2A251 Volume 2 UREs

Reviewed by Editorial Team
The ProProfs editorial team is comprised of experienced subject matter experts. They've collectively created over 10,000 quizzes and lessons, serving over 100 million users. Our team includes in-house content moderators and subject matter experts, as well as a global network of rigorously trained contributors. All adhere to our comprehensive editorial guidelines, ensuring the delivery of high-quality content.
Learn about Our Editorial Process
| By Catherine Halcomb
Catherine Halcomb
Community Contributor
Quizzes Created: 1442 | Total Attempts: 6,737,717
| Attempts: 209 | Questions: 90 | Updated: Mar 21, 2023
Please wait...
Question 1 / 90
0 %
0/100
Score 0/100
1. Which of the following actions is not a required action when working around moving machinery?

Explanation

Wearing loose, comfortable clothing is not a required action when working around moving machinery. This is because loose clothing can easily get caught in the machinery, leading to serious injuries or accidents. It is important to wear fitted clothing that does not have any loose ends or hanging parts that can be entangled in the machinery.

Submit
Please wait...
About This Quiz
2A251 Quizzes & Trivia

2.
We’ll put your name on your report, certificate, and leaderboard.
2. The variables upon which radiation hazards depend does not include which of the following?

Explanation

The variables upon which radiation hazards depend include time of exposure, strength of emission, and number of units operating in the area. However, the experience of the operator is not a variable that directly affects radiation hazards. While an experienced operator may have better knowledge and skills to handle radiation equipment safely, it does not directly impact the hazards themselves.

Submit
3. Who ensures the job control number is entered on the Air Force Technical Order (AFTO) Form 781A?

Explanation

The technician ensures that the job control number is entered on the Air Force Technical Order (AFTO) Form 781A. This is because the technician is responsible for completing and documenting maintenance activities, including filling out the necessary forms and ensuring all required information is accurately recorded. The job control number is an important identifier for tracking and managing maintenance tasks, so it is crucial for the technician to enter it correctly on the AFTO Form 781A.

Submit
4. Which Air Force Technical Order (AFTO) form allows you to record essential inspection and delayed maintenance data?

Explanation

The correct answer is 781K. The AFTO form 781K is used to record essential inspection and delayed maintenance data in the Air Force. This form is specifically designed for recording maintenance actions that are not completed within the required timeframe. It allows technicians to document the reasons for the delay and any additional information related to the inspection or maintenance. By using the 781K form, the Air Force can ensure that all necessary data is recorded accurately and efficiently.

Submit
5. Which portion of the tag is used to provide a "cross-check" with the aircraft forms and is inserted through the aircraft forms binder?

Explanation

The bottom portion of the tag is used to provide a "cross-check" with the aircraft forms and is inserted through the aircraft forms binder. This suggests that the bottom portion contains important information that needs to be cross-checked with the aircraft forms, indicating that it plays a crucial role in ensuring accuracy and consistency in the documentation process.

Submit
6. Which action could pose a safety hazard to personnel in an electrostatic discharge (ESD)

Explanation

The use of ionizers in an electrostatic discharge (ESD) environment could pose a safety hazard to personnel. Ionizers are designed to neutralize static charges in the air, but if not properly maintained or used incorrectly, they can generate high levels of ozone or release particles that can be harmful to human health. Therefore, the use of ionizers without proper precautions and training can potentially endanger the safety of personnel in an ESD setting.

Submit
7. Which type of cable is used to carry radio frequency (RF) power from one point to another?

Explanation

Coaxial cable is used to carry radio frequency (RF) power from one point to another. It consists of a central conductor, surrounded by an insulating layer, a metallic shield, and an outer insulating layer. The design of the coaxial cable allows for efficient transmission of RF signals without interference or loss of power. The shielded construction helps to minimize signal loss and external interference, making coaxial cable the ideal choice for carrying RF power.

Submit
8. Which structural area is designed to allow maintenance personnel to inspect or service aircraft components?

Explanation

Doors are designed to allow maintenance personnel to inspect or service aircraft components. They provide access to the interior of the aircraft, allowing technicians to easily reach and examine various systems and components. Doors are typically located in strategic areas of the aircraft, such as the fuselage, wings, or landing gear, to ensure easy access for maintenance purposes. By opening the doors, technicians can perform inspections, repairs, or routine maintenance tasks on the aircraft's components, ensuring their proper functioning and safety.

