Worksheetshệ thống tàu bay ( đề mới ) 2
Total questions: 111
Worksheet time: 56mins
If the torsion link damper reservoir indicates “refill,” what should the technician do
Replace the damper body
Check the downlock actuator
Refill the damper with hydraulic fluid until pressure is reached
Adjust nitrogen pressure in the shock strut
Wing Anti Ice can be tested on ground for maintenance for:
30 minutes
3 minutes
30 seconds after this time it automatically stops to prevent damage to wing leading edge
How is the potable water system pressurized when bleed air is unavailable
By a hydraulic system
By gravity flow
By a manual pump
By an electrical air compressor
Why do jet aircraft use nose landing gear instead of tailwheels
To increase load on the main wheels
To ensure directional stability during takeoff and landing
To simplify gear retraction mechanism
To reduce aircraft weight
When aircraft on ground, which air source is used for pneumatic system?
APU Source
External Air Source
Both of them
If a flight crew oxygen mask does not supply oxygen when removed from its storage box, what should be checked
Pressure gauge in the flight deck
Supply valve inside the storage box
Thermal compensator regulator
Safety disk on the oxygen cylinder
If shock strut pressure is too high during servicing, what should the technician do
Add hydraulic fluid
Replace the laminar flow orifice
Adjust the downlock spring
Bleed nitrogen until the pressure matches the maintenance chart
During a preflight check, a technician switches on the wing anti-ice system on the ground. What happens to the valves
They remain open as long as the switch is on.
They lock in the closed position permanently
They open briefly to check operation and then close
They divert hot air to the windshield
If a technician finds oil on tools while working on the oxygen system, what should they do
Clean the tools to remove the oil before use
Continue using the tools but reduce oxygen pressure
Replace the oxygen cylinder to avoid contamination
Ignore it, as oil does not affect the oxygen system
What is the consequence of using the wrong hydraulic fluid in a shock strut
Nitrogen pressure increases
Seals may be damaged, causing leaks
The strut functions normally without issues
Torsion links become misaligned
Why is a ground safety lock used on the downlock actuator
To align torsion links during oil servicing
To increase hydraulic actuator pressure
To reduce wear on shock strut seals
To prevent unintentional gear retraction during ground maintenance
What is the purpose of the bimetal switch in the drain mast heat system
To detect ice buildup on the fuselage
To regulate temperature by switching heating on or off
To control the wiper motor speed
To activate the rain repellent system
What is the role of the solenoid in a pressure-operated anti-ice valve
To monitor the valve’s temperature
To control air pressure to open or close the valve
To heat the valve during ground operations
To manually override the valve position
What happens to the vibration frequency of an optical ice detector’s probe tip when ice builds up
The frequency increases due to added weight
The frequency remains unchanged
The frequency stops completely
The frequency decreases due to added weight
Why should oxygen cylinder valves be opened slowly
To prevent oxygen leakage
To avoid pressure buildup that could cause ignition or explosion
To reduce wear on the valve
To ensure even oxygen flow to the mask
The torque links align the main fitting and the sliding tube for:
Vertical movement between the parts to occur
Lateral movement between the parts to occur
To prevent Lateral movements
What is the advantage of electronic temperature control circuits over bimetal switches in electrical anti-ice systems
Bimetal switches are more precise and durable
Both systems are equally effective with no differences
Electronic circuits require more maintenance
Electronic circuits offer precise control and no mechanical wear
What prevents freezing in the waste water system’s drain mast
Manual draining
Insulation material
Chemical additives
Electrical heating
Why does the rebound valve restrict oil flow during shock strut extension
To increase gas pressure in the strut
To control rebound rate and prevent rapid extension
To reduce the need for nitrogen charging
To lubricate the inner cylinder
What is the safety precaution to be taken when working on L/G systems:
Obey all the AMM safety procedures
As in A plus Install safety devices and Warning Notices all time
No any precautions required
What is the impact of a permanently closed contact in a window heat system’s temperature control circuit
It leads to overheating, mitigated by an overheat protection circuit
It has no effect on system performance
It reduces the heating power to zero
It causes the system to shut down completely
What activates the electrical air compressor in the potable water system
A temperature sensor
