2A656 Aircraft Electrical And Environmental Systems Journeyman Volume 3

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  • 1/72 Questions

    The constant speed drive (CSD) that is used to drive a 60/80 kilovolts amperes (kVA) generator has an output of approximately

    • 4,000 revolutions per minute
    • 6,000 rpm
    • 8,000 rpm
    • 10,000 rpm
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About This Quiz

This quiz assesses knowledge in Aircraft Electrical and Environmental Systems, focusing on components like the constant speed drive, load controllers, and generator control units in AC power systems. It is designed for 2A656 Journeyman level training, enhancing both practical skills and theoretical understanding.

2A656 Aircraft Electrical And Environmental Systems Journeyman Volume 3 - Quiz

Quiz Preview

  • 2. 

    After you release the stick grip trim selector switch, the trim indicator light

    • Extinguishes

    • Remains illuminated

    • Flashes on and off briefly

    • Remains on throughout the full cycle of the ailerons

    Correct Answer
    A. Extinguishes
    Explanation
    After releasing the stick grip trim selector switch, the trim indicator light extinguishes. This indicates that the trim adjustment has been completed and the aircraft's control surfaces are now properly trimmed.

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  • 3. 

    Remote terminals in the data bus are designed to

    • Turn off inoperative systems

    • Give wind and speed crosswind data

    • Tell the pilot how much fuel is left in the main tank

    • Transfer data between aircraft system and the data bus controller (DBC)

    Correct Answer
    A. Transfer data between aircraft system and the data bus controller (DBC)
    Explanation
    Remote terminals in the data bus are designed to transfer data between the aircraft system and the data bus controller (DBC). The data bus is a communication network that allows different systems within the aircraft to exchange information. Remote terminals act as intermediaries between the individual systems and the data bus controller, facilitating the transfer of data. This enables efficient communication and coordination between various aircraft systems, ensuring smooth operation and functionality.

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  • 4. 

    If you are troubleshooting the landing gear system and replace a bad indicator, your final step is to

    • Take meter readings

    • Limit the malfuction

    • Define the descrepancy

    • Perform operational check of the system

    Correct Answer
    A. Perform operational check of the system
    Explanation
    After replacing a bad indicator in the landing gear system, the final step is to perform an operational check of the system. This is necessary to ensure that the replacement was successful and that the landing gear system is functioning properly. It allows for any potential malfunctions or discrepancies to be identified and addressed before the aircraft is put back into operation. Taking meter readings, limiting the malfunction, and defining the discrepancy may be steps that are taken earlier in the troubleshooting process, but the operational check is the final step to verify the system's functionality.

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  • 5. 

    At what volts alternating current (VAC) range does the generator control unit  in an AC power supply system maintain generator output?

    • 135 [+/-3] VAC

    • 125 [+/-3] VAC

    • 115 [+/-2] VAC

    • 105 [+/-2] VAC

    Correct Answer
    A. 115 [+/-2] VAC
    Explanation
    The generator control unit in an AC power supply system maintains the generator output at a voltage range of 115 VAC with a tolerance of +/- 2 VAC. This means that the generator control unit ensures that the generator output remains within the range of 113 VAC to 117 VAC. This specific voltage range is important for the proper functioning of the AC power supply system and to ensure that the electrical devices connected to it receive the appropriate voltage for their operation.

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  • 6. 

    During which troubleshooting step do you review the Air Force Technical Order (AFTO) form 781A?

    • Learn normal system operation

    • Define the descrepancy

    • Limit the malfunction

    • Take meter readings

    Correct Answer
    A. Define the descrepancy
    Explanation
    The Air Force Technical Order (AFTO) form 781A is reviewed during the troubleshooting step of defining the discrepancy. This form provides detailed information about the specific problem or issue that needs to be addressed. By reviewing the AFTO form 781A, technicians can gain a better understanding of the discrepancy and gather necessary information to effectively troubleshoot and resolve the issue.

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  • 7. 

    The three positions for the speedbrake switch are

    • Open, hold, and land

    • Open, hold, and retract

    • Open, release, and retract

    • Actuate, hold, and retract

    Correct Answer
    A. Open, hold, and retract
    Explanation
    The correct answer is open, hold, and retract. The speedbrake switch has three positions that control the movement of the speedbrake. When the switch is in the open position, the speedbrake is fully extended. In the hold position, the speedbrake remains in its current position. And in the retract position, the speedbrake returns to its stowed position. These three positions allow the pilot to control the deployment and retraction of the speedbrake during different phases of flight.

