CDC 2A651 Self Test EOC Pre-test

Cracks that appear on the combustion chamber are normally aggravated by thermal cycles. The repeated heating and cooling of the chamber during the combustion process causes expansion and contraction, leading to stress and ultimately crack formation. This phenomenon is known as thermal fatigue, and it is a common cause of damage in high-temperature environments like combustion chambers.

A TCTO (Time Compliance Technical Order) can be quickly identified by the number #501 or higher. This suggests that TCTOs are numbered in a sequential order, and any TCTO with a number higher than 501 would be considered as a quick identifier. It is likely that the numbering system used for TCTOs follows a specific pattern or hierarchy, with #501 or higher indicating a more recent or important TCTO.

The second part of the TO number gives you the model and series for equipment in the TO. This means that by looking at the second part of the TO number, you can determine the specific model and series of the equipment that the TO pertains to.

The overall reduction ratio of the RGB is 13.54 to 1. This means that for every 13.54 units of the original value, there is a reduction to 1 unit. This ratio indicates a significant reduction in the value, suggesting that the RGB has undergone a substantial decrease in magnitude.

The light is transmitted to the tip of a borescope through fiber optics. Fiber optics are thin, flexible strands of glass or plastic that can transmit light over long distances without significant loss of intensity. In a borescope, the fiber optics are typically bundled together and housed within the insertion tube. The light enters the borescope through a light source, travels through the fiber optic bundle, and is then emitted at the tip of the borescope, illuminating the area being inspected. This method allows for efficient and effective transmission of light in a compact and flexible design.

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The torque must reach between -4,200 and -7,200 inch pounds for the safety coupling to disconnect the power unit and RGB.

When abnormal noises are detected during a static blade transition check of the 54-H60-91 propeller, it is necessary to return the propeller to the depot. In order to document this process and accompany the propeller back to the depot, AFTO form 95 must be used.

Turbine blade fatigue failure does not result from blends. Fatigue failure in turbine blades is typically caused by repeated stress cycles, which can be caused by factors such as nicks, dents, and scratches. However, blends, which refer to the smooth transitions between different surfaces on the blade, do not contribute to fatigue failure. Blends are designed to minimize stress concentrations and improve the aerodynamic performance of the blade.

The reason why defects, such as cracks found during combustion chamber inspection, are preferred over a borescope inspection is that you could spot defects that may have been missed by the borescope. This suggests that the borescope may not always provide a comprehensive or accurate view of the combustion chamber, potentially leading to missed defects. Therefore, a direct inspection of the combustion chamber allows for a more thorough examination and identification of any defects that may have been overlooked by the borescope.

The correct answer is Air. An air oil cooler operates on the same principle as a radiator in an automobile. It uses airflow to cool down the oil, just like a car radiator uses airflow to cool down the coolant. This type of oil cooler typically has fins or tubes that allow the oil to come in contact with the air, facilitating the heat transfer process and cooling the oil.

The oil pump check valve prevents oil in the oil tank from draining into the RGB rear case. This valve ensures that the oil flows in the desired direction and prevents any backflow or leakage from occurring. It acts as a barrier to keep the oil within the oil pump and filter system, preventing it from draining into the RGB rear case.

A capacitor is a device that temporarily stores electrical energy. It consists of two conductive plates separated by an insulating material called a dielectric. When a voltage is applied across the plates, positive and negative charges accumulate on each plate, creating an electric field. This electric field stores energy in the form of an electric field. Capacitors are commonly used in electronic circuits to store energy and release it when needed, such as in smoothing out power supply voltages or storing energy for a brief period in flash photography.

The fuel flow indicator is used to measure the rate at which fuel is being consumed by an engine. This rate is typically measured in pounds per hour, as it provides a more accurate measurement of fuel consumption. Pounds per hour takes into account the weight of the fuel being consumed, which can vary depending on factors such as temperature and altitude. Gallons per hour or gallons per second do not account for these variations and may provide less accurate information. Pounds per minute is not commonly used as a unit of measurement for fuel flow.

The correct answer is Radar, electronic countermeasure, and radio equipment. These three types of equipment produce radio frequency radiation. Radar is used for detecting the presence, direction, distance, and speed of aircraft, ships, and other objects. Electronic countermeasure refers to systems used to jam or disrupt enemy radar and communication systems. Radio equipment includes any devices that transmit or receive radio signals, such as radios, transmitters, and antennas. These three types of equipment are commonly used in aviation and can potentially emit radio frequency radiation, which can pose safety hazards if not properly managed.