A manual override switch
A pressure switch when pressure drops below 30 psi
A water quantity transmitter
During engine idle, which bleed port ensures sufficient pressure for the pneumatic system
Ground connector port
High Pressure port
Intermediate Pressure port
Fan air port
When should a pilot avoid switching on the windshield wiper
During approach in heavy rain
When the aircraft is on the ground
During takeoff in light rain
At airspeeds above 250 knots or on a dry windshield
What could happen if the check valve fails during high-pressure valve operation
Reduced cabin pressurization
Reverse flow causing compressor stall
Increased APU bleed air flow
Overheating of the precooler
Why is a tapered metering pin used in a shock strut instead of a linear one
To achieve progressive damping, reducing stroke length
To simplify the oil servicing process
To increase nitrogen pressure in the strut
To provide constant fluid flow during compression
The Aircraft tires filled with:
Oxygen (O2)
Nitrogen (N2)
Air
Why does the electronic ice detector automatically activate anti-ice systems, unlike the optical ice detector
It requires manual activation by the pilot
It uses a simpler vibration mechanism
It senses ice and generates signals without pilot intervention
It is located in the cockpit for pilot visibility
The Brake accumulator can supply power for:
Emergencies
Abnormal operation
Normal operation
Why are downlock sensors important in the gear locking mechanism
They indicate when gear is down and locked
They lubricate the shock strut bearings
They control hydraulic fluid flow
They prevent wheel shimmy during taxi
What is the purpose of the water heater in the lavatory water system
To drain waste water
To filter potable water
To provide hot water to the washbasin
To pressurize the water tanks
Where are potable water tanks typically located on an aircraft
In the pressurized underfloor area of the fuselage
In the galley area
In the cargo compartment
In the wings
What is the primary function of the potable water system on an aircraft
To supply water for lavatories and galleys
To pressurize the cabin
To remove waste from toilets
To cool electrical components
If the fan air valve is stuck closed, what is the likely effect on the pneumatic system
Overheating of engine bleed air
Increased cabin pressurization
Backflow into the compressor
Reduced manifold pressure
Why is the inner cylinder of a shock strut made of high-strength steel
To reduce weight while maintaining strength
To increase shock strut weight
To increase hydraulic fluid capacity
To simplify gear retraction mechanism
Why does the Airbus crew oxygen system require activation of the crew supply switch
To prevent oxygen from reaching the passenger cabin
To activate a solenoid valve allowing oxygen flow to the cockpit
To check oxygen flow
What component on the water service panel connects the external water supply to the aircraft?
Drain valve handle
Water quantity indicator
Fill fitting with a quick disconnect nozzle
T-handle
Why can the engine anti-ice system be activated on the ground, unlike the wing anti-ice system?
It relies on electrical power only
It is controlled by a single switch
It uses less hot air than the wing system
It is critical for engine protection even when stationary
If the continuous-flow mask in the portable oxygen system does not supply oxygen, what should be checked?
Thermal compensator in the bottle
Safety disk on the oxygen bottle
Connection between the mask and the bottle outlet
Flow indicator in the storage container
If the overpressure valve fails to close at 85 psi, what could be the consequence?
Backflow into the IP stage
Increased engine thrust
Potential damage to pneumatic ducts or consumers
Reduced cooling efficiency
What happens to the nose gear if there is no hydraulic power during extension?
Automatically locks in the retracted position
It extends due to gravity and airflow
It remains retracted and cannot extend
Requires manual extension by the pilot
What is the advantage of the emergency free-fall extension system?
Simplifies steering mechanism
Reduces aircraft weight
Requires hydraulic power to operate
Allows gear extension without hydraulics, using gravity
What is the purpose of the liquid separator in the vacuum toilet system?
To remove moisture and waste particles from tank air
To heat the drain lines
To pressurize the waste tank
To flush the toilet bowl
Why does the window heat system use a ramp function when activated?
To rapidly heat the windshield to maximum temperature
To alternate between high and low wiper speeds
To slowly increase heating power to prevent stress on the glass
To reduce the aircraft’s electrical load
What indicates a system fault on the bleed panel in the cockpit?
Engine thrust increase
Cross-bleed valve closure
Illumination of a fault light
APU shutdown
If the nose gear door remains open after extension, which component should be checked?