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  • 8. 

    After replacing the 43 degree position switch on the spreedbrake system, your next and final step is to

    • Ohms check the switch

    • Voltage check the switch

    • Perform an operational check

    • Turn in all tools and test equipment

    Correct Answer
    A. Perform an operational check
    Explanation
    After replacing the 43 degree position switch on the speedbrake system, the next and final step is to perform an operational check. This is necessary to ensure that the newly replaced switch is functioning correctly and is properly integrated into the speedbrake system. By performing an operational check, any potential issues or malfunctions can be identified and addressed before the system is put back into regular use. This step is crucial in maintaining the safety and efficiency of the speedbrake system.

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  • 9. 

    In a continuous loop fire detector system, the shield of the continuous loop is constructed of

    • Soft iron

    • Aluminum

    • Malleable tin

    • INCONEL

    Correct Answer
    A. INCONEL
    Explanation
    INCONEL is the correct answer because it is a high-performance alloy that is commonly used in fire detector systems. It has excellent resistance to high temperatures, corrosion, and oxidation, making it suitable for withstanding the harsh conditions in a continuous loop fire detector system. Soft iron, aluminum, and malleable tin do not possess the same level of durability and resistance, making them less suitable for constructing the shield of the continuous loop.

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  • 10. 

    The data bus component that coordinates the flow of information on the data bus is the

    • Data bus controller

    • Parallel data bus

    • Remote terminal

    • Serial data bus

    Correct Answer
    A. Data bus controller
    Explanation
    The data bus controller is the component that manages the flow of information on the data bus. It controls the timing and synchronization of data transfers between different devices connected to the bus. It ensures that data is transferred accurately and efficiently, coordinating the communication between the sender and receiver devices. The data bus controller plays a crucial role in maintaining the integrity and reliability of data transmission on the data bus.

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  • 11. 

    Placing the landing gear control handle in the up position provides 28 VDC from the 

    • Emergency DC bus

    • Right main DC bus

    • Essential DC bus

    • Isolated DC bus

    Correct Answer
    A. Essential DC bus
    Explanation
    Placing the landing gear control handle in the up position provides 28 VDC from the essential DC bus. This means that when the landing gear control handle is raised, the essential DC bus supplies the necessary power to operate the landing gear system. The essential DC bus is a critical power source in the aircraft, providing power to essential systems even in emergency situations. Therefore, when the landing gear handle is in the up position, the essential DC bus is the correct power source for the landing gear system.

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  • 12. 

    The transformer rectifier units in a volts direct current (VDC) power system convert thee-phase 115 volts alternating current (VAC) into

    • 10 to 12 VDC

    • 26 to 31 VDC

    • 32 to 36 VDC

    • 52 to 56 VDC

    Correct Answer
    A. 26 to 31 VDC
    Explanation
    The transformer rectifier units in a VDC power system convert three-phase 115 VAC into 26 to 31 VDC.

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  • 13. 

    Before operating the aileron trim system, you must supply power to

    • Both the electrical and hydraulic systems

    • The electrical system

    • The hydraulic system

    • The bleed air system

    Correct Answer
    A. Both the electrical and hydraulic systems
    Explanation
    Before operating the aileron trim system, you must supply power to both the electrical and hydraulic systems. This is because the aileron trim system requires electrical power to operate the controls and hydraulic power to move the ailerons. Without power in both systems, the aileron trim system will not function properly.

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  • 14. 

    The VAC power requirement for operation of an AC ignition system is

    • 115 VAC, 60 hertz

    • 208 VAC, 60 hertz

    • 115 VAC, 400 hertz

    • 208 VAC, 400 hertz

    Correct Answer
    A. 115 VAC, 400 hertz
    Explanation
    The correct answer is 115 VAC, 400 hertz. This means that the AC ignition system requires an input voltage of 115 volts and a frequency of 400 hertz in order to operate properly. The voltage and frequency specifications are important for ensuring the system functions correctly and efficiently.

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  • 15. 