Kerosene has a heat content of 18,500 Btu's per pound. This means that when one pound of kerosene is burned, it releases 18,500 British Thermal Units (Btu's) of heat energy.

The DEEC (Digital Electronic Engine Control) is the engine component that controls the AFC (Air Fuel Control). It is responsible for regulating the fuel flow and air-fuel mixture in the engine to optimize performance and efficiency. The DEEC uses digital electronic signals to monitor and adjust various engine parameters, ensuring smooth operation and proper combustion.

The purpose of the AFTO IMT 95 is to record significant historical data. This form is used to document important information about an event or maintenance action, such as the date, location, and details of the event. It serves as a record for future reference and analysis, allowing maintenance personnel to track and assess the history of an aircraft or equipment.

Tapered pins are used in joints that carry shear loads and where the absence of clearance is essential. Tapered pins have a gradual decrease in diameter along their length, allowing them to fit tightly into the holes of the joint. This tight fit ensures that the joint remains stable and can withstand shear forces without any movement or play. The absence of clearance is important in these joints to maintain the structural integrity and prevent any unwanted movement or shifting.

Having contamination in the bucket already is important to consider when checking the main oil filter for contamination because it can lead to inaccurate readings. If there is already contamination present in the bucket, it could be mistakenly attributed to the oil filter, giving a false indication of its condition. Therefore, ensuring a clean container is necessary to accurately assess the contamination level of the oil filter.

The compressor section of a jet engine is responsible for producing the large volumes of air required for the production of thrust. It compresses incoming air, increasing its pressure and density before it enters the combustion chamber. This compressed air is then mixed with fuel and ignited, creating a high-pressure and high-temperature gas that is expelled through the turbine section, generating thrust. The compressor plays a crucial role in the overall performance and efficiency of the jet engine.

The correct answer is that the impeller is a forged single unit. This means that the impeller is made from a single piece of material that has been forged, or shaped, into its final form. This constructional feature ensures that the impeller is strong and durable, as there are no joints or seams that could potentially weaken the structure. Additionally, being a single unit helps to improve the overall efficiency and performance of the centrifugal compressor.

The correct answer is after the last flight of the flying period. A post-flight inspection is conducted after the aircraft has completed its final flight of the day. This inspection ensures that any potential issues or damages that may have occurred during the flight are identified and addressed before the next day's operations. It is an essential part of aircraft maintenance and helps to ensure the safety and airworthiness of the aircraft.

The correct answer is 91-1. AFOSH stands for Air Force Occupational Safety and Health, and the series of AFOSH standards that govern occupational safety is 91-1. These standards provide guidelines and regulations to ensure the safety and well-being of workers in the Air Force.

The given question asks which maintenance platform is not adjustable. The answer is C-1. This means that maintenance platform C-1 cannot be adjusted.

The AC ignition system delivers approximately 115 volts to the igniter plug. This high voltage is necessary to create a spark that ignites the fuel-air mixture in the engine's cylinders. It is important for the ignition system to deliver a sufficient amount of voltage to ensure reliable ignition and efficient engine operation.

The barrel assembly retains the blades, attaches the propeller to the engine shaft, and transmits engine torque to the blades.

The correct answer is blade shim plate. The blade shim plate is used in place of the beta segment gear on blades No.2,3, and 4. This component serves to adjust and balance the blades, ensuring proper alignment and performance. It is a crucial part of the blade assembly and helps to maintain the optimal functioning of the blades.

Purple dye is used as a type of special inspection to find minute cracks on a propeller blade. This is because the dye penetrates into the cracks and makes them visible, allowing inspectors to identify and assess any damage or potential issues with the propeller blade. The purple dye method is commonly used in industries such as aviation and manufacturing to ensure the safety and integrity of critical components.

After running an engine in augmentation in the hush house, the augmentor tube is cooled by running the engine at idle for a period of 3 minutes. This is necessary to allow the augmentor tube to cool down and prevent any damage or overheating. Running the engine at idle allows for a slower and controlled cooling process, ensuring that the augmentor tube is properly cooled before it can be safely handled or worked on.

