1.
(801) How does a liquid fire-extinguishing agent extinguish an aircraft fire?
Correct Answer
C. Removes oxygen from the fire.
Explanation
A liquid fire-extinguishing agent extinguishes an aircraft fire by removing oxygen from the fire. Oxygen is necessary for combustion, so by eliminating or reducing the oxygen supply, the fire cannot sustain itself and is extinguished. This can be achieved by creating a barrier between the fire and the surrounding air, preventing the fire from accessing oxygen.
2.
(801) A gaseous nitrogen (N2) charge is added to a liquid fire-extinguishing agent to
Correct Answer
B. Expel the agent from its bottle.
Explanation
The gaseous nitrogen charge is added to a liquid fire-extinguishing agent in order to expel the agent from its bottle. When the fire extinguisher is discharged, the pressure from the gaseous nitrogen forces the liquid agent out of the bottle, allowing it to be sprayed onto the fire. This helps to effectively extinguish the fire by covering it with the extinguishing agent.
3.
What component holds a liquid agent and a nitrogen charge in a liquid-agent fire extinguisher
container?
Correct Answer
B. Frangible disc.
Explanation
The frangible disc is the component that holds a liquid agent and a nitrogen charge in a liquid-agent fire extinguisher container. A frangible disc is a thin, breakable disc that seals the container and prevents the agent and charge from escaping. When the extinguisher is activated, the pressure builds up inside the container, causing the frangible disc to rupture and release the agent and charge. This allows the extinguisher to effectively suppress the fire.
4.
(801) The frangible disc is undercut into pie shaped sections in a liquid-agent fire extinguisher
container to
Correct Answer
B. Break cleanly into large pieces.
Explanation
The frangible disc is undercut into pie-shaped sections in a liquid-agent fire extinguisher container in order to break cleanly into large pieces. This design allows for easy and efficient activation of the extinguisher when needed, as the disc can be easily broken into large fragments. This ensures that the extinguishing agent can be quickly and effectively released into the fire, maximizing its effectiveness.
5.
(802) A flashing red light on the fire emergency control T-handle indicates this has happened.
Correct Answer
A. An overheat condition.
Explanation
A flashing red light on the fire emergency control T-handle indicates an overheat condition. This means that there is excessive heat in the system or equipment, which could potentially lead to a fire if not addressed. The flashing red light serves as a warning signal to alert the operator or user that there is a risk of overheating and immediate action should be taken to prevent any further damage or potential fire hazard.
6.
(802) If the container pressure becomes too low in a T-handle liquid-agent fire extinguishing
system, then a
Correct Answer
B. Pressure switch closes.
Explanation
In a T-handle liquid-agent fire extinguishing system, if the container pressure becomes too low, it indicates that there is not enough pressure to effectively discharge the liquid agent. In order to prevent further loss of pressure, a pressure switch closes, which helps maintain the pressure within the container.
7.
(803) An aircraft’s liquid coolant system keeps components cool by
Correct Answer
A. Cycling through the components.
Explanation
The correct answer is "cycling through the components." An aircraft's liquid coolant system keeps components cool by continuously circulating the coolant through the components. This allows the coolant to absorb heat from the components and carry it away, preventing overheating and ensuring proper functioning of the aircraft's systems.
8.
(803) If air that is trapped in a liquid coolant system is not bled out of the expansion relief valve it
Correct Answer
D. Reduces the cooling capability of the coolant.
Explanation
If air is trapped in a liquid coolant system and not bled out of the expansion relief valve, it reduces the cooling capability of the coolant. Air bubbles in the coolant can create pockets of insulation, preventing efficient heat transfer and reducing the coolant's ability to absorb and dissipate heat. This can lead to overheating of the system and potential damage to the components being cooled.
9.
(803) What valve component of an aircraft liquid coolant system is positioned by the temperature
of the coolant?
Correct Answer
A. Thermal pilot.
Explanation
The valve component of an aircraft liquid coolant system that is positioned by the temperature of the coolant is called a thermal pilot. This means that the thermal pilot valve adjusts its position based on the temperature of the coolant, allowing for proper regulation and control of the coolant flow.
10.