Uplock roller
Door actuator
Drag strut
Shock strut seals
Why is the wing anti-ice system designed to operate symmetrically on both wings?
To increase the aircraft’s weight evenly
To reduce the need for hot air from the engines
To ensure balanced aerodynamic performance
To simplify the rain removal process
.Potable water service Panel located in A320 Family at
Only one
Two, the second one at the center of the Aircraft
Three draining panels.
If an oxygen cylinder’s pressure drops below 50 psi, what should the technician do?
Remove the cylinder and send it to the shop for moisture inspection
Continue using the cylinder if pressure increases again
Immediately refill the cylinder
Check the regulator valve before refilling
What should a technician do if a pilot reports poor visibility despite using the rain repellent system?
Adjust the wing anti-ice valve pressure
Inspect the windshield coating and wiper adjustments
Check the engine anti-ice valve position
Test the probe heat system
The Alternate braking powered by:
Blue hydraulic system
Green Hydraulic system
Yellow hydraulic system
In Alternate Braking the Brake pressure indicated at:
ECAM-EWD
Triple Pressure indicator
ECAM-WHEEL page
HP bleed used when:
Engines are low power settings
At all-time either low or high-power settings
As in A, during cruise for engine efficiency the High-Pressure Valve (HPV) is closed
Compared to chemical systems, why does the gaseous system require a flow control unit?
To heat the oxygen before it reaches the mask
To prevent oxygen leakage from the cylinder
To trigger a chemical reaction for oxygen generation
To reduce cylinder oxygen pressure and open PSU doors
If the landing gear doors do not close after gear retraction, what should be checked first?
Hydraulic supply to the door actuators
Torsion link alignment
Main gear brakes
Shock strut seals
If a pressure regulating valve in the wing anti-ice system fails to maintain 20 psi, what is a likely consequence?
The engine anti-ice system shuts down
The windshield wiper speed increases
The system may not prevent ice buildup effectively
The rain repellent fluid is overpressurized
The AOA/TAT/Pitot probes and Static port are heated for anti-icing by:
Electrically
No heating required
Bleed air
The Lavatory/Toilet Service Panel Located in A320 Family:
At the Center of Aircraft
At Rear Left Hand Side
At rear Right Hand Side
What is the purpose of the downlock mechanism in the main gear?
Controls gear extension speed
Releases the gear in case of free-fall deployment
Keeps gear retracted and locked during flight
Ensures gear is down and locked on the ground
Which system is typically not powered by pneumatic energy?
Wing anti-icing system
Primary flight controls
Cabin air conditioning
Engine starter
During inspection, the technician finds that the landing gear does not fully extend. What should be checked?
Torsion link damper
Shock strut bearing
Selector valve in the hydraulic system
Nosewheel steering cable
If an oxygen cylinder is over-pressurized, why does the safety disk rupture instead of the cylinder cracking?
The cylinder has a pressure regulator to prevent overpressure
The safety disk is designed to burst at a lower pressure than the cylinder’s failure point
The cylinder is made of stronger material than the safety disk
The safety disk automatically vents oxygen to lower pressure
Why is the drag strut important for main landing gear stability?
It stabilizes the shock strut fore and aft
It reduces hydraulic fluid demand
It locks the gear in the retracted position
It controls gear retraction speed
What component monitors the temperature downstream of the pre-cooler?
Leak detection sensor
Flow sensor
Thermostat
Pressure transducer
If the bleed air switch in the cockpit is off, what happens to the bleed valve?
Adjusts fan air flow
Closes due to solenoid action
Opens fully
Isolates the cross-bleed manifold
If the relief valve on a portable oxygen bottle activates, what could be the cause?
The smoke hood is damaged
High temperature caused the bottle pressure to rise
Faulty regulator caused oxygen leakage
The bottle was overfilled with oxygen
Why can heat buildup in oxygen lines lead to fire or explosion?
Heat damages the regulator valve, causing leaks
Heat reduces oxygen dryness, causing freezing
Heat combined with compressed oxygen facilitates combustion
Heat increases oxygen pressure, causing pipe rupture
During engine start, how is reverse flow through the bleed valve enabled on some aircraft?