Submit
9. What happens when radiofrequency (RF) energy is absorbed in the tissue of your body?

Explanation

When radiofrequency (RF) energy is absorbed in the tissue of your body, it leads to the production of heat. RF energy is a form of electromagnetic radiation that can penetrate the body and cause molecules in the tissue to vibrate, resulting in the generation of heat. This heat production can have various effects on the body, such as warming the surrounding tissues and potentially causing damage if the temperature rises significantly.

Submit
10. The maximum noise level that is considered to be relatively safe is

Explanation

The correct answer is 84 dBA because it falls within the range of noise levels that are considered relatively safe. Noise levels above 85 dBA can cause hearing damage with prolonged exposure, so 84 dBA is just below that threshold. It is important to note that even though 84 dBA is considered relatively safe, it is still recommended to limit exposure to loud noises and use hearing protection when necessary to prevent any potential damage to hearing.

Submit
11. When is the thruflight (TH) inspection performed?

Explanation

The thruflight (TH) inspection is performed prior to takeoff and at intermediate stops. This means that the inspection is conducted before the aircraft departs for its next flight and also during any scheduled stops along the way. This ensures that the aircraft is thoroughly checked and any necessary maintenance or repairs can be carried out before continuing the journey. Performing the inspection at these specific times helps to ensure the safety and airworthiness of the aircraft throughout its flight operations.

Submit
12. When the home station check (HSC) inspection becomes due during a long range mission, it is completed at the base

Explanation

The correct answer is "to which the aircraft belongs". This means that when the home station check inspection is due during a long-range mission, it is completed at the base where the aircraft is registered or belongs to. This ensures that the inspection is carried out by the appropriate personnel who are familiar with the aircraft and its maintenance history.

Submit
13. Which type of information is required in the correction active block of the Air Force Technical Order (AFTO) Form 781A?

Explanation

In the correction active block of the Air Force Technical Order (AFTO) Form 781A, the required information is the description of the corrective action. This is important because it provides a clear and detailed account of the steps taken to correct any issues or problems identified. It helps to ensure that the necessary actions have been taken and allows for proper documentation and tracking of the corrective measures implemented. The description of the corrective action provides valuable information for future reference and analysis.

Submit
14. Which Air Force Technical Order (AFTO) form is used to document aerospace vehicle time and engine data to include operating time?

Explanation

The correct answer is 781J. The AFTO 781J form is used to document aerospace vehicle time and engine data, including operating time. This form is specifically designed for recording and tracking the usage and maintenance of aircraft and their engines. It provides a comprehensive record of the aircraft's operating hours, cycles, and other important data.

Submit
15. Twisting an optic fiber during installation or maintenance results in

Explanation

Twisting an optic fiber during installation or maintenance can cause the glass fibers within the fiber to become stretched. This stretching can disrupt the alignment of the fibers, leading to increased signal loss and reduced optical power transmission. Therefore, the correct answer is reduced optical power transmission.

Submit
16. When you are performing electrical soldering, you should always use which particular type of solder?

Explanation

When performing electrical soldering, it is important to use rosin core solder. Rosin core solder contains a flux core made of rosin, which helps to remove oxidation and promote good solder flow. This type of solder is specifically designed for electrical work and is commonly used for soldering wires, circuit boards, and other electronic components. Acid core solder, on the other hand, is not suitable for electrical soldering as it contains corrosive acid flux, which can damage electronic components. Hard and soft solder are not specifically designed for electrical work and may not provide the same level of reliability and conductivity as rosin core solder.

Submit
17. Proper care of an electric soldering iron involves

Explanation

Keeping an electric soldering iron in a proper holder when not in use is important for proper care because it ensures that the iron is stored safely and prevents it from causing any accidental damage or injuries. Placing the iron in a holder also helps to protect the soldering tip from being damaged or contaminated, which can affect its performance. Additionally, storing the iron in a holder prevents it from coming into contact with flammable materials or causing any fire hazards.

Submit
18. Before performing any type of wire repair, you must consult the procedures in technical order (TO)

Explanation

The correct answer is 1-1A-14 because it is stated in the question that before performing any type of wire repair, one must consult the procedures in technical order (TO). Therefore, the correct technical order to consult for wire repair would be 1-1A-14.