(804) Over-torquing clamps, when maintaining an aircraft liquid coolant system, causes this to
happen with the clamps’ components.
Correct Answer
D. Damage or failure
Explanation
Over-torquing clamps in an aircraft liquid coolant system can cause damage or failure to the clamps' components. This excessive torque can lead to the clamps becoming weakened or distorted, resulting in potential leaks or complete failure of the clamps. This can be detrimental to the proper functioning of the coolant system and may require repair or replacement of the damaged components.
11.
(804) The purpose of purging the servicing unit supply hose in an aircraft liquid coolant system is
to
Correct Answer
C. Prevent air from entering the system.
Explanation
The purpose of purging the servicing unit supply hose in an aircraft liquid coolant system is to prevent air from entering the system. This is important because air bubbles in the coolant can cause cavitation, which can lead to decreased cooling efficiency and potential damage to the system. By purging the supply hose, any air trapped in the system can be removed, ensuring that only coolant flows through the system and preventing the negative effects of air bubbles.
12.
(804) How many gallons of liquid coolant should initially be pumped into the aircraft liquid
coolant system with the radar shunt hose installed?
Correct Answer
C. 1 1/2
Explanation
The correct answer is 1 1/2. The question is asking for the amount of liquid coolant that should be initially pumped into the aircraft liquid coolant system with the radar shunt hose installed. The answer suggests that 1 1/2 gallons of liquid coolant should be pumped in initially.
13.
(804) When servicing the aircraft liquid coolant system, leave the used can of coolant fluid
installed on the servicing unit to prevent this from happening to the unit.
Correct Answer
D. Contamination.
Explanation
When servicing the aircraft liquid coolant system, leaving the used can of coolant fluid installed on the servicing unit can lead to contamination. This is because the used can may contain impurities or contaminants that can mix with the new coolant fluid, thereby compromising its quality. To prevent this from happening, it is important to remove the used can and properly dispose of it before installing a new one to ensure the coolant system remains uncontaminated.
14.
(805) Why are multiplace life raft cylinders wire-wound and dip-soldered?
Correct Answer
B. Adds strength to the cylinder.
Explanation
Multiplace life raft cylinders are wire-wound and dip-soldered to add strength to the cylinder. Wire-winding involves wrapping a wire tightly around the cylinder, which helps to reinforce and strengthen it. Dip-soldering, on the other hand, involves coating the cylinder with a layer of solder, which further enhances its strength. By incorporating these techniques, the cylinders become more durable and able to withstand the harsh conditions they may encounter during use, ensuring the safety of those relying on the life raft.
15.
(805) What component of a life raft inflation cylinder assembly keeps carbon dioxide (CO2)
within the cylinder and permits an unrestricted flow of CO2 to the life raft?
Correct Answer
D. Discharge valve.
Explanation
The discharge valve is the component of a life raft inflation cylinder assembly that keeps carbon dioxide (CO2) within the cylinder and allows for an unrestricted flow of CO2 to the life raft. It is responsible for controlling the release of the gas from the cylinder into the raft, ensuring that it inflates properly and efficiently. The other options, such as the diffuser plug, seating sleeve, and cartridge filter, do not perform this specific function.
16.
(805) Actuating this component normally releases carbon dioxide (CO2) from a life raft cylinder
into a life raft.
Correct Answer
A. Cam.
Explanation
The correct answer is Cam. A cam is a mechanical component that is responsible for actuating or controlling the movement of other parts. In this case, when the cam is actuated, it triggers the release of carbon dioxide from a life raft cylinder into the life raft. The cam mechanism is designed to provide a reliable and controlled release of the gas to inflate the life raft in emergency situations.
17.
(806) When you are charging a multiplace life raft inflation assembly, do not reposition the
assembly on a platform because moving it may
Correct Answer
B. Change the hose weight amount.
Explanation
When charging a multiplace life raft inflation assembly, it is important not to reposition the assembly on a platform because moving it may cause damage to the life raft. This means that changing the hose weight amount is not the correct answer. The other options, such as causing the charging hose to detach or requiring a new check valve control head, are not mentioned in the explanation, so it is not clear why they would be incorrect.
18.
(806) What must you do to ensure your safety when you recharging life raft inflation cylinders?