    For nose landing gear (NLG) weight on wheels relay C to energize, the aircraft has to be 

    • In the air

    • In the air with gear fully retract

    • In the air with gear down and locked

    • On the ground with weight on the wheels

    Correct Answer
    A. On the ground with weight on the wheels
    Explanation
    The correct answer is "on the ground with weight on the wheels." This is because the NLG weight on wheels relay C is responsible for detecting if the aircraft is on the ground with weight on its wheels. When this condition is met, the relay is energized, indicating that the NLG is in contact with the ground. This information is crucial for various aircraft systems, such as anti-skid braking and landing gear indication.

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  • 16. 

    Which relay or relays must be energized before the anti-collision light will come on?

    • Flasher

    • Anti-collision

    • Both anti-collision and flasher

    • Both anti-collision and landing lights

    Correct Answer
    A. Both anti-collision and flasher
    Explanation
    Before the anti-collision light can come on, both the anti-collision relay and the flasher relay must be energized. The anti-collision relay controls the power supply to the anti-collision light, while the flasher relay controls the flashing function of the light. Therefore, both relays need to be activated in order for the anti-collision light to operate correctly.

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  • 17. 

    What component in the nose wheel steering system provided a quick disconnect capability for turning the nose wheel beyond the steerable range?

    • Scissors assembly

    • Steer control valve

    • Hydraulic linear actuator

    • NWS A/R DISC MSL step switch

    Correct Answer
    A. Scissors assembly
    Explanation
    The scissors assembly in the nose wheel steering system provides a quick disconnect capability for turning the nose wheel beyond the steerable range. This component allows for easy disengagement and re-engagement of the steering system, enabling the nose wheel to be turned further when necessary.

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  • 18. 

    Prior to removing any connector plugs in the nose wheel steering system, you must

    • Review the technical order (TO)

    • Disconnect the power

    • Analyze the malfuction

    • Check for continuity

    Correct Answer
    A. Disconnect the power
    Explanation
    Before removing any connector plugs in the nose wheel steering system, it is necessary to disconnect the power. This is important to ensure safety and prevent any electrical hazards. Disconnecting the power will eliminate the risk of accidental activation of the system while working on it, reducing the chances of injury or damage. It also allows for a controlled environment to analyze any malfunctions or check for continuity in the system. Therefore, disconnecting the power is a crucial step in the process.

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  • 19. 

    Which aircraft interior lights help to reduce the blinding effect of lighting flashes?

    • Flood lights

    • Instument

    • Warning

    • Utility

    Correct Answer
    A. Flood lights
    Explanation
    Flood lights help to reduce the blinding effect of lighting flashes in aircraft interiors. Flood lights are designed to provide a wide and even distribution of light, which helps to minimize the contrast between the bright flashes of lightning and the surrounding cabin environment. This reduces the discomfort and potential temporary blindness that passengers and crew may experience during a lightning strike. Flood lights also ensure that the cabin remains adequately illuminated during the duration of the lightning event, allowing occupants to move around safely.

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  • 20. 

    What happens if the pilot uses the ramp and cargo door switch while the aircraft is in flight?

    • Ramp opens first

    • Door opens first

    • Ramp and door open at the same time

    • The door will open, but the ramp will remain closed

    Correct Answer
    A. Ramp and door open at the same time
    Explanation
    If the pilot uses the ramp and cargo door switch while the aircraft is in flight, the ramp and door will open at the same time. This means that both the ramp and the cargo door will open simultaneously, allowing for the loading or unloading of cargo while the aircraft is still in the air.

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  • 21. 

    The slotted wing flaps are used on heavy aircraft and

    • Extended forward and downward

    • Form a slot between the flap of the wing

    • Increase the chamber or curvature of the wing

    • Lowers the trailing edge to about 40 degrees below its retracted (UP) position

    Correct Answer
    A. Form a slot between the flap of the wing
    Explanation
    The slotted wing flaps are used on heavy aircraft to increase the chamber or curvature of the wing. By extending forward and downward, they form a slot between the flap of the wing. This slot helps to improve the lift characteristics of the wing by allowing air to flow smoothly over the top surface of the wing, reducing turbulence and increasing lift. The slot also lowers the trailing edge of the wing to about 40 degrees below its retracted (UP) position, further enhancing the lift generation capability of the wing.