Submit
19. The greatest noise levels around an operating jet aircraft engine is located to the rear of the engine though an angle of how many degrees on either side?

Explanation

The correct answer is 45°. The greatest noise levels around an operating jet aircraft engine are located to the rear of the engine through an angle of 45° on either side. This means that the noise is most intense within a 90° cone behind the engine.

Submit
20. Which units fall under the programmed depot maintenance (PDM) inspection concept?

Explanation

The programmed depot maintenance (PDM) inspection concept applies to all units regardless of MAJCOM. This means that all units, regardless of their Air Combat Command (ACC), Air Mobility Command (AMC), or Air Force Special Operations Command (AFSOC) affiliation, are subject to PDM inspections. The PDM inspection concept is not limited to specific units or commands, but rather encompasses all units in the Air Force.

Submit
21. Malfunctions documented on the Air Force Technical Order (AFTO) Form 244, Equipment Maintenance Record, are the responsibility of

Explanation

AFTO Form 244 is used to document malfunctions in equipment maintenance. Aerospace Ground Equipment (AGE) mechanics are responsible for maintaining and repairing ground equipment used in aviation operations. Therefore, it can be inferred that they would be the ones responsible for addressing the malfunctions documented on the AFTO Form 244.

Submit
22. Except for battle damage, each discrepancy discovered is documented on the Air Force Technical Order (AFTO) Form

Explanation

The correct answer is 781A because the statement mentions that each discrepancy discovered is documented on the Air Force Technical Order (AFTO) Form. Among the options given, the AFTO Form 781A is specifically used for documenting discrepancies and corrective actions for aircraft maintenance. Therefore, it is the most appropriate choice.

Submit
23. To "flag" a condition on an aircraft that could cause damage or injury if ignored, you would use which form?

Explanation

The AF Form 1492, WARNING TAG, would be used to "flag" a condition on an aircraft that could cause damage or injury if ignored. This form serves as a visual warning to alert personnel of potential dangers and prompt them to take appropriate action to prevent accidents or further damage.

Submit
24. Shielded cable consists of

Explanation

Shielded cable consists of a metallic braid over the insulation to provide electromagnetic shielding. This shielding helps to prevent external electromagnetic interference from affecting the signals transmitted through the cable. The metallic braid acts as a barrier, blocking or absorbing the electromagnetic waves and preventing them from interfering with the signal. This ensures that the signal remains clear and free from any external disturbances, making shielded cable suitable for applications where signal integrity is crucial, such as in data transmission or sensitive electronic equipment.

Submit
25. Rosin core flux must be used for electrical soldering because it has

Explanation

Rosin core flux must be used for electrical soldering because it has noncorrosive effects. When soldering electrical components, it is important to use a flux that does not corrode or damage the materials being soldered. Rosin core flux, which is a type of soldering flux, is specifically designed to be noncorrosive, ensuring that it does not cause any harm to the electrical components. This helps to maintain the integrity and functionality of the soldered connections, making it a suitable choice for electrical soldering applications.

Submit
26. Which major aircraft structural area provides support for engines?

Explanation

Nacelles are the correct answer because they are the major aircraft structural area that provides support for engines. Nacelles are the streamlined enclosures on an aircraft that house the engines. They are typically attached to the wings or fuselage and provide support and protection for the engines.

Submit
27. Which structural area is not considered a major aircraft structural area?

Explanation

The wing carry-through is not considered a major aircraft structural area. The major structural areas of an aircraft typically include the fuselage, stabilizers, and wings. The wing carry-through refers to the structure that connects the wings to the fuselage, providing support and stability. While it is an important component, it is not considered a major structural area on its own.

Submit
28. Which physical symptom is least likely to indicate that a person is suffering from overexposure to noise?

Explanation

Unconsciousness is the least likely physical symptom to indicate overexposure to noise. While prolonged exposure to loud noise can cause symptoms such as nausea, vomiting, and dizziness, unconsciousness is not typically associated with noise exposure. Unconsciousness is more commonly linked to other factors such as head trauma, lack of oxygen, or certain medical conditions. Therefore, if a person is experiencing unconsciousness, it is unlikely to be solely caused by overexposure to noise.

