2A651 Edition 2 Vol.3 Ure

JP-8 fuel is a type of jet fuel commonly used by the military. It is a mixture of gasoline and kerosene. This combination allows the fuel to have a higher flash point and better performance in cold temperatures compared to regular gasoline. Additionally, the kerosene component provides a higher energy density, making it suitable for use in jet engines.

The purpose of a fuel/oil cooler in a fuel system is to regulate the temperature of both the fuel and the oil. It heats the fuel to a desired temperature and cools the oil to prevent it from overheating. This helps to optimize the performance and efficiency of the fuel system by ensuring that the fuel is at the right temperature for combustion and the oil is kept cool to prevent degradation.

Labyrinth seals are constructed with soft metal, which makes them vulnerable to damage. This is why extreme care is needed when working with them. The soft metal construction of these seals increases the risk of them being easily damaged.

The main fuel control is responsible for regulating the fuel flow to the jet engine. By properly controlling the fuel flow, it ensures that the engine operates within safe parameters and prevents flameout. Flameout refers to the sudden extinguishing of the flame in the combustion chamber, which can occur if the fuel supply is not properly maintained. Therefore, the main fuel control plays a crucial role in preventing flameout and ensuring the safe acceleration of the jet engine.

A gerotor oil pump consists of a gear and rotor within a housing. This type of pump uses the interaction between the gear and rotor to create a pumping action, drawing in and pushing out oil. The gear and rotor have specially shaped lobes that allow for smooth movement and efficient oil flow. Gerotor pumps are commonly used in automotive engines and other machinery that require a reliable and efficient oil circulation system.

Electrohydromechanical fuel control uses various components such as thermocouples, relays, amplifiers, and solenoids to regulate and control the fuel flow in a jet engine. These components work together to monitor and adjust the fuel mixture based on various factors such as temperature, pressure, and engine performance. This type of fuel control system combines electrical, hydraulic, and mechanical elements to ensure efficient and precise fuel delivery, resulting in optimal engine performance.

In the primary mode, the operation of the F100-PW-220 engine is controlled by the DEEC.

Electromagnetic induction is the correct answer because it refers to the process of generating voltage in a conductor when it moves through a magnetic field. This phenomenon was discovered by Michael Faraday in the 19th century and is the basis for the operation of generators and transformers. It is a fundamental concept in electromagnetism and plays a crucial role in various electrical devices and systems.

The T-56 engine fuel nozzle requires a spray pattern inspection in addition to the visual inspection. This means that apart from visually inspecting the nozzle, it is also necessary to check the pattern of the fuel spray it produces. This is important to ensure that the fuel is being distributed evenly and properly for efficient combustion and engine performance.

Calibration and/or adjustment screws that require setting during an engine trim procedure must be safety sealed and/or lockwired. This is because safety sealing and lockwiring ensure that the screws remain in their set position and prevent any unintended adjustments or tampering. By using safety seals and lockwires, the screws are secured and cannot be easily moved or altered, ensuring the accuracy and reliability of the engine trim procedure.

If the results of the laboratory sample are normal, it means that there are no abnormalities or issues with the oil being tested. In such cases, there may not be a need to receive a laboratory sample report as everything is functioning as expected.

A labyrinth oil seal is made of soft metal and allows a small amount of airflow to prevent oil seepage. This type of seal has a complex design with multiple grooves and barriers that create a tortuous path for the oil, preventing it from leaking out. The soft metal composition allows for flexibility and a better seal against the rotating shaft.

Jet aircraft operating at moderately high altitudes increase the fuel system's susceptibility to an icing condition. This is because at higher altitudes, the air temperature is colder, which can cause moisture in the fuel system to freeze and form ice. The viscosity of a liquid refers to its resistance to flow. Jet fuels have a lower viscosity, meaning they flow more easily, compared to free water. Therefore, the lower viscosity of jet fuels can make it easier for ice to form and accumulate in the fuel system, increasing the risk of icing.

The correct answer is corrosiveness. Modern jet engine oil can be corrosive, meaning it has the ability to cause damage or deterioration to metal surfaces it comes into contact with. This is an important property for a journeyman to be aware of, as it can affect the maintenance and safety of the engine.

The discharge air used for aircraft engine anti-icing to heat-critical areas is taken from the compressor. The compressor is responsible for compressing the incoming air and supplying it to the combustion chamber. By using the discharge air from the compressor, which is already at a high temperature, it can be directed to heat-critical areas to prevent ice formation and ensure proper functioning of the aircraft engine.

When a fuel filter is clogged, a differential pressure indicator is actuated. This means that there is a mechanism in the fuel filter that detects the pressure difference between the input and output sides of the filter. When the pressure difference exceeds a certain threshold, the indicator is triggered, indicating that the filter is clogged and needs to be replaced. This allows for easy visual inspection without the need to disassemble the filter.

Microscopic metallic particles in the oil system are called wear metals. These particles are generated as a result of friction and wear between moving parts in the system. They are small enough to be suspended in the oil and can cause damage to the system if not properly managed. Regular oil analysis is conducted to monitor the levels of wear metals and detect any potential issues or abnormalities in the system.