You should check the 781A and 781H forms for entries that may prevent you from starting your assigned task.

The valve in the propeller control assembly that is actuated by the NTS actuator rod to increase propeller blade angle is the Feather valve.

The purpose of the T56 safety coupling is to disconnect the power section from the RGB assembly. This is important in case of any malfunction or emergency situation where it becomes necessary to separate the power section from the rest of the assembly. By disconnecting the power section, potential damage or further issues can be prevented, ensuring the safety of the aircraft and its components.

Complete loss of lubrication is the most common cause of bearing failure. When a bearing loses its lubrication, the friction between the moving parts increases, leading to excessive heat generation and wear. Without lubrication, the bearing surfaces can become damaged, leading to increased friction, overheating, and ultimately, failure. It is important to ensure proper lubrication to prevent bearing failure and maintain optimal performance and longevity of the bearing.

The probable cause of a bearing race rotating on the shaft is an improper bearing install. This means that the bearing was not installed correctly, resulting in the race rotating instead of remaining stationary on the shaft.

The answer 23-110 refers to a specific code or entry in the AF IMT 2005. To understand the meaning or details of this code, one should refer to the AFMAN 23-110 document. This document likely provides information or instructions related to the AF IMT 2005 codes and entries.

The given correct answer is "Two stages of reduction." This implies that in the RGB assembly, there are two stages where the reduction process occurs. This suggests that the assembly goes through a series of steps or stages to reduce the RGB components. However, without further context or information, it is difficult to determine the specific details of these stages or the purpose of the reduction process.

When an engine is not operating, the carbon oil seal requires a static preload to maintain a proper sealing function. This preload is provided by spring pressure. The spring applies a constant force on the seal, ensuring that it remains in contact with the mating surface and prevents any leakage of oil. Air pressure, oil pressure, and hydraulic pressure are not suitable for providing the necessary static preload in this case.

The exhaust nozzle position indicating system found on engines with afterburners is important because it helps the pilot determine engine power. By providing the pilot with information about the position of the exhaust nozzle, the system allows them to monitor and adjust the engine power output accordingly. This is crucial for maintaining optimal performance and ensuring the engine operates within safe limits.

The correct answer is 4 because a linear hydraulic actuator is a type of actuator that converts hydraulic energy into linear motion. In the context of deploying and stowing the fan thrust reverser, it is common to use four linear hydraulic actuators. These actuators are responsible for controlling the movement of the thrust reverser, allowing it to be deployed during landing and stowed during normal operation.

The given answer correctly states Newton's first law of motion, also known as the law of inertia. This law states that an object at rest will remain at rest, and an object in motion will continue moving at a constant speed in a straight line, unless acted upon by an external force. This law highlights the concept of inertia, which is the tendency of an object to resist changes in its motion.

Newton's second law of motion states that an unbalanced force acting on an object will cause the object to accelerate in the direction of the force. The acceleration of the object is directly proportional to the force applied and inversely proportional to the mass of the object. In other words, the greater the force applied to an object, the greater the acceleration, and the smaller the mass of the object, the greater the acceleration for a given force.

The RGB (Red, Green, Blue) is a color model used in digital imaging. In this context, the question is asking about the number of scavenge oil pumps located in the RGB. The correct answer is 2, although the question does not provide any further information about the purpose or function of these pumps. It is assumed that in the RGB system, there are two scavenge oil pumps responsible for a specific task or process.

The forward end of the shaft on a centrifugal compressor is hollow in order to provide a passage for the main fuel supply. This allows the fuel to be delivered to the combustion chamber where it can be ignited to produce the necessary power for the compressor. Without this hollow passage, the fuel would not be able to reach the combustion chamber, rendering the compressor ineffective.

The correct answer is the torquemeter assembly. The torquemeter assembly is connected to the power unit on a T56 engine. The torquemeter measures the torque output of the engine, which is an important parameter for monitoring and controlling engine performance. By connecting the torquemeter assembly to the power unit, the engine's torque can be accurately measured and monitored.

The correct answer is 10%. This means that the oil sampling intervals should not vary more than 10% in order to maintain consistency. This ensures that the intervals are not too frequent or too infrequent, allowing for accurate and reliable analysis of the oil's condition. A 10% variation provides a balance between timely monitoring and cost-effectiveness.