By increasing APU bleed air pressure
By closing the fan air valve
By manually opening the cross-bleed valve
By a solenoid allowing downstream pressure to the actuator
What is the effect of a high contact angle between water droplets and the windshield when using rain repellent?
Water droplets adhere more strongly to the windshield
Water droplets freeze on the windshield
Water droplets increase pilot visibility without removal
Water droplets are easily blown away by the airstream
L/G Extension and Retraction controlled by:
Manually by cables
Pulleys
Two computers called LGCIU 1 & 2
A320 Landing Gears (L/G s) are:
Pneumatically operated and hydraulically controlled
Hydraulically operated and electrically controlled
Electrically operated and hydraulically controlled
The Normal braking system uses hydraulic from:
Green System
Blue System
Yellow system
What is the purpose of using multiple wheels on the main landing gear of large aircraft such as the Boeing 747?
To distribute main gear load, allowing operation on more runways
To increase aircraft speed on the runway
To provide additional braking force
To reduce need for hydraulic actuators
A technician is troubleshooting a window heat system that shuts down automatically. What is a likely cause?
A failure in the wiper motor
Ice buildup on the wing leading edge
A sensor failure or controller malfunction
Low pressure in the pneumatic system
Why does ice buildup on an aircraft’s wing leading edge reduce aerodynamic quality
It decreases the aircraft’s weight
It alters the wing’s shape, decreasing lift and increasing drag
It improves airflow over the wing
It increases lift and reduces drag
What material are potable water tanks typically made of
Stainless steel
Carbon fiber
Aluminum alloy
Glass fibre reinforced plastic
Why are filters used where regulating or sensing air is bled from the duct
To increase air pressure
To prevent contamination of regulating components
To reduce airflow to consumers
To cool the bleed air
Why are engine anti-ice systems critical for jet aircraft
They cool the engine inlet during high-speed flight
They regulate the aircraft’s weight during icing conditions
They prevent ice buildup that could disturb airflow and damage engine components
They improve fuel efficiency in icing conditions
The computer Responsible for Normal Braking operation is:
Alternate Braking Control Unit (ABCU)
Landing Gear Control and Interface Unit (LGCIU)
Braking/Steering Control Unit (BSCU)
If the bleed valve fails to close during an overtemperature condition, what is the likely consequence
Potential damage to downstream pneumatic components
Backflow into the APU
Increased cabin pressurization
Reduced engine thrust
What must a technician do before replacing a component in the potable water system
Activate the vacuum system
Depressurize the pneumatic system
Heat the water heater
Open the drain valve
When an aircraft is on the ground with no engines or APU running, which source supplies the pneumatic system
High Pressure Ground Connector
Fan air duct
Engine bleed air
APU bleed air
Why do portable oxygen bottles have an integrated pressure relief valve
To reduce pressure to safe levels if the regulator fails
To increase oxygen flow to the mask
To cool the bottle in high-temperature environments
To prevent oxygen leakage during storage
In what situation would a technician use the manual override function of a thermal anti-ice valve
To clean the windshield
During normal flight operations
To test the rain repellent system
When there is a valve or system failure
The Bleed system monitored by Two Bleed Monitoring Computers (BMC 1 and BMC 2):
As in A & B, Both the BMC 1 & 2 exchange data at all time (Cross Talk)
One BMC for each engine bleed system
If one BMC fails the other takes over for monitoring functions
During a gear retraction test, the gear does not lock in the up position. What should be checked
Shock strut bearing
Drag strut
Uplock hook
Torsion link damper
How does the optical ice detector inform pilots of icing conditions
It vibrates and sends an electrical signal to the engines
It sprays rain repellent fluid on the windshield
It is visible to pilots, indicating ice buildup for manual activation
It automatically adjusts the aircraft’s altitude
What is the function of torsion links in the main landing gear
Control hydraulic fluid flow inside the shock strut
Connect the actuator to the shock strut
Allow the inner cylinder to rotate freely
Prevent inner cylinder rotation while allowing axial movement
What standard size is the external pneumatic connector?