Before taking an oil sample from a drain, it is necessary to drain off water and sludge. This is important because water and sludge can contaminate the oil sample and affect the accuracy of the analysis. By draining off water and sludge, the oil sample will be more representative of the actual condition of the oil, allowing for a more accurate assessment of its quality and any potential issues.

The correct answer is "Brushes." In a simple AC generator, the brushes are responsible for taking the current from the slip rings to operate the electrical device. The brushes make contact with the slip rings, which are connected to the rotating loop of wire in the generator. As the loop rotates, the brushes maintain contact with the slip rings, allowing the current to flow from the generator to the electrical device. The commutator is used in DC generators, not AC generators, to change the direction of the current. The rotating loop and permanent magnet are components of the generator but do not directly take the current to operate the electrical device.

The T56 engine contains 2 gear fuel pumps and 1 boost fuel pump in the fuel pump and filter assembly.

When an augmentor (afterburner) is not operating, its basic function is to act as the basic engine tailpipe. This means that it serves as the outlet for the exhaust gases produced by the engine. The augmentor does not have any additional functions or controls when it is not in use.

A deaerator is a device used to remove air and other dissolved gases from the oil in an engine oil tank. It works by heating the oil and then passing it through a series of trays or baffles, where the air is separated and vented out. This helps to prevent air pockets or bubbles from forming in the oil, which can cause damage to the engine and reduce its efficiency. Therefore, a deaerator is the correct device for separating air from the oil in an engine oil tank.

The air/oil coolers on an F100-PW-220 engine are mounted on the fan duct and use secondary fan airflow as a coolant. This means that the coolers are positioned in such a way that they receive the airflow generated by the secondary fan, which helps to cool the oil in the engine. This is an important function as it helps to regulate the temperature of the oil, ensuring that it does not become too hot and cause damage to the engine components.

The commutator is a part of a generator that acts as an automatic switching device. It is responsible for converting the alternating current produced by the generator into direct current. The commutator consists of a set of copper segments that are connected to the ends of the armature coil. As the armature rotates, the brushes make contact with different segments of the commutator, allowing the current to flow in the desired direction. This switching action ensures that the generated current is always direct current.

An air oil cooler operates on the same principle as a radiator in an automobile. Both the radiator and the air oil cooler use air to cool down the fluid passing through them. In the case of a radiator, air is used to cool down the engine coolant, while in an air oil cooler, air is used to cool down the oil. The air oil cooler consists of fins that help in dissipating heat from the oil as it passes through the cooler, similar to how the radiator fins help in cooling down the engine coolant.

A unified fuel metering device refers to a jet engine component that combines two separate fuel controls into one. This means that instead of having two separate controls for fuel metering, a unified device integrates both controls into a single unit. This helps to simplify the fuel system and improve efficiency by reducing the number of components needed.

At room temperature, it will take water four times longer to settle out of JP-8 than out of gasoline.

The SEM/EDX analysis process requires the particles to be oil free in order to obtain accurate results. This is because the analysis is focused on examining the composition and elemental makeup of the particles, which can be affected or obscured by the presence of oil. Therefore, it is necessary to ensure that the particles are free from oil before conducting the analysis.

The DEEC (Digital Electronic Engine Control) on an F100-PW-220 engine is cooled by fuel. This means that fuel is used to regulate the temperature of the DEEC, preventing it from overheating. The fuel flows through the DEEC, absorbing heat and carrying it away, thus keeping the electronic control system at a safe operating temperature. This cooling mechanism ensures the proper functioning and longevity of the DEEC in the engine.

When an engine is not operating, the static preload for a carbon oil seal is provided by spring pressure. This means that the spring exerts a force on the oil seal, ensuring that it remains in contact with the shaft and prevents any leakage of oil. The spring pressure helps to maintain a tight seal even when there is no oil or hydraulic pressure present.

The P&D valve controls the pressurization of the core engine fuel system. It regulates the flow of fuel to maintain the desired fuel pressure in the core. The fuel nozzle, N2 sensor, and Tt 2.5 sensor are not directly responsible for controlling the pressurization of the core engine fuel system.

The augmenter fuel pump on an F100-PW-220 engine is driven by the 13th stage of compressor air.

The correct answer is gearbox. The breather pressurizing valve on an F100 engine is internally mounted in the gearbox. This valve helps to maintain the proper pressure within the gearbox by regulating the flow of air. It prevents the gearbox from becoming over-pressurized, which can cause damage to the system. By being internally mounted, the valve is able to effectively control the pressure within the gearbox and ensure optimal performance of the engine.

The correct answer is "design pressure differential has been exceeded." This means that the pressure difference between the inlet and outlet of the oil filter has exceeded the maximum limit set by the design. When this happens, the red button on the engine oil filter pops out and remains extended, indicating that there is a problem with the pressure in the filter. This is a safety feature to alert the operator that the filter needs attention and should be replaced.