Correct Answer
A. Charge in a well ventilated area.
Explanation
To ensure safety when recharging life raft inflation cylinders, it is important to charge them in a well-ventilated area. This is necessary to prevent the accumulation of potentially harmful gases or fumes. Ventilation helps to dissipate any gases that may be released during the charging process, reducing the risk of inhalation and potential harm to individuals in the area. This precaution is crucial to maintain a safe working environment and protect the health and well-being of those involved in the recharging process.
19.
(807) Oxygen in its natural state is
Correct Answer
A. Colorless, tasteless, and odorless.
Explanation
Oxygen in its natural state is colorless, meaning it does not have any color. It is also tasteless, meaning it does not have any specific taste. Finally, it is odorless, meaning it does not have any smell.
20.
(807) Which part of the body usually suffers first from the effects of hypoxia, which is the lack of
oxygen at high altitudes?
Correct Answer
B. Eyes.
Explanation
At high altitudes, the lack of oxygen, known as hypoxia, can have various effects on the body. The eyes are usually the first part of the body to suffer from these effects. This is because the eyes have a high demand for oxygen and are very sensitive to changes in oxygen levels. The lack of oxygen can cause blurred vision, difficulty focusing, and even temporary vision loss. Therefore, the eyes are more susceptible to the effects of hypoxia compared to other parts of the body.
21.
(807) This valve prevents a complete loss of oxygen in a low-pressure gaseous oxygen system
Correct Answer
B. Check.
Explanation
The correct answer is "Check." In a low-pressure gaseous oxygen system, a check valve is used to prevent a complete loss of oxygen. A check valve allows the flow of oxygen in one direction but prevents it from flowing back in the opposite direction. This ensures that oxygen is only able to flow into the system and not escape, thereby preventing a complete loss of oxygen. A check valve is commonly used in oxygen systems to maintain the integrity and safety of the system.
22.
(807) What cellulose tape colors identify supply and distribution tubing for aircraft oxygen
systems?
Correct Answer
C. Green and white.
Explanation
Green and white cellulose tape colors are used to identify supply and distribution tubing for aircraft oxygen systems. This color combination is commonly recognized and used in aviation to differentiate oxygen-related components from other systems. The use of green and white tape helps ensure proper identification and maintenance of the oxygen system, promoting safety and efficiency in aircraft operations.
23.
(807) What valve is required to decrease system pressure in a high-pressure gaseous oxygen
system?
Correct Answer
D. Reducer.
Explanation
A reducer valve is required to decrease system pressure in a high-pressure gaseous oxygen system. This valve is specifically designed to reduce the pressure of the gas flowing through the system. It helps to ensure that the pressure remains within safe limits and prevents any potential damage or hazards that may occur due to high pressure.
24.
(807) In a high-pressure oxygen system, the tubing between the filler valve and the pressure
reducer valve is made of this type alloy.
Correct Answer
C. Copper.
Explanation
In a high-pressure oxygen system, the tubing between the filler valve and the pressure reducer valve is made of copper. Copper is commonly used in high-pressure oxygen systems because it is resistant to corrosion and can withstand the high pressure and purity requirements of the system. Copper also has good thermal conductivity, which allows for efficient heat transfer in the system. Additionally, copper is a non-sparking material, making it safer to use in oxygen-rich environments where sparks could potentially cause a fire or explosion.
25.
(807) What does the molecular sieve oxygen generating system (MSOGS) concentrator supply to
the OXYGEN regulator control panel?
Correct Answer
C. 93 percent oxygen-enriched gas.
Explanation
The molecular sieve oxygen generating system (MSOGS) concentrator supplies 93 percent oxygen-enriched gas to the OXYGEN regulator control panel. This means that the gas being supplied has a higher concentration of oxygen compared to the surrounding air. This is important for providing a sufficient amount of oxygen for various applications, such as medical use or aircraft systems that require oxygen for proper functioning.
26.
(808) Liquid oxygen converts to gaseous oxygen at an expansion ratio of
Correct Answer
D. 860 to 1.
Explanation
Liquid oxygen converts to gaseous oxygen at an expansion ratio of 860 to 1. This means that when liquid oxygen is converted into a gas, its volume increases by a factor of 860. This expansion ratio is a measure of how much the substance expands when it changes state from a liquid to a gas.