Submit
29. Which inspection is designed to reduce the time an aircraft is out of commission for any given inspection?

Explanation

The phase inspection is designed to reduce the time an aircraft is out of commission for any given inspection. Unlike major inspections, which require extensive maintenance and can take the aircraft out of service for a longer period, phase inspections are more routine and can be completed more quickly. By conducting phase inspections, aircraft can undergo regular maintenance and checks without causing significant downtime, ensuring that they remain operational for a longer period.

Submit
30. Which Air Force Technical Order (AFTO) form is used to document maintenance status and servicing information of the aircraft?

Explanation

The correct answer is 781H. The Air Force Technical Order (AFTO) form 781H is used to document the maintenance status and servicing information of the aircraft. This form is specifically designed for recording historical maintenance data, including scheduled and unscheduled maintenance actions, inspections, and servicing performed on the aircraft. It provides a comprehensive record of the maintenance history, allowing for effective tracking and analysis of the aircraft's maintenance status.

Submit
31. The accumulation of an electrical charge on the surface of a material is referred to as static

Explanation

The accumulation of an electrical charge on the surface of a material is referred to as electricity. This is because electricity is the flow of electric charge, and when charge accumulates on the surface of a material, it creates an electrical charge. Static electricity is a term used to describe this accumulation of charge, which can occur through various processes such as friction, induction, or contact. The term "cling" refers to sticking or adhering to something, "discharge" refers to the release of accumulated charge, and "generation" refers to the production or creation of something, but neither of these terms specifically describe the accumulation of an electrical charge on a material's surface.

Submit
32. Which of the following is not a radiofrequency (RF) connector precaution?

Explanation

This answer is correct because ensuring a good grip when using pliers is not specifically related to radiofrequency (RF) connector precautions. The other options mentioned are all precautions that should be taken when dealing with RF connectors.

Submit
33. Crimping tools were developed to ensure crimps

Explanation

Crimping tools were developed to provide a secure and reliable mechanical connection. By using these tools, the crimps can be tightly compressed, ensuring that the wires or connectors are securely joined together. This helps to prevent any loose connections or disconnections, which can lead to faulty electrical connections or potential hazards. The crimping process also helps to maintain the integrity of the connection over time, ensuring a long-lasting and efficient electrical connection.

Submit
34. You are repairing damaged copper foil tape on an electrimagnetic pulse (EMP) hardened cable, which type of tape would you use as the final wrap to the repaired area?

Explanation

Silicone self-bonding tape would be the ideal choice for the final wrap to the repaired area of the damaged copper foil tape on an electromagnetic pulse (EMP) hardened cable. This type of tape is known for its self-adhesive properties and ability to bond to itself, creating a secure and durable seal. It is also resistant to extreme temperatures, moisture, and chemicals, making it suitable for protecting the repaired area from further damage or environmental factors. Additionally, silicone self-bonding tape offers excellent electrical insulation properties, which is crucial for maintaining the integrity of the EMP hardened cable.

Submit
35. The impedance of a radio frequency (RF) transmission line and load do not match. In addition, the reflected wave and the applied wave are on the line at the same time and are creating a wave that is stationary on the line. What is this stationary wave called?

Explanation

When the impedance of a RF transmission line and load do not match, a portion of the transmitted wave is reflected back towards the source. This creates interference between the reflected wave and the applied wave, resulting in a stationary wave pattern known as a standing wave. In a standing wave, certain points along the transmission line experience maximum and minimum amplitudes, creating areas of constructive and destructive interference. This phenomenon is commonly observed in RF systems and can cause signal degradation or other issues.

Submit
36. Which type of inspection is a flight preparedness check?

Explanation

A flight preparedness check is a type of inspection that is conducted before a flight takes off. This inspection is performed to ensure that the aircraft is in proper working condition and ready for flight. It involves checking various components and systems of the aircraft, such as the fuel, oil, landing gear, and controls. The purpose of this inspection is to identify any potential issues or problems that may affect the safety or performance of the aircraft during the flight. Therefore, the correct answer is "Preflight."

Submit
37. Which type of inspection is designed to detect defects that might have developed during ground operation of the aircraft?