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  • 22. 

    How does the auxiliary fuel tank indicating system give a no-flow indication?

    • Steady red light

    • Flashing red light

    • Stead amber light

    • Flashing amber light

    Correct Answer
    A. Flashing amber light
    Explanation
    The auxiliary fuel tank indicating system gives a no-flow indication through a flashing amber light. This indicates that there is a problem with the flow of fuel in the auxiliary tank. The flashing light is used to draw attention and signal an issue that needs to be addressed. It serves as a warning to the pilot or operator that there may be a blockage or malfunction in the fuel system, and further investigation or action is required to resolve the issue.

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  • 23. 

    In an AC power supply system, which component controls load division during parallel generator operation?

    • Load controller

    • Underspeed switch

    • Constant speed drive

    • Generator control unit

    Correct Answer
    A. Load controller
    Explanation
    The load controller is the component that controls load division during parallel generator operation in an AC power supply system. It ensures that the load is evenly distributed among the generators to prevent overloading or underloading. By monitoring the load demand and adjusting the output of each generator, the load controller helps maintain a balanced and stable power supply.

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  • 24. 

    If the normal battery will not charge but the standby battery is OK, then you start taking meter readings at the

    • No. 1 transformer rectifier (TR)

    • No. 2 TR

    • Standby battery relay

    • Normal battery relay

    Correct Answer
    A. Normal battery relay
    Explanation
    If the normal battery will not charge but the standby battery is OK, the problem is likely with the normal battery relay. The normal battery relay is responsible for controlling the charging of the normal battery. If it is faulty or not functioning properly, it would prevent the normal battery from charging even if the standby battery is working fine. Therefore, taking meter readings at the normal battery relay would help identify any issues with it and potentially resolve the charging problem.

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  • 25. 

    When a wheel stops rotating, a DC voltage is supplied to the Mark II aintiskid system valve driver by the 

    • Locked wheel circuit

    • Brake indicator driver

    • Touch don protection

    • Pressure bias modulation

    Correct Answer
    A. Locked wheel circuit
    Explanation
    The correct answer is "locked wheel circuit". When a wheel stops rotating, it indicates that the wheel is locked. In such a situation, the locked wheel circuit supplies a DC voltage to the Mark II antiskid system valve driver. This voltage is used to control the valve and release the brake pressure on the locked wheel, preventing skidding and improving vehicle control.

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  • 26. 

    Which component is used as an emergency means of controlling the aileron trim control circuit?

    • Control stick grip trim switch

    • Aileron trim control switch

    • Trim selector switch

    • Auxiliary trim switch

    Correct Answer
    A. Auxiliary trim switch
    Explanation
    The auxiliary trim switch is used as an emergency means of controlling the aileron trim control circuit. This switch is typically located in a convenient location for the pilot to quickly access and operate in case of an emergency or failure of the primary trim control switches. It allows the pilot to manually adjust the aileron trim to maintain proper control and balance of the aircraft.

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  • 27. 

    When a pneumatic starter reaches maximum speed, the ground circuit to the starter relay is opened by

    • The pilot valve

    • A pressure switch

    • Centrifugal switch

    • The on-off switch in the cock-pit

    Correct Answer
    A. Centrifugal switch
    Explanation
    The centrifugal switch is responsible for opening the ground circuit to the starter relay when a pneumatic starter reaches maximum speed. This switch is designed to activate at a specific rotational speed, allowing it to disconnect the starter relay and prevent further power supply to the starter. This mechanism ensures that the starter does not continue running at high speeds, which could lead to damage or malfunction.

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  • 28. 

    How many pulses per min does the strobe light power supply provide the trigger voltage to the strobe anti-collision light?

    • 40 to 50

    • 50 to 60

    • 60 to 70

    • 70 to 80

    Correct Answer
    A. 50 to 60
    Explanation
    The strobe light power supply provides a trigger voltage to the strobe anti-collision light at a rate of 50 to 60 pulses per minute.

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  • 29. 