27.
(808) What pressure valve component in a 70 pound per square inch (psi) liquid oxygen (LOX)
system has the ability to draw gaseous oxygen from the head pressure, which builds up 10 pounds
per square inch above a normal setting?
Correct Answer
D. Opening
Explanation
In a 70 psi liquid oxygen system, the pressure valve component that has the ability to draw gaseous oxygen from the head pressure is the "Opening". This means that when the pressure builds up 10 psi above the normal setting, the opening component allows the release of gaseous oxygen to prevent overpressure in the system.
28.
(808) What is the handle on a manually operated buildup and vent valve designed to prevent on an
aircraft liquid oxygen (LOX) system?
Correct Answer
C. Filler access door from closing in the vent position
Explanation
The handle on a manually operated buildup and vent valve is designed to prevent the filler access door from closing in the vent position. This means that when the valve is operated, it ensures that the filler access door remains open, allowing for the rapid venting of system pressure. This is important in an aircraft liquid oxygen (LOX) system as it prevents pressure buildup and ensures the safe release of excess pressure.
29.
(808) This is a disadvantage of a continuous-flow oxygen regulator compared to the pressuredemand
system in a liquid oxygen system (LOX).
Correct Answer
A. Wastes oxygen.
Explanation
A continuous-flow oxygen regulator wastes oxygen because it delivers a constant flow of oxygen regardless of whether the user is inhaling or not. This means that oxygen is being continuously released even when it is not being used, leading to wastage of oxygen.
30.
(808) What component in the pressure-demand oxygen regulator causes 100 percent oxygen to be
delivered to the user when the cabin altitude of an aircraft reaches 30,000 feet?
Correct Answer
C. Diluter aneroid.
Explanation
The diluter aneroid is the component in the pressure-demand oxygen regulator that causes 100 percent oxygen to be delivered to the user when the cabin altitude of an aircraft reaches 30,000 feet. This device is responsible for regulating the oxygen flow based on the altitude, ensuring that the user receives the appropriate amount of oxygen to maintain safe breathing at high altitudes.
31.
(808) What causes oxygen and pressure breathing to be available in the pressure breathing for G
(PBG) position once the PBG/ON/OFF toggle is placed in that position?
Correct Answer
D. Positive signal from the anti-G valve.
Explanation
When the PBG/ON/OFF toggle is placed in the PBG position, oxygen and pressure breathing become available in the pressure breathing for G (PBG) position. This is because a positive signal is received from the anti-G valve. The anti-G valve is responsible for regulating the flow of oxygen and pressure during high-G maneuvers, ensuring that the pilot receives the necessary oxygen and pressure to prevent hypoxia and maintain consciousness. Therefore, the positive signal from the anti-G valve allows for the availability of oxygen and pressure breathing in the PBG position.
32.
(808) Which oxygen system allows oxygen to flow automatically to the distribution system when
cabin altitude reaches 12,500 feet?
Correct Answer
B. Troop.
Explanation
The correct answer is Troop. The troop oxygen system allows oxygen to flow automatically to the distribution system when the cabin altitude reaches 12,500 feet. This system is designed to provide oxygen to passengers or troops on board the aircraft in case of a high cabin altitude, ensuring their safety and well-being during the flight.
33.
(809) If you find oxygen system tubing within 2 inches of aircraft control cables, your next step is
to
Correct Answer
B. Bend or reroute the tubing.
Explanation
If oxygen system tubing is found within 2 inches of aircraft control cables, the next step is to bend or reroute the tubing. This is necessary to ensure that the tubing does not interfere with the control cables and potentially cause damage or malfunction. By bending or rerouting the tubing, the risk of any potential issues or accidents is minimized, ensuring the safety and proper functioning of the aircraft.
34.
(810) When replacing oxygen tubing, use clamps to support it near all bends and at least every
Correct Answer
B. 15 inches.
Explanation
When replacing oxygen tubing, it is important to use clamps to support it near all bends and at least every 15 inches. This is necessary to prevent kinks or bends in the tubing, which can obstruct the flow of oxygen and potentially lead to a dangerous situation for the patient. By clamping the tubing at regular intervals, it ensures that the tubing remains straight and unobstructed, allowing for a consistent and uninterrupted flow of oxygen.