Explanation

End-of-runway inspection is designed to detect defects that might have developed during ground operation of the aircraft. This type of inspection is conducted after the aircraft has completed its taxiing and is ready for takeoff. It involves a thorough inspection of the aircraft's exterior, including checking for any signs of damage, loose parts, or fluid leaks. This inspection ensures that the aircraft is in proper working condition before it takes off, minimizing the risk of any potential defects causing issues during the flight.

Submit
38. One way of pressure and moisture sealing the back of a connector is to use

Explanation

Silicone tape is a suitable option for pressure and moisture sealing the back of a connector. Silicone tape is known for its excellent sealing properties, as it creates a tight and waterproof seal when wrapped around the connector. It is also flexible and can conform to the shape of the connector, ensuring a secure and effective seal. Additionally, silicone tape is resistant to high temperatures and UV rays, making it durable and long-lasting. Therefore, silicone tape is a reliable choice for pressure and moisture sealing in connector applications.

Submit
39. The heat and air pressure required for proper installation of heat shrink products is controlled by the

Explanation

The tool operator is responsible for controlling the heat and air pressure required for proper installation of heat shrink products. They have the knowledge and expertise to adjust the temperature controller and air/nitrogen regulator to the appropriate levels. The tool operator also operates the tubular heating element, which provides the necessary heat for the shrinkage process. Therefore, the tool operator plays a crucial role in ensuring the correct heat and air pressure for successful installation of heat shrink products.

Submit
40. Which display is not part of an engine indicating system?

Explanation

The water temperature display is not part of an engine indicating system because it is not directly related to the functioning or performance of the engine. Engine indicating systems typically include displays for fuel flow, oil quantity, and engine vibration, as these parameters directly affect the engine's operation. Water temperature, on the other hand, is more relevant to the cooling system of the engine rather than its direct operation.

Submit
41. When approaching overheated aircraft wheels, always approach the wheel

Explanation

When approaching overheated aircraft wheels, it is recommended to approach from the front or behind the wheel. This is because approaching from the side of the wheel or at a 45° angle to the wheel can put the person at risk of being in the path of a potential blowout. Approaching from the front or behind the wheel allows for a safer distance and reduces the risk of injury in case of a blowout.

Submit
42. Which amplitude-modulated (AM) transmitter stage isolates the master oscillator from the multiplier and amplifier load?

Explanation

A buffer amplifier is used in an AM transmitter stage to isolate the master oscillator from the multiplier and amplifier load. It acts as a buffer between the oscillator and the load, preventing any interference or distortion caused by the load from affecting the oscillator. This ensures that the oscillator operates independently and provides a stable and clean signal to the multiplier and amplifier stages.

Submit
43. Which condition helps to dissipate and lessen the effects of electrostatic discharges?

Explanation

Humid air helps to dissipate and lessen the effects of electrostatic discharges. When the air is humid, it contains water molecules which can conduct electricity. This helps to neutralize any electrostatic charges that may be present, reducing the likelihood of a discharge occurring. In contrast, dry air can increase the buildup of static electricity and make it more likely for a discharge to happen. Therefore, maintaining a humid environment can be beneficial in minimizing the effects of electrostatic discharges.

Submit
44. Which option is not a flight line precaution used to protect electrostatic discharge sensitive (ESDS) components?

Explanation

not-available-via-ai

Submit
45. Which feature is not an advantage of fiber optic cables over copper wire?

Explanation

Fiber optic cables have several advantages over copper wire, including immunity to electromagnetic interference, low attenuation, and light weight. However, one disadvantage of fiber optic cables is their higher cost compared to copper wire.

Submit
46. Which type of solderless connector is used to permit easy and efficient connections to electrical equipment?

Explanation

A terminal lug is a type of solderless connector that is used to permit easy and efficient connections to electrical equipment. It is designed to securely connect wires to terminals or electrical devices without the need for soldering. Terminal lugs are commonly used in electrical installations, automotive wiring, and industrial applications. They provide a reliable and durable connection, ensuring proper conductivity and reducing the risk of loose or faulty connections.

Submit
47. Which of the following is not considered to be a general precaution when lacing or tying wire groups or bundles?