    The position switch provides voltage to the locked solenoid of the ramp up-lock control valve in the ramp and cargo door system when the

    • Door is in the fully up position

    • Ramp is in the fully up position

    • Door is in the fully down position

    • Ramp is in the fully down position

    Correct Answer
    A. Ramp is in the fully up position
    Explanation
    The position switch is designed to activate the locked solenoid of the ramp up-lock control valve only when the ramp is in the fully up position. This means that when the ramp reaches its maximum raised position, the position switch will send a voltage signal to the locked solenoid, allowing it to lock the ramp in place. This ensures that the ramp remains securely in the fully up position during operation.

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  • 30. 

    What external power system component disconnects external power from the aircraft?

    • Bus protection panel (BPP)

    • Auxiliary power unit (APU)

    • APU/External power contactor (AEPC)

    • APU/external power disconnect contactor (AEDC)

    Correct Answer
    A. APU/external power disconnect contactor (AEDC)
    Explanation
    The APU/external power disconnect contactor (AEDC) is the external power system component that disconnects external power from the aircraft.

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  • 31. 

    What is the last thing you must do before completing a troubleshooting cycle?

    • Repair the defective item

    • Bench check any new parts

    • Perform an operational check

    • Replace any malfunction part

    Correct Answer
    A. Perform an operational check
    Explanation
    Before completing a troubleshooting cycle, it is essential to perform an operational check. This step ensures that the repaired or replaced item is functioning correctly and meets the required specifications. By conducting an operational check, any potential issues or malfunctions can be identified and resolved before considering the troubleshooting process complete. This final step helps to validate the effectiveness of the troubleshooting efforts and ensures that the problem has been successfully resolved.

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  • 32. 

    What type of fuel system valves link to the left wing and aft body tanks to the right wing, mid body, and forward body tanks?

    • Crossfeed

    • Fire shutoff

    • Interconnect

    • Fuel-level control

    Correct Answer
    A. Interconnect
    Explanation
    The correct answer is interconnect. Interconnect valves are fuel system valves that link the left wing and aft body tanks to the right wing, mid body, and forward body tanks. These valves allow fuel to flow between the different tanks, ensuring a balanced distribution of fuel throughout the aircraft. This is important for maintaining stability and performance during flight.

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  • 33. 

    The output of gallons per min (GPM) of the scavenge pumps is approximately

    • 1/2 gpm

    • 1 gpm

    • 2 gpm

    • 3 gpm

    Correct Answer
    A. 2 gpm
    Explanation
    The output of gallons per min (GPM) of the scavenge pumps is approximately 2 gpm. This means that the scavenge pumps are capable of pumping out approximately 2 gallons of fluid per minute.

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  • 34. 

    Frequently used in fire warning systems, the fire detector that has a high-nickel steel rod located along the center line of a stainless steel tube assembly is called

    • A photoconductive cell

    • An iron fireman switch

    • A FENWAL switch

    • A continuous cable

    Correct Answer
    A. An iron fireman switch
    Explanation
    An iron fireman switch is frequently used in fire warning systems. It consists of a high-nickel steel rod located along the center line of a stainless steel tube assembly. This switch is designed to detect fire and trigger the necessary actions to control it. It is a reliable and effective component in fire detection systems.

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  • 35. 

    Momentarily depressing the horn silence switch for the landing gear warning circuit applies

    • Power for the horn silence relay

    • A ground for the horn silence relay

    • A lock-out circuit for the horn silence relay

    • An open circuit for the horn silence switch

    Correct Answer
    A. A ground for the horn silence relay
    Explanation
    When the horn silence switch for the landing gear warning circuit is momentarily depressed, it provides a ground for the horn silence relay. This means that it completes the electrical circuit and allows current to flow through the relay, activating it. The ground connection is necessary for the relay to function properly and silence the horn.

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  • 36. 

    How many boost pumps are there in main fuel tank number 1?

    • Two

    • Three

    • Four

    • Five

    Correct Answer
    A. Four
    Explanation
    There are four boost pumps in main fuel tank number 1.

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  • 37. 

    What component in the landing gear system initiate a signal that identifies the landing gear position and any given time?

    • Limit switches

    • Touchdown relays

    • Control handle solenoids

    • Up-lock and down-lock cylinder sending units

    Correct Answer
    A. Limit switches
    Explanation
    Limit switches are components in the landing gear system that initiate a signal to identify the position of the landing gear at any given time. These switches are designed to detect the physical movement or position of a mechanism and provide feedback to the system. In the case of the landing gear, limit switches are used to determine whether the gear is in the up or down position. When the landing gear reaches its limit, the switch is activated, sending a signal to indicate the gear's position.