The T56 speed sensitive control de-energizes the ignition exciter at 65%. This means that when the T56 engine reaches a certain speed, the ignition exciter is no longer powered. This could be a safety mechanism to prevent the engine from overheating or to conserve energy.

The correct answer is "ground start." In aircraft engines like the T56, the ground start switch is responsible for energizing the starter control valve, which then moves to the OPEN position. This allows for the initiation of the engine start sequence. The ground start switch is specifically designed for starting the engine while on the ground, and it plays a crucial role in the overall start-up process.

The impeller on the f100 engine is driven by the 13th stage air.

The correct answer is "compositer" because in early ignition systems, the voltage is stepped up by using a device called a compositer. This device helps to increase the voltage from the battery to a level that is suitable for igniting the fuel-air mixture in the engine. The compositer is an essential component in the ignition system as it ensures that the spark generated by the igniter plug is strong enough to ignite the fuel and start the combustion process.

The two types of thrust reversers are aerodynamic blockage and mechanical blockage. Aerodynamic blockage reversers redirect the exhaust gases by blocking the normal flow of the exhaust, while mechanical blockage reversers physically redirect the exhaust flow by using doors or other mechanical devices.

The correct answer is 4 because the question asks about the number of linear hydraulic actuators used to deploy and stow the fan thrust on the F117-PW-100 engine. The answer 4 indicates that there are four linear hydraulic actuators involved in this process.

The correct answer is cracks, burns, erosion, and missing coating. During combustion section inspections, these are the four types of defects that are typically found on a combustion liner. Cracks can occur due to thermal stress or fatigue, burns can be caused by high temperatures or flame impingement, erosion can happen due to the abrasive effect of combustion gases, and missing coating can result from wear and tear or corrosion. These defects need to be identified and addressed to ensure the safe and efficient operation of the combustion system.

The T56 compressor rotor is supported by roller bearings at the front and ball bearings at the rear. Roller bearings are typically used in applications where there is a need for high radial load capacity, while ball bearings are used when there is a need for high-speed and low-friction operation. Therefore, the front roller bearing provides the necessary radial support for the compressor rotor, while the rear ball bearing allows for smooth and efficient rotation.

The starter control valve functions as an on-off control for the air supply that is sent to the starter. It regulates the flow of air to the starter, allowing it to start and stop as needed. This valve is an important component in the T56 engine, as it ensures that the starter receives the necessary air supply to initiate the engine start-up process.

The overheat detector unit used on aircraft engines consists of a hollow stainless steel tube that covers two silver contacts. This design allows the contacts to be protected from the high temperatures generated by the engine. When the temperature exceeds a certain threshold, the contacts expand and make contact, indicating an overheat condition. The use of silver contacts ensures good conductivity and reliability in detecting overheat situations.

Corrosion pitting can be caused by various factors such as moisture, lack of protective oils, improper handling, or improper storage. When bearings are exposed to moisture or corrosive environments, the metal surfaces can deteriorate, leading to localized corrosion and the formation of pits. These pits can weaken the bearing and eventually lead to its failure. Therefore, corrosion pitting is a possible consequence of the mentioned factors.

If you are assigned to a specialist flight in the aircraft maintenance squadron, you may be required to accomplish Isochronal/Phase Inspection tasks. This type of inspection involves a thorough examination of the aircraft's systems and components at regular intervals, usually every 400-600 flight hours. It includes checking and testing various systems, replacing worn-out parts, and ensuring that the aircraft is in compliance with maintenance and safety standards. This inspection is crucial for identifying and addressing any potential issues or defects in the aircraft to ensure its continued airworthiness and safe operation.

DD Form 1575 is the correct answer because it is the form that is attached to items that are awaiting maintenance. This form is used to track and document the status of items that are in need of maintenance or repair. It provides information such as the item's identification, condition, and the reason it requires maintenance. By using this form, the maintenance personnel can easily keep track of the items that are awaiting maintenance and ensure that they are addressed in a timely manner.

A flathead pin is used in conjunction with a cotter pin. A flathead pin has a flat, broad head that provides a larger surface area for the cotter pin to secure against. This design helps to prevent the cotter pin from slipping out of place and ensures a more secure connection.