Explanation

The other options provide general precautions for lacing or tying wire groups or bundles, such as preventing slipping, avoiding the use of ties inside a conduit, and starting ties far enough back from connectors to avoid spreading of contacts. However, tying all wire groups or bundles twelve inches or less apart is not considered a general precaution. This may actually be too close and could lead to tangling or interference between the wires.

Submit
48. How does independent positioning determine subsystems function of aircraft systems?

Explanation

Independent positioning determines the subsystems function of aircraft systems by being able to operate without relying on any ground equipment. This means that the aircraft's systems can function autonomously, without the need for external support or guidance. This independence allows for greater flexibility, reliability, and efficiency in the operation of the aircraft systems, as they are not reliant on external factors or equipment.

Submit
49. The Air Force Technical Order (AFTO) Form 781-series would not be used to document aircraft

Explanation

The Air Force Technical Order (AFTO) Form 781-series is a documentation form used in the Air Force to record various aspects of aircraft maintenance and operations. However, it would not be used to document component repairs. This is because component repairs require more detailed and specific documentation, which is typically done through separate forms or procedures. The AFTO Form 781-series is more commonly used for inspections, flight records, and configurations, as these can be easily recorded and tracked using this standardized form.

Submit
50. Who is responsible for documenting engine cycles on an Air Force Technical Order (AFTO) Form 781H?

Explanation

The pilot is responsible for documenting engine cycles on an Air Force Technical Order (AFTO) Form 781H. This form is used to track and record the usage and maintenance of aircraft engines. As the person operating the aircraft, the pilot is in the best position to accurately document the engine cycles, which include information such as start, shutdown, and duration of engine operation. The pilot's role in recording this information ensures that accurate maintenance records are maintained and helps in planning and scheduling engine maintenance activities.

Submit
51. What is the purpose of prewaxing cotton or linen tape when used for wire bundling?

Explanation

Prewaxing cotton or linen tape when used for wire bundling promotes moisture and fungus resistance. By applying wax to the tape, it creates a barrier that helps to repel moisture and prevents the growth of fungus. This is important in wire bundling applications as moisture can cause damage to the wires and lead to electrical issues. Additionally, fungus growth can deteriorate the tape and compromise its effectiveness in securing the wires. Therefore, prewaxing the tape helps to enhance its durability and longevity in moist environments.

Submit
52. The minimum safe distance from a high-frequency (HF) antenna when the associated transmitter is radiating power is

Explanation

The minimum safe distance from a high-frequency (HF) antenna when the associated transmitter is radiating power is 5 feet. This distance is necessary to ensure that individuals are not exposed to excessive levels of electromagnetic radiation, which can be harmful to human health. By maintaining a distance of 5 feet, the risk of potential health hazards associated with high-frequency antenna radiation is minimized.

Submit
53. When are acceptance inspections performed?

Explanation

Acceptance inspections are performed when newly assigned equipment arrives. This is the point at which the equipment is checked to ensure that it is in proper working order and meets the necessary requirements. These inspections are crucial to ensure that the equipment is ready for use and to identify any potential issues or defects that may need to be addressed before it can be put into service.

Submit
54. The circuit used in an amplitude-modulated (AM) transmitter to bring the oscillator frequency up to the designed frequency required for carrier wave operation is a

Explanation

A frequency multiplier is used in an amplitude-modulated (AM) transmitter to increase the oscillator frequency to the desired frequency for carrier wave operation. This is necessary because the carrier wave needs to be at a specific frequency in order to transmit the modulated signal effectively. The frequency multiplier circuit takes the oscillator frequency and multiplies it by a certain factor to achieve the desired carrier wave frequency. This allows for accurate and efficient transmission of the modulated signal.

Submit
55. A major drawback in using a single-sideband (SSB) receiver over and amplitude-modulated (AM) receiver is the

Explanation

The major drawback in using a single-sideband (SSB) receiver over an amplitude-modulated (AM) receiver is the need for critical frequency stability. This means that the SSB receiver requires a more precise and stable frequency in order to properly demodulate the signal and extract the desired information. In contrast, an AM receiver can tolerate some frequency variations and still be able to detect and demodulate the signals. Therefore, the need for critical frequency stability is a disadvantage of using an SSB receiver.

Submit
56. Which type of radio frequency (RF) transmission line loss is a result of skin effect?