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  • 38. 

    The aircraft write up states that the leading edge of the stabilizer does not move down when either horizontal stabilizer trim control switch is put to the NOSE UP position. Where is the best place to start taking meter readings?

    • Check for 28 VDC between pins A and H, B and H, and G and H of the actuator connector plug.

    • Check for 115 VAC between pins A and H, B and H, and G and H of the actuator connector plug.

    • Check for 28 VDC at the up-limit switch with either of the horizontal stabilizer trim control switches actuated

    • Check for 28 VDC at pin F of the actuator connector plug with either of the horizontal stabilizer trim control switches actuated.

    Correct Answer
    A. Check for 28 VDC at pin F of the actuator connector plug with either of the horizontal stabilizer trim control switches actuated.
    Explanation
    The correct answer is to check for 28 VDC at pin F of the actuator connector plug with either of the horizontal stabilizer trim control switches actuated. This is the best place to start taking meter readings because it directly tests the voltage at the actuator connector plug, which is where the issue with the stabilizer not moving down is likely to be. The other options either test for voltage at different pins or at the up-limit switch, which may not provide accurate information about the problem at hand.

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  • 39. 

    When the stick grip trim selector switch is moved to the left, the position of the aircraft left aileron is

    • Up (left wing up)

    • Up (left wing down)

    • Down (right wing up)

    • Down (right wing down)

    Correct Answer
    A. Up (left wing down)
    Explanation
    When the stick grip trim selector switch is moved to the left, it adjusts the trim of the aircraft's ailerons. Ailerons are control surfaces on the wings that help in rolling the aircraft. Moving the switch to the left indicates a desire to trim the left aileron. In order to trim the left aileron, it needs to be moved in the opposite direction, which means the left wing should be moved down. Therefore, the correct answer is "up (left wing down)."

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  • 40. 

    Amplifiers used in the photoelectric fire detector system are sensitive only to

    • Sunlight

    • Light emitted from flash lights

    • Signals with a frequency between 7 and 60 hz

    • Signals with a frequency between 60 and 160 hz

    Correct Answer
    A. Signals with a frequency between 7 and 60 hz
    Explanation
    The amplifiers used in the photoelectric fire detector system are sensitive only to signals with a frequency between 7 and 60 Hz. This means that they can detect and amplify signals within this frequency range, while being less sensitive or unresponsive to signals outside of this range. This frequency range is likely chosen because it corresponds to the typical frequency range of fire-related phenomena, such as flickering flames or smoldering fires. By focusing on this specific frequency range, the amplifiers can effectively detect and amplify the signals associated with fire, increasing the sensitivity and accuracy of the fire detection system.

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  • 41. 

    What is the minimum VAC requirement to energize the emergency power disconnect relay (EPDR)?

    • 90 VAC from A phase

    • 90 VAC from C phase

    • 93 VAC from A phase

    • 93 VAC from C phase

    Correct Answer
    A. 93 VAC from C phase
    Explanation
    The minimum VAC requirement to energize the emergency power disconnect relay (EPDR) is 93 VAC from the C phase. This means that in order for the EPDR to be activated, a voltage of at least 93 VAC needs to be present in the C phase.

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  • 42. 

    If the normal battery is supplying DC to the battery bus and emergency DC bus, your first step in troubleshooting is to

    • Define the problem

    • Take meter readings

    • Know system operation

    • Perform an operational check

    Correct Answer
    A. Know system operation
    Explanation
    Knowing the system operation is the first step in troubleshooting when the normal battery is supplying DC to the battery bus and emergency DC bus. Understanding how the system is supposed to work will help identify any deviations or abnormalities that may be causing the issue. By having a clear understanding of the system operation, it becomes easier to pinpoint the problem and determine the appropriate course of action to resolve it.

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  • 43. 