Jet engine thrust reversers are used to direct engine thrust in the opposite direction. This is typically done during landing to help slow down the aircraft by redirecting the engine's exhaust flow forward. By creating a reverse thrust, the aircraft's forward momentum is reduced, allowing for shorter landing distances and improved braking efficiency. This helps to enhance the safety and control of the aircraft during landing operations.

The correct answer is the Filter assembly bypass valve. During cold weather starts, the oil filter can become clogged or restricted, which can cause a decrease in oil pressure. The filter assembly bypass valve allows oil to bypass the filter and flow directly to the engine, ensuring that there is sufficient lubrication even if the filter is not fully functional.

The correct answer is fan inlet guide vane flaps. On an F110-GE-129 engine, the anti-icing system is responsible for preventing the detrimental formation and accumulation of ice on various parts. In this case, it specifically prevents ice from forming on the fan inlet guide vane flaps. These flaps are located at the front of the engine and play a crucial role in directing the airflow into the engine. It is important to keep them ice-free to ensure proper engine performance and prevent any potential damage caused by ice buildup.

The C-D supersonic inlet uses Bernoulli's law to slow down the airflow. According to Bernoulli's principle, as the speed of a fluid increases, its pressure decreases. In the case of the C-D supersonic inlet, the airflow is slowed down by increasing its pressure. This is achieved by using a converging-diverging nozzle design, which causes the airflow to accelerate initially and then decelerate, resulting in a decrease in velocity and an increase in pressure.

The temperature datum system static check must be made whenever the power section component has been replaced.

The turbine plenum is the engine section that houses the JFS (Jet Fuel Starter) combustion section. The JFS is responsible for providing the initial rotation to start the engine. The turbine plenum is a part of the engine where the combustion gases from the JFS are directed and controlled before entering the main turbine section. It helps to regulate the flow of gases and ensure efficient combustion and power generation in the engine.

The AE2100D3 oil tank pendulum is designed to supply pressurized oil for a minimum of 10 seconds during negative G conditions. This means that even under extreme conditions, the oil tank pendulum is capable of providing a continuous supply of pressurized oil for at least 10 seconds, ensuring the proper functioning of the system during negative G maneuvers.

The primary benefit of identifying an impending failure through the OAP is improved safety. By detecting potential failures before they occur, proactive measures can be taken to prevent accidents or incidents that could compromise the safety of personnel or equipment. This allows for timely repairs or replacements to be made, reducing the risk of catastrophic failures and ensuring a safer working environment.

After the cooling airflow has cooled the turbine section, it is directed into the gas stream to exit the engine. This is because the cooling airflow has already served its purpose of cooling the turbine section and is no longer needed. By directing it into the gas stream, it can be expelled from the engine along with the exhaust gases. This ensures that the cooling airflow does not interfere with the operation of the engine and allows for efficient functioning of the turbine section.

A dry sump oil system stores the oil in a separate tank that is mounted to the side of the engine. This design allows for better lubrication and cooling of the engine, as the oil is not stored in the engine's crankcase like in a wet sump system. The separate tank also prevents oil starvation during high-speed or high-g cornering situations, as it can provide a constant supply of oil to the engine. Therefore, the correct answer is dry sump.

Chip detectors have an electrical connection for making a continuity check. This means that they are used to check if there is a continuous electrical path between two points in a circuit. In the context of chip detectors, this check is important to ensure that the electrical connection between the chip detector and the system it is monitoring is intact. By confirming continuity, the chip detector can effectively detect any potential issues or abnormalities in the system.

A hot tank oil system design places the oil cooler in the pressure subsystem. This means that the oil cooler is located in a part of the system where the oil is under pressure. The purpose of the oil cooler is to cool the oil and prevent it from overheating. By placing it in the pressure subsystem, the cooler can effectively remove heat from the oil as it flows through the system under pressure. This design helps to maintain the oil at the proper temperature and prevent any damage or degradation that could occur from excessive heat.

When the null orifice on the T56 engine TD valve is set at zero, it means that the valve is completely closed. In this position, no fuel will bypass the valve, resulting in a bypass percentage of 0%. Therefore, the correct answer is 0%.

The T56 engine speed-sensitive control allows electrical current to flow to the fuel and ignition system at 16% RPM. This means that when the engine is running at 16% of its maximum RPM, the control system will activate and allow the necessary electrical current to power the fuel and ignition system. This control helps to ensure that the engine functions properly and efficiently at different RPM levels.

The TD amplifier on the T56 engine compares the desired throttle setting from the coordinator with the actual TIT (turbine inlet temperature) signal from the thermocouples. It is responsible for regulating the fuel flow to maintain the desired TIT level. The TD valve, speed-sensitive control, and TD potentiometers are not directly involved in this comparison process.

The correct answer is transformer because a transformer is a device that can increase or decrease the voltage of an alternating current (AC) electrical signal. In an AC ignition system, the transformer is responsible for stepping up the voltage from the battery to a much higher voltage, typically around 20,000 volts, which is necessary to create a spark in the spark plugs and ignite the fuel-air mixture in the engine.