure to operate the IGV
actuator?
a. Main fuel pump.
b. Main engine control.
c. Augmentor engine control.
d. Digital electronic engine control.

Back 88

b. Main engine control.

Front 89

An F110-GE–129 engine contains how many stages of VSV?
a. Two.
b. Three.
c. Five.
d. Seven.

Back 89

b. Three.

Front 90

What is the purpose of jet engine thrust reversers?
a. Direct engine thrust in a rearward direction.
b. Direct engine thrust upward during landing.
c. Direct engine thrust in the opposite direction.
d. Provide directional control of the aircraft on the ground.

Back 90

c. Direct engine thrust in the opposite direction.

Front 91

On the F117-PW–100 engine, what component controls hydraulic power for actuating both
the fan and core thrust reversers?
a. Electronic engine control.
b. Hydraulic pump.
c. Control valve.
d. Fuel control.

Back 91

c. Control valve.

Front 92

The F117-PW–100 fan thrust reverser door upper right and left sensors send a signal to
which channel or channels of the EEC?
a. A channel.
b. B channel.
c. Both A & B channels.
d. Both A & C channels.

Back 92

a. A channel.

Front 93

The core reverser lock proximity sensors are mounted on the
a. control valve.
b. fwd fan duct.
c. aft fan duct.
d. actuator.

Back 93

d. actuator.

Front 94

How many linear hydraulic actuators are used to deploy and stow the fan thrust on the
F117-PW–100 engine?
a. 2.
b. 3.
c. 4.
d. 5.

Back 94

c. 4.

Front 95

What is the basic function of an augmentor (afterburner) when it is not operating?
a. Act as the basic engine tailpipe.
b. Control engine discharge pressure.
c. Aid in control of engine oil pressure.
d. Help to control pressure and N2 speed.

Back 95

a. Act as the basic engine tailpipe.

Front 96

What is used to open and close flap-type and iris-type variable-exhaust nozzle systems?
a. Oil pressure for both types.
b. Air pressure for both types.
c. Oil pressure for the flap-type and fuel pressure for the iris-type.
d. Fuel pressure for the flap-type and air pressure for the iris-type.

Back 96

b. Air pressure for both types.

Front 97

What component heats augmentor fuel to provide better vaporization and combustion?
a. Fuel control.
b. Fuel spraybars.
c. Fuel manifolds.
d. Fuel/oil cooler.

Back 97

d. Fuel/oil cooler.

Front 98

What are the two main types of augmentor (afterburner) ignition systems?
a. Torch igniter and hot streak.
b. Hot streak and fuel injection.
c. Pilot burner ring and hot streak.
d. Torch igniter and pilot burner ring.

Back 98

d. Torch igniter and pilot burner ring.

Front 99

The F100 engine augmentor’s primary nozzle actuator is driven by cables from the
a. T5 amplifier.
b. unified control.
c. afterburner fuel control.
d. convergent exhaust nozzle control.

Back 99

d. convergent exhaust nozzle control.

Front 100

The F100 engine augmentor’s exhaust nozzle is variable to control engine
a. N2 compressor rotor speed.
b. thrust and fan stall margin.
c. fan stall margin only.
d. thrust only.

Back 100

b. thrust and fan stall margin.