2A651 CDC 3 (2013)

JP-8 fuel is a type of jet fuel used by the United States military. It is a combination of gasoline and kerosene. This composition provides the fuel with the necessary properties for use in jet engines, including high energy content and low freezing point. Gasoline provides high energy density while kerosene has a lower freezing point and better lubricating properties. This combination allows JP-8 fuel to be used in a wide range of temperatures and provides optimal performance for military aircraft.

Electrohydromechanical fuel control uses various components such as thermocouples, relays, amplifiers, and solenoids to regulate the fuel flow in a jet engine. This type of control system combines electrical and hydraulic mechanisms to ensure precise control over the fuel delivery, optimizing engine performance and efficiency.

In the primary mode, the operation of the F100-PW-220 engine is controlled by the DEEC (Digital Electronic Engine Control). The DEEC is responsible for monitoring and adjusting various engine parameters such as fuel flow, temperature, and pressure to ensure optimal performance and efficiency. It receives inputs from various sensors and uses algorithms to make real-time adjustments to maintain the desired engine operation.

During an engine trim procedure, calibration and/or adjustment screws may need to be set to ensure the engine operates optimally. To prevent any unauthorized tampering or accidental adjustments, these screws should be safety sealed and/or lockwired. This ensures that they cannot be easily moved or altered once they have been properly set. This practice helps maintain the accuracy and reliability of the engine trim procedure.

The augmentor, also known as an afterburner, acts as the basic engine tailpipe when it is not operating. This means that when the afterburner is not in use, it functions as a regular tailpipe for the engine, allowing the exhaust gases to exit the engine. The afterburner is only activated when additional thrust is required, such as during takeoff or during high-speed maneuvers. In normal operating conditions, the afterburner remains inactive and serves as a regular tailpipe.

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 machinery. Over time, these wear metals can cause damage to the components and reduce the efficiency of the system. Regular monitoring and analysis of wear metals in the oil system is crucial for preventive maintenance and to ensure the proper functioning of the machinery.

Electromagnetic induction is the term for the process of producing voltage in a conductor when it passes through a magnetic field. This phenomenon was discovered by Michael Faraday in the early 19th century and is the basis for the operation of generators and transformers. It occurs when there is a relative motion between a conductor and a magnetic field, resulting in the generation of an electromotive force (EMF) or voltage. This process is fundamental to the functioning of many electrical devices and plays a crucial role in the field of electromagnetism.

The turbine plenum is the engine section that houses the JFS (Jet Fuel Starter) combustion section. The JFS is responsible for starting the engine and providing additional power during certain flight phases. The turbine plenum is located between the compressor section and the turbine section of the engine, and it is where the combustion process takes place.

The main fuel control in a jet engine is responsible for regulating the amount of fuel being supplied to the engine. By controlling the fuel flow, it ensures that the engine operates within safe parameters and prevents a flameout, which is the sudden extinguishing of the flame in the combustion chamber. This is crucial for the safe acceleration and continuous operation of the engine. A flameout can occur due to various reasons such as insufficient fuel supply, excessive airflow, or a malfunctioning fuel control system. Therefore, the main fuel control plays a vital role in reducing the possibility of a flameout.

Labyrinth seals are made of soft metal, which makes them prone to damage. This is why extreme care should be taken when working with them.

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 designed to utilize the airflow generated by the secondary fan to cool down the air and oil in the engine. This helps in maintaining the temperature of the engine components within the desired range and prevents overheating.

If the results of the laboratory sample are normal, it means that there are no abnormalities or issues detected in the sample. In such cases, there may not be a need to receive a report as everything is functioning as expected. The laboratory sample reports are typically provided to highlight any potential problems or abnormalities in the sample, so if the results are normal, there may not be a need for a report.

The DEEC (Digital Electronic Engine Control) on an F100-PW-220 engine is cooled by fuel. The DEEC is responsible for monitoring and controlling various engine parameters. Cooling the DEEC with fuel ensures that it operates at an optimal temperature and prevents overheating. This cooling method is effective and efficient as fuel is readily available and circulated throughout the engine during operation.

The correct answer is fan inlet guide vane flaps. On an F110-GE-129 engine, the anti-icing system is designed to prevent the formation and accumulation of ice on various components, including the front frame struts, forward centerbody, and ring cowl. However, the fan inlet guide vane flaps are specifically responsible for preventing ice formation and accumulation in the fan inlet area. These flaps help to ensure that the engine receives a sufficient amount of air for proper operation by preventing ice blockages in the fan inlet.

The purpose of a fuel/oil cooler in a fuel system is to heat the fuel and cool the oil. This is because fuel needs to be heated in order to vaporize and combust efficiently, while oil needs to be cooled to prevent it from overheating and losing its lubricating properties. By heating the fuel and cooling the oil, the fuel/oil cooler ensures optimal performance and longevity of the fuel system components.

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

After the cooling airflow has cooled the turbine section, it is directed into the gas stream to exit the engine. This is because the purpose of the cooling airflow is to absorb the excess heat generated by the turbine and prevent any damage to the engine components. By directing the cooling airflow into the gas stream, it is efficiently expelled from the engine along with the exhaust gases, ensuring that the engine operates at optimal temperatures and performance levels.

A gerotor oil pump consists of a gear and rotor within a housing. The gear rotates inside the rotor, creating chambers that draw in and push out oil. This design allows for efficient and reliable oil pumping, making gerotor pumps commonly used in various applications, including automotive engines.

When an engine is not operating, static preload for a carbon oil seal is provided by spring pressure. This means that the carbon oil seal is compressed and held in place by a spring, creating a seal that prevents oil from leaking out. Air pressure, oil pressure, and hydraulic pressure are not typically used to provide static preload for a carbon oil seal in an engine.

A unified fuel metering device in a jet engine refers to a component that combines two fuel controls into one. This means that it performs the functions of two separate fuel controls, making it more efficient and streamlined. The term "unified" accurately describes this type of fuel metering device.

At room temperature, water will take four times longer to settle out of JP-8 than out of gasoline. This implies that JP-8 has a higher density or viscosity compared to gasoline, which slows down the settling process of water.

The turbine plenum on the JFS provides pads for mounting the fuel atomizer assembly. The fuel atomizer assembly is responsible for injecting fuel into the combustion chamber, and it needs to be securely mounted in order to function properly. The stator ring, exhaust housing, and generator assembly do not have this specific function of providing pads for mounting the fuel atomizer assembly.

In an F100-PW-220 engine, the augmenter fuel pump is driven by the 13th stage of compressor air. This means that the 13th stage of the compressor provides the necessary power to drive the augmenter fuel pump, which is responsible for delivering fuel to the afterburner. The other stages mentioned in the options (7th, 10th, and 14th) do not play a role in driving the augmenter fuel pump.

A differential pressure indicator is actuated when a fuel filter is clogged. This means that there is a pressure difference between the inlet and outlet of the filter, indicating that the flow of fuel is being restricted. This is a visual indication that the filter is clogged and needs to be replaced.

A deaerator is a device used in an engine oil tank to separate air from the oil. It works by removing dissolved gases such as oxygen and carbon dioxide from the oil, preventing oxidation and corrosion. This helps to maintain the oil's quality and prolong the life of the engine. Aerator, check valve, and bypass valve do not perform the function of separating air from the oil, making them incorrect choices.

An air oil cooler operates on the same principle as a radiator in an automobile. Both the air oil cooler and radiator use the process of heat exchange to cool down the fluid passing through them. In the case of an air oil cooler, the hot oil flows through the cooler's tubes, and air is blown over the tubes to dissipate the heat. This is similar to how a radiator in an automobile uses air to cool down the engine coolant. Therefore, the correct answer is air.

A labyrinth oil seal is made of soft metal and allows a small amount of airflow to prevent oil seepage. This type of seal is designed with a complex maze-like structure that creates a tortuous path for the oil to flow through, effectively sealing off any potential leakage. The soft metal composition allows for flexibility and durability, ensuring a reliable and long-lasting seal. Silicone, carbon, and synthetic oil seals do not possess the same airflow characteristics and are not specifically designed to prevent oil seepage.

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 to high pressure before it enters the combustion chamber. This compressed air is then used for various purposes, including anti-icing to prevent ice formation on critical areas of the engine.

The PTO shaft that is used to drive the CSD (Constant Speed Drive) is provided by the engine adapter. The engine adapter connects the engine to the CSD and allows the power to be transferred from the engine to the CSD through the PTO shaft. This ensures that the CSD receives the necessary power to operate efficiently.

The slide-type resistor in the EGT circuit is used to calibrate the EGT indicator in the flight station. This means that the resistor is used to adjust the EGT indicator so that it accurately displays the temperature readings from the thermocouples. By calibrating the indicator, any inaccuracies or discrepancies in the temperature measurements can be corrected, ensuring that the EGT readings are reliable and precise.

Jet engine thrust reversers are used to direct the engine thrust in the opposite direction, which helps in slowing down the aircraft during landing and providing additional braking force. By redirecting the exhaust gases forward, the thrust reversers create a reverse thrust that counteracts the forward motion of the aircraft, allowing it to decelerate more effectively. This helps in reducing the landing distance and improves the overall safety of the aircraft during landing operations.

The correct answer is 2 gear; 1 boost. This means that there are two gear fuel pumps and one boost fuel pump contained in the fuel pump and filter assembly of the T56 engine.

The fuel/oil cooler is responsible for heating the augmentor fuel to improve its vaporization and combustion. By heating the fuel, it helps to achieve better atomization and mixing with air, leading to more efficient combustion. This component plays a crucial role in optimizing the performance of the fuel system and ensuring that the fuel is properly utilized in the combustion process.

When the red button on an F100-PW-220 engine oil filter pops out and remains extended, it indicates that the design pressure differential has been exceeded. The design pressure differential refers to the maximum pressure difference that the oil filter can handle. If this limit is exceeded, it suggests that there is a problem with the engine or the oil system, and the filter may not be able to effectively filter the oil. Therefore, the extended red button indicates a defective filter due to the exceeded design pressure differential.

The filter assembly bypass valve is the component that permits oil to bypass the oil filter during cold weather starts on an F100-PW-220 engine. This valve allows the oil to flow directly to the engine without going through the filter, ensuring that the engine receives lubrication even if the filter is clogged or the oil is too thick in cold temperatures. It helps to prevent damage to the engine and ensures smooth operation during cold starts.

The primary benefit of identifying an impending failure through the OAP is improved safety. By detecting potential failures before they occur, necessary maintenance or repairs can be carried out, preventing accidents or hazards that could compromise the safety of personnel or equipment. This proactive approach allows for timely interventions and mitigates the risk of accidents, making the overall operation safer.

SEM/EDX analysis is a technique used to determine the elemental composition of particles. In order to accurately analyze the particles, it is necessary for them to be free of any oil contamination. Oil can interfere with the analysis and lead to inaccurate results. Therefore, the particles must be oil free for the SEM/EDX analysis to be conducted successfully.

The JFS (Jet Fuel Starter) uses an annular combustion chamber. An annular combustion chamber is a type of combustion chamber where the fuel and air mixture is ignited in a ring-shaped chamber surrounding the central axis. This design allows for efficient combustion and better control of the combustion process. The annular combustion chamber is commonly used in gas turbine engines, including the JFS, due to its compact size and high performance capabilities.

The correct answer is brushes. In a simple AC generator, the brushes are responsible for taking the current from the slip rings and transferring it to the electrical device. The brushes make direct contact with the slip rings, allowing the current to flow through them and power the device. The commutator is a component found in DC generators, not AC generators. The rotating loop and permanent magnet are not directly involved in transferring the current to the electrical device.

The MFC (Main Fuel Control) on an F100-PW-220 engine is capable of operating in two modes.

The unit of an AC ignition system that develops 20,000 volts is a transformer. A transformer is a device that can increase or decrease the voltage of an alternating current. In this case, it is used to step up the voltage from a lower value to 20,000 volts, which is necessary for the ignition system to generate a spark and ignite the fuel mixture in the engine.

Before taking an oil sample from a drain, it is necessary to drain enough fluid into a container in order to remove any water and sludge that may have accumulated in the oil. This is important because water and sludge can contaminate the oil and affect its performance and lubricating properties. By draining off the water and sludge, the oil sample will be more representative of the actual oil condition and provide accurate information for analysis and maintenance purposes.

The hydraulic motor is the item that initially rotates the JFS (Jet Fuel Starter). This means that it is responsible for starting the rotation of the JFS, which is an important component in the aircraft. The ESS PTO, electric motor mounted on the aircraft, and engine PTO are not mentioned as items that perform this initial rotation function.

The commutator is the part of a generator that acts as an automatic switching device, changing alternating current to direct current. It consists of a series 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 one direction. This conversion from alternating current to direct current is essential for the generator to provide a steady and usable power output.

The correct answer is MFC, fuel/oil cooler, P&D, and fuel nozzles. This is the correct sequence for the core engine fuel flow on an F100-PW-220 engine. The fuel flow starts at the main fuel control (MFC), then goes through the fuel/oil cooler, the primary and drain (P&D) valves, and finally reaches the fuel nozzles.

The correct answer is torch igniter and pilot burner ring. These two types of augmentor ignition systems are used in afterburners. A torch igniter is a device that creates a continuous flame to ignite the fuel-air mixture in the afterburner, while a pilot burner ring is a circular arrangement of smaller burners that provide a stable flame to ignite the main fuel-air mixture. These ignition systems ensure proper combustion and efficient operation of the afterburner.

The T-56 engine fuel nozzle requires a spray pattern inspection in addition to visual inspection. This type of inspection is necessary to ensure that the fuel is being sprayed in the correct pattern and direction for optimal engine performance. By checking the spray pattern, any abnormalities or issues with the fuel nozzle can be identified and addressed, ensuring that the engine operates efficiently and effectively.

Chip detectors have an electrical connection for making a continuity check. This means that the electrical connection is used to check if there is a continuous flow of electrical current through the chip detector. By checking for continuity, it can be determined if the chip detector is functioning properly and if there are any breaks or interruptions in the electrical circuit. This is important because any interruptions in the circuit could indicate a problem or malfunction in the chip detector, which could affect its ability to detect and monitor any metal particles or debris in the system.

The project monitor is responsible for ensuring that the OAP (Optical Airborne Payload) operates properly. As the overseer of the project, the project monitor is tasked with monitoring and overseeing all aspects of the project, including the proper functioning of the OAP. They are responsible for ensuring that the equipment is functioning correctly, coordinating with the team members involved in the project, and addressing any issues or concerns that may arise during the operation of the OAP.

The C-D supersonic inlet uses Bernoulli's law to slow down the airflow. Bernoulli's law states that as the speed of a fluid increases, its pressure decreases. In the case of the supersonic inlet, the high-speed airflow is compressed and slowed down by increasing the pressure, allowing it to enter the engine at a manageable speed. This principle is crucial for the efficient operation of supersonic aircraft engines.