35.
(810) A liquid oxygen (LOX) component is being replaced and you are ready to install the pipethread
fittings. Your next step is to
Correct Answer
D. Apply a small amount of anti-seize tape to the first three threads.
Explanation
The correct answer is to apply a small amount of anti-seize tape to the first three threads. This step is necessary to ensure that the pipethread fittings can be properly installed and secured. The anti-seize tape helps to prevent the threads from seizing or getting stuck, making it easier to install and remove the fittings in the future. By applying the tape to the first three threads, it ensures that the tape is in the correct position to provide maximum effectiveness.
36.
(811) You must purge an aircraft’s gaseous oxygen (GOX) system by
Correct Answer
C. Using a gaseous oxygen-servicing trailer.
37.
(811) On a gaseous oxygen (GOX) servicing trailer, you control the flow of oxygen by
Correct Answer
B. Opening the servicing valves manually.
Explanation
On a gaseous oxygen (GOX) servicing trailer, the flow of oxygen is controlled by opening the servicing valves manually. This means that the valves responsible for the release of oxygen are operated by hand to regulate the flow. This method allows for precise control over the amount of oxygen being released from the trailer.
38.
(811) You are ready to clean components from a gaseous oxygen (GOX) cart. What is the first
step?
Correct Answer
B. Remove any dust or loose debris with filtered air.
Explanation
The correct answer is to remove any dust or loose debris with filtered air. This is the first step because it is important to ensure that the components are free from any contaminants before proceeding with the cleaning process. Using filtered air helps to prevent any further contamination and ensures that the components are clean and ready for further cleaning or maintenance procedures.
39.
(812) When performing a service test on a low-pressure gaseous oxygen system, after filling the
system, you must
Correct Answer
D. Wait for the system to cool for one hour.
Explanation
When performing a service test on a low-pressure gaseous oxygen system, it is necessary to wait for the system to cool for one hour. This is because filling the system with oxygen can cause it to heat up, and waiting for it to cool ensures that accurate measurements can be taken. Recording the oxygen gauge pressure immediately or recording the ambient temperature immediately may not give accurate readings as the system needs time to stabilize. Waiting for three hours to cool is not necessary and one hour is sufficient for the system to reach a stable temperature.
40.
(812) After performing an evaporation loss test on a liquid oxygen system, you fill the converter
to its capacity with liquid oxygen and
Correct Answer
A. Allow it to stabilize 2 hours before taking next reading.
Explanation
After performing an evaporation loss test on a liquid oxygen system, it is necessary to allow the converter to stabilize before taking the next reading. This is because the converter needs time to reach a steady state after being filled with liquid oxygen. Allowing it to stabilize for 2 hours ensures that any fluctuations in pressure or temperature have settled, providing an accurate reading for the next measurement.
41.
(813) Heat gain and liquid oxygen (LOX) boil-off is minimized in the annular space of a TMU–
27/M LOX storage and transfer-servicing cart using this type insulation.
Correct Answer
B. Aluminized polyester film.
Explanation
Aluminized polyester film is used as insulation in the annular space of a TMU-27/M LOX storage and transfer-servicing cart to minimize heat gain and liquid oxygen (LOX) boil-off. This type of insulation is effective in preventing heat transfer and maintaining the temperature inside the cart. The aluminized coating on the polyester film reflects heat radiation, while the polyester film itself provides thermal insulation. This combination helps to minimize heat gain and reduce the boil-off of LOX, ensuring the safe storage and transfer of the liquid oxygen.
42.
(813) The transfer hose on a liquid oxygen (LOX) cart is made from stainless steel and this type
alloy.
Correct Answer
A. Bronze.
Explanation
The transfer hose on a liquid oxygen (LOX) cart is made from bronze. Bronze is a suitable material for this application because it has good corrosion resistance and can withstand the low temperatures and high pressures associated with handling liquid oxygen. Stainless steel, copper, titanium, and aluminum may not have the necessary properties to safely handle liquid oxygen, making bronze the correct choice.
43.