Explanation

Copper is the correct answer because skin effect is a phenomenon where the flow of current is concentrated near the surface of a conductor, resulting in increased resistance and loss. This effect is more pronounced at higher frequencies, such as those used in RF transmission lines. Since copper is a commonly used conductor in RF transmission lines, the loss due to skin effect is a significant factor to consider.

Submit
57. Guidelines for different areas of fire prevention on the flight line can be found in the Air Force Occupational Safety and Health (AFOSH) Standard

Explanation

The correct answer is 91-56. The Air Force Occupational Safety and Health (AFOSH) Standard 91-56 provides guidelines for different areas of fire prevention on the flight line. This standard outlines the necessary safety measures and precautions to prevent fires and ensure the safety of personnel and equipment. It covers topics such as fire prevention plans, fire detection and suppression systems, emergency procedures, and training requirements. By following the guidelines outlined in AFOSH Standard 91-56, the Air Force can effectively mitigate the risks of fires on the flight line.

Submit
58. Part V of the Air Force Technical Order (AFTO) Form 244 is used to document

Explanation

Part V of the Air Force Technical Order (AFTO) Form 244 is used to document maintenance/delayed discrepancies. This section is specifically designed to record any issues or discrepancies found during maintenance activities that may cause a delay in the completion of the task. It allows technicians to document and track these discrepancies, ensuring that they are addressed and resolved in a timely manner. This documentation is crucial for maintaining the overall operational readiness and safety of the aircraft.

Submit
59. One purpose of crimper positioners is to

Explanation

Crimper positioners are used to put pin contacts in the proper position. This means that they are responsible for ensuring that the pin contacts are correctly aligned and positioned before the crimping process takes place. By doing so, the crimper positioners help to ensure the accuracy and quality of the crimping operation, as the pin contacts need to be in the correct position for a secure and reliable connection to be made.

Submit
60. As a flight line technician, you can repair up to which percent of which circumference of an electromagnetic pulse (EMP) hardened cable?

Explanation

As a flight line technician, you can repair up to 25 percent of the outer shield of an electromagnetic pulse (EMP) hardened cable. This means that if the outer shield of the cable is damaged, you can repair up to a quarter of it. Repairing the outer shield helps to protect the cable from EMP, which is a burst of electromagnetic radiation that can cause damage to electronic equipment. Repairing a portion of the outer shield allows the cable to continue functioning properly and maintain its EMP-hardened capabilities.

Submit
61. Within a typical amplitude-modulated (AM) superheterodyne receiver, the process used to tune two or more circuits with a single control is considered, which type of tuning?

Explanation

In a typical AM superheterodyne receiver, the process of tuning two or more circuits with a single control is known as "ganged" tuning. This means that when the control is adjusted, it simultaneously adjusts the tuning of multiple circuits in synchronization. This allows for easier and more efficient tuning of the receiver, as all the circuits are tuned together.

Submit
62. Which option is not a basic characteristic that can vary in a modulating wave or signal?

Explanation

Rate is not a basic characteristic that can vary in a modulating wave or signal. Frequency refers to the number of cycles or oscillations per unit of time, amplitude represents the magnitude or strength of the wave, and phase refers to the position of the wave in its cycle. Rate, on the other hand, does not typically apply to the variations in a modulating wave or signal.

Submit
63. When the modulation in a frequency-modulation (FM) signal increases the number of sidebands increase, carrier power increases, and the total power

Explanation

In frequency modulation (FM), the modulation increases the number of sidebands, which are additional frequencies generated around the carrier frequency. However, the modulation does not affect the power of the carrier signal itself. Therefore, the total power of the FM signal remains the same.

Submit
64. The ability of a radio receiver to reproduce weak signals is called

Explanation

Sensitivity refers to the ability of a radio receiver to reproduce weak signals. A receiver with high sensitivity can detect and amplify low-power signals, allowing for better reception and clearer audio quality. This is an important factor in radio communication systems, as it determines the range and effectiveness of the receiver in picking up weak or distant signals.

Submit
65. A receiving radio antenna receives radio frequency signals by

Explanation

The correct answer is "electromagnetic fields impressing a voltage across the antenna thus causing current to flow." When a radio antenna receives radio frequency signals, the electromagnetic fields from the signals induce a voltage across the antenna. This voltage causes a current to flow through the antenna