4 inches
5 inches
3 inches
If a portable oxygen bottle has low pressure, why should it not be refilled immediately
The bottle must be heated before refilling
The regulator must be replaced first
Low pressure may indicate moisture ingress, which could damage the bottle
Low pressure does not affect the bottle
When is the passenger oxygen system automatically activated
When cylinder pressure drops below 50 psi
When the aircraft reaches 33,000 ft
When the flight crew activates the emergency switch
When cabin pressure altitude exceeds 14,000 ft
At low engine speeds, which bleed air port is primarily used to supply the pneumatic system
Intermediate Pressure port
High Pressure port
Cross-bleed port
Fan air port
If the green plastic disk at the overboard discharge port is broken, how can the faulty oxygen cylinder be identified
Replace all cylinders in the system
Check the pressure gauge of each oxygen cylinder
Inspect the regulator valve in the distribution line
Measure the temperature of each cylinder
How does the windshield wiper system improve pilot visibility in rain
By applying a hydrophobic coating to repel water
By heating the windshield to evaporate water
By increasing the aircraft’s speed to blow water away
By mechanically removing water from the windshield
What is the primary function of the waste water system
To remove waste water from washbasins and galleys
To flush the toilet system
To store toilet waste
To pressurize the potable water system
Compared to continuous-flow masks, why are demand masks more suitable in smoky environments
Demand masks deliver higher pressure, pushing out smoke
Demand masks provide oxygen only during inhalation, conserving supply
Demand masks do not require a portable oxygen bottle
Demand masks are lighter and easier to use
If a chemical oxygen generator fails to supply oxygen after the lanyard is pulled, what is the likely cause
The regulator valve on the cylinder is faulty
The distribution line is blocked
Oxygen pressure in the cylinder is too low
The chemical reaction did not initiate due to trigger failure
If a leak is detected in the forward section of the potable water system, what should a technician do
Activate the vacuum toilet system
Close the forward shut-off valve
Open the aft shut-off valve
Drain the waste water system
Why does the nose gear provide better directional stability than tailwheel gear on wet runways
Center of gravity is ahead of the main wheels, creating a restoring moment
Nose gear retracts inward, reducing drag
Nose gear has brakes to prevent skidding
Center of gravity is behind the main wheels, creating a destabilizing moment
The L/G doors are:
Hydraulically and mechanically operated doors
Hydraulically and electrically operated doors
Hydraulically and pneumatically operated doors
What role do landing gear doors play in aircraft performance
Support aircraft weight on the ground
Increase aircraft lift
Reduce noise and parasitic drag, improving speed and fuel efficiency
Provide additional control capability
If a leak is detected in the left wing pneumatic duct, what does the pneumatic controller likely do
Opens the cross-bleed valve
Shuts off the affected engine bleed air system
Activates the APU bleed valve
Increases fan air valve opening
What is the typical capacity of a portable oxygen bottle
3200 liters at 1850 psi
310 liters at 1800 psi
1100 liters at 2600 psi
500 liters at 1400 psi
How is the waste tank drained during servicing of the vacuum toilet system
By pressurizing the potable water system
By activating the vacuum blower
By opening the flush valve
By pulling the drain valve handle on the service panel
Where is the cross-bleed manifold typically located
In the APU compartment
In the fuselage
In the wing leading edge
In the engine pylon
How does the water quantity transmitter measure water levels in the tank
By a float valve
By a temperature sensor
By a capacitance probe
By a pressure sensor
What is the purpose of the fluid metering device in the main gear actuator
To control extension and retraction speed, preventing impact
To lock the gear in the down position
To maintain constant nitrogen pressure
To steer the aircraft during taxi
If the main gear actuator fails to retract the gear, what should be checked first
Torsion link damper
Nitrogen level in the shock strut
Nosewheel steering system
Hydraulic pressure supply to the actuator
What is the consequence of a failed uplock actuator in the uplock mechanism
Nosewheel steering becomes inoperative
Gear deploys too quickly during landing
Shock strut becomes over-pressurized
Gear may not fully retract, increasing drag
The accumulator Pressure can be used for:
Maximum of 7 full brake pedal applications
Maximum of 5 full brake pedal applications
Maximum of 2 full brake pedal applications
Why does the gaseous oxygen system use a bleed relief valve in the distribution line
To increase oxygen flow to masks far from the cylinder
To control cylinder pressure
To prevent pressure buildup causing unintended mask deployment
To cool the oxygen before it reaches the masks