Cover plate seals are used to retain the turbine buckets in the 1st stage wheel of the T56-A-15 engine. Cotter pins are used to secure bolts or pins, curvic splines are used to transmit torque, and anti-rotation pins are used to prevent rotation. However, none of these options are specifically used to retain turbine buckets in the 1st stage wheel.

The correct answer is "Two concentric shafts, torquemeter housing, and a torquemeter pickup." This is because a torquemeter assembly typically consists of two concentric shafts, which allow for the measurement of torque, a torquemeter housing that encloses the assembly, and a torquemeter pickup that detects the torque being applied. The other options do not accurately describe the components of a torquemeter assembly.

Jet fuels tend to ice up at higher altitudes due to the combination of extremely low temperatures and higher viscosity. At higher altitudes, temperatures can drop significantly, causing the fuel to reach extremely low temperatures. As the temperature decreases, the viscosity of the fuel increases, making it thicker and more prone to forming ice crystals. This can potentially clog fuel lines and filters, leading to engine failure.

A filler cap with a graduated gauge is used to check the oil level in a F108 engine. This means that the cap on the oil tank has a gauge on it, which allows the user to visually measure the oil level in the engine. By using this graduated gauge on the filler cap, the operator can ensure that the engine has the correct amount of oil for optimal performance.

The flap actuator regulates the amount of ram air passing through the oil cooler core. It controls the opening and closing of the flap, which in turn adjusts the airflow. By adjusting the flap position, the flap actuator can increase or decrease the amount of air passing through the oil cooler core, helping to regulate the temperature of the oil and prevent overheating.

The hydraulic motor is the item that initially rotates the JFS (Jet Fuel Starter). This motor is responsible for providing the initial rotational force to start the JFS, which in turn helps to start the aircraft's engine.

A fuel flow transmitter is a fuel system component of a jet engine that operates by using a water wheel concept. It measures the rate at which fuel is flowing through the engine and transmits this information to the fuel flow indicator. The water wheel concept refers to the mechanism inside the transmitter that rotates in response to the flow of fuel, similar to how a water wheel rotates when water flows through it. This rotation is then converted into electrical signals that are used to display the fuel flow rate on the fuel flow indicator.

The correct answer is 16. This means that there are 16 fuel nozzles installed on the AE2100D3 engine diffuser.

When the turbine nozzles are burned out unevenly around the annulus due to an overtemperature condition, it is known as a severe stall with disrupted cooling airflow. This means that the airflow necessary for cooling the turbine nozzles is interrupted, leading to severe stalling.

The energy that is absorbed by the turbine section used to drive on a T56 engine is provided by the compressor rotor, engine accessories, RGB assembly, and propeller. These components work together to convert the high-pressure air generated by the compressor into rotational energy, which is then transmitted to the propeller to produce thrust. The compressor rotor compresses the incoming air, the engine accessories help with the overall operation of the engine, the RGB assembly transfers the rotational energy to the propeller, and the propeller converts this energy into thrust for the aircraft.

The OSG on the cartridge pneumatic starter consists of flyweights and piston. The flyweights are responsible for controlling the speed of the starter and adjusting it based on the load. The piston, on the other hand, is responsible for compressing the air in the cartridge, which then creates the necessary force to start the engine.

Pitchlock occurs between blade angles of 25 degrees and 55 degrees.

The potentiometer in the T56 engine coordinator provides reference signals to the electronic TD amplifier that are proportional to the desired TIT. A potentiometer is a variable resistor that can be adjusted to control the output voltage. In this case, it is used to provide a signal that corresponds to the desired turbine inlet temperature (TIT). The electronic TD amplifier then uses this signal to adjust the engine parameters accordingly. The feather switch, 65 degree microswitch, and 66 degree microswitch are not related to providing reference signals for the desired TIT.

Cams and mechanical linkage move the pilot valve on the 54-H60-91 propeller during beta range operation. This means that the movement of the pilot valve is controlled by a system of cams and mechanical linkages, rather than by the throttle or hydraulic pressure.

The AE2100D3 PUAD lube and scavenge pump provides approximately 5 gallons per minute (GPM) at engine PTO.

The purpose of the compositor in an early ignition system is to step up the voltage high enough to break down the air gap around the ignitor plug. This is necessary to create a spark and ignite the fuel mixture in the engine. The compositor helps to increase the voltage and overcome the resistance in the air gap, allowing the spark to occur and initiate combustion.