    In the DC power supply system, the reverse current relays (RCR) deenergize when the potential at the

    • GEN terminal is greater than the indicator terminal

    • GEN terminal is less than the battery terminal

    • GEN terminal is greater than the SW terminal

    • BAT terminal is less than the SW terminal

    Correct Answer
    A. GEN terminal is less than the battery terminal
    Explanation
    The reverse current relays (RCR) in the DC power supply system deenergize when the potential at the GEN terminal is less than the battery terminal. This means that the voltage at the GEN terminal is lower than the voltage at the battery terminal, indicating a reverse current flow. When this occurs, the RCRs are designed to deenergize in order to protect the system from any potential damage or malfunction caused by the reverse current.

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  • 44. 

    To begin troubleshooting a fuel pump inoperative writeup; you would know the system, and then

    • Perform an operational check

    • Limit the malfunction

    • Take meter readings

    • Replace a bad pump

    Correct Answer
    A. Perform an operational check
    Explanation
    Performing an operational check is the first step in troubleshooting a fuel pump inoperative writeup. This involves testing the fuel pump to see if it is functioning properly. By performing this check, you can determine if the fuel pump is the cause of the issue or if there is another problem within the system. Once the operational check is completed, further steps can be taken to limit the malfunction or replace the fuel pump if necessary.

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  • 45. 

    Thermal switches in a fire warning system are normally connected in

    • Series with each other

    • Series with the power source and with the warning light

    • Parallel with the power source and in serious with each other

    • Parallel with the each other and in series with the warning light

    Correct Answer
    A. Parallel with the each other and in series with the warning light
    Explanation
    Thermal switches in a fire warning system are connected in parallel with each other to ensure that if one switch is triggered, it does not affect the operation of the others. However, they are also connected in series with the warning light to ensure that if any of the switches are triggered, the warning light will be activated. This configuration allows for redundancy in the system and ensures that a fire can be detected and indicated even if one or more switches fail to activate.

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  • 46. 

    The auxiliary source selected to power the tie bus in the APU is determined by the

    • Lockout relay (LOR)

    • Bus protection panel (BPP)

    • APU/external power contactor (AEPC)

    • APU/exernal power disconnect contactor (AEDC)

    Correct Answer
    A. APU/external power contactor (AEPC)
    Explanation
    The correct answer is APU/external power contactor (AEPC). The AEPC is responsible for selecting the auxiliary power unit (APU) or external power as the source to power the tie bus. The tie bus is a common electrical bus that connects different power sources and distributes power to various systems in an aircraft. The AEPC ensures that the appropriate power source is selected based on the operational requirements and availability of the APU and external power.

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  • 47. 

    The maximum circuit resistance within a thermocouple circuit is

    • Infinity

    • 5 ohms

    • 50 ohms

    • 500 ohms

    Correct Answer
    A. 5 ohms
    Explanation
    The maximum circuit resistance within a thermocouple circuit is 5 ohms. This is because a thermocouple generates a voltage based on the temperature difference between its two junctions. To accurately measure this voltage, the circuit resistance should be as low as possible to minimize any voltage drops across the circuit. A higher circuit resistance would result in a larger voltage drop, leading to inaccurate temperature measurements. Therefore, a maximum circuit resistance of 5 ohms is recommended for thermocouple circuits.

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  • 48. 

    For the master caution lamp in the master caution system to illuminate,

    • Transistor Q1 must remain at the CUTOFF position

    • Transistor Q2 must remain at the CUTOFF position

    • Controller rectifier SCR2 must forward bias transistor Q2

    • Controller rectifier SCR2 conducts current to forward bias transistor Q2

    Correct Answer
    A. Controller rectifier SCR2 conducts current to forward bias transistor Q2
  • 49. 

    When the cargo and personnel doors close and lock, the door-

    • Open relay will energize

    • Open relay will de-energize

    • Position relay will energize

    • Position relay will de-energize

    Correct Answer
    A. Open relay will de-energize
    Explanation
    When the cargo and personnel doors close and lock, the open relay will de-energize. This means that power supply to the open relay will be cut off, causing it to deactivate.

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Quiz Review Timeline (Updated): Mar 20, 2023 +

Our quizzes are rigorously reviewed, monitored and continuously updated by our expert board to maintain accuracy, relevance, and timeliness.

  • Current Version
  • Mar 20, 2023
    Quiz Edited by
    ProProfs Editorial Team
  • May 27, 2015
    Quiz Created by
    Mirand Rudd
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