(814) When using a water-soluble cleaning agent from components, the first step is to
Correct Answer
A. Flush with large quantities of distilled water.
Explanation
The correct answer is to flush with large quantities of distilled water. When using a water-soluble cleaning agent, the first step is to flush the components with distilled water. This is done to remove any contaminants or residues from the surface of the components. Flushing with distilled water helps to ensure that the cleaning agent can effectively dissolve and remove any dirt or grime present on the components. It is an important step in the cleaning process to ensure that the components are properly cleaned before proceeding with further drying or inspection steps.
44.
(814) Once you clean a TMU27/M liquid oxygen storage and servicing cart component, the next
step is to
Correct Answer
A. Inspect the area with a bright light.
Explanation
After cleaning a TMU-27/M liquid oxygen storage and servicing cart component, the next step is to inspect the area with a bright light. This is important to ensure that the component is completely clean and free from any debris, contaminants, or damage. Inspecting with a bright light helps to identify any potential issues or areas that may need further cleaning or maintenance before the component can be used again. It allows for a thorough examination of the component to ensure its proper functioning and safety.
45.
(814) You find evidence of oil while using the “ultraviolet light method” of cleaning inspections
on the TMU27/M liquid oxygen storage and servicing cart. What action must you take?
Correct Answer
C. Reject the part and clean again.
Explanation
If evidence of oil is found while using the "ultraviolet light method" of cleaning inspections on the TMU-27/M liquid oxygen storage and servicing cart, the appropriate action to take is to reject the part and clean it again. This is necessary to ensure that the cart is free from any oil contamination, which is important for the safe storage and servicing of liquid oxygen. Wiping the oil off may not be sufficient to remove all traces of contamination, and putting the part in the scrap metal bin would be unnecessary if it can be properly cleaned.
46.
(815) You are purging a liquid oxygen (LOX) storage and transfer cart. The purge is considered
complete when the temperature of the air exiting the fill and drain outlet has been maintained at
this temperature for 1 hour.
Correct Answer
A. 220 degrees Fahrenheit (°F).
Explanation
The correct answer is 220 degrees Fahrenheit (°F). This temperature is considered the threshold for completing the purge of a liquid oxygen (LOX) storage and transfer cart. The air exiting the fill and drain outlet needs to be maintained at this temperature for 1 hour to ensure the complete purge.
47.
(815) After purging a liquid oxygen (LOX) storage and transfer cart, the next step is to
Correct Answer
B. Continue to allow the unit to cool the cryotainer to 150°F.
48.
(816) While performing evacuation procedures on a liquid oxygen (LOX) storage and transfer
tank, you find that the vacuum on a cryotainer is too high. What action should you take?
Correct Answer
B. Vacuum down the annular space on the tank.
Explanation
When performing evacuation procedures on a liquid oxygen (LOX) storage and transfer tank, if the vacuum on a cryotainer is too high, the appropriate action to take is to vacuum down the annular space on the tank. This means reducing the vacuum pressure in the space between the inner and outer walls of the tank. By doing so, the excessive vacuum can be corrected, ensuring proper functioning and safety of the tank.
49.
(817) While troubleshooting an aircraft liquid oxygen (LOX) storage and transfer tank, you find
the safety disc blows out below pressure setting that is caused by a defective pop safety valve.
You then take this action with the valve.
Correct Answer
C. Replace.
Explanation
The correct action to take with the defective pop safety valve is to replace it. This is because the safety disc blew out below the pressure setting, indicating that the valve is not functioning properly and cannot effectively regulate the pressure in the LOX storage and transfer tank. By replacing the valve, you can ensure the safe and proper operation of the system.
50.
(817) While transferring liquid oxygen (LOX) from a TMU27/M servicing trailer to an aircraft
oxygen converter, you notice the rate of transfer is very slow. You then troubleshoot by looking
for
Correct Answer
B. Low tank pressure.
Explanation
The correct answer is low tank pressure. When transferring liquid oxygen (LOX) from a TMU-27/M servicing trailer to an aircraft oxygen converter, a slow rate of transfer can indicate that the tank pressure is too low. Low tank pressure can impede the flow of the liquid oxygen, resulting in a slower transfer rate. To resolve the issue, the tank pressure needs to be increased.