The turbine plenum is the engine section that houses the JFS (Jet Fuel Starter) combustion section. The JFS is responsible for starting the engine by providing the initial combustion needed to power the turbine. The turbine plenum is designed to contain and direct the flow of gases produced by the JFS combustion, ensuring efficient operation of the engine.

A transducer is a device that converts one form of energy into another. In the case of engines with afterburners, the position of the exhaust nozzle needs to be converted into an electrical signal for various control and monitoring purposes. A transducer is capable of converting the mechanical position of the nozzle into an electrical signal, allowing it to be easily measured and controlled by the engine's systems. Therefore, a transducer is the most suitable device for this task.

The combustion inlet temperature is not measured in a jet engine. The temperature of the exhaust gas, turbine inlet, and fan turbine inlet are all measured as part of engine monitoring and control. However, the combustion inlet temperature is not typically measured directly, as it is difficult to access and measure accurately.

There are two primary air silencers on aircraft noise suppressors to help reduce turbine whine.

The purpose of DD form 1577 is to identify and document items that are unserviceable and condemned. This form is used to track and manage these items, ensuring that they are properly disposed of or replaced. By marking an item as unserviceable (condemned) on this form, it indicates that it is no longer usable and should not be put back into service.

The MEC (Main Engine Controller) is the component on the F108 engine that establishes the schedule for positioning the VBV's (Variable Bleed Valves). The MEC is responsible for monitoring and controlling various engine parameters, including the position of the VBV's. By establishing the schedule for positioning the VBV's, the MEC ensures optimal engine performance and efficiency.

An incipient cold compressor stall refers to a stall that is just beginning to occur at low RPM. It is characterized by a slight overtemperature, indicating that the compressor is not able to maintain the required airflow and pressure. This term is used to describe the early stage of a stall before it becomes more severe.

The correct answer is TO 2J-1-13. This is because TO stands for Technical Order, which is a publication used by the military to provide instructions and procedures for various tasks. In this case, TO 2J-1-13 specifically provides the procedures for cleaning a jet engine. Therefore, it is the most relevant and appropriate answer.

The correct answer is 23%. This means that when the engine speed reaches approximately 23%, the RGB system oil pressure is sufficient to maintain the propeller brake in the released position. This indicates that the propeller brake will not engage or stop the propeller from spinning at this engine speed.

When the null orifice on the T56 engine TD valve is set at zero, it means that there is no bypassing of fuel through the valve. Therefore, the valve will not bypass any fuel, resulting in 0% bypass.

The predetermined overspeed setting that allows the ratchets to engage is 103.5%. This means that when the speed of the system exceeds 103.5% of its normal operating speed, the ratchets will engage to prevent further acceleration and protect the system from damage.

Periodic inspections are done on aircraft parts that require infrequent inspections. These inspections are conducted at regular intervals to ensure the proper functioning and safety of the aircraft. Unlike hourly post flight inspections which are conducted after every flight, periodic inspections are done less frequently and focus on specific components or systems that do not require frequent attention. Special inspections may be conducted for specific situations or circumstances, while home station checks are performed when the aircraft returns to its home base.

All Category II DRs must be forwarded within 3 workdays (72 hours). This means that any DR falling under Category II should be reported and sent to the appropriate department or personnel within three workdays from the time it was identified. This timeframe allows for a reasonable amount of time to investigate and address the issue while ensuring timely communication and resolution.

FADEC stands for Full Authority Digital Engine Control. It is a component that controls the fuel system of the AE2100D3 engine. FADEC is responsible for monitoring and adjusting various parameters such as fuel flow, throttle position, and engine performance to ensure optimal fuel efficiency and engine operation. It uses digital technology to precisely control the engine's fuel system, providing better performance, reliability, and fuel economy compared to traditional mechanical control systems.

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The purpose of the propeller brake is to help slow down the propeller during normal engine shutdown. This is necessary to prevent the propeller from spinning freely and potentially causing damage or injury. By engaging the propeller brake, the rotation of the propeller is slowed down gradually and safely.

The correct answer is 4.33 to 1. This means that the speed is reduced by a ratio of 4.33 to 1 in the second stage of reduction. In other words, for every 4.33 units of speed, there is a reduction of 1 unit. This indicates a significant decrease in speed in the second stage of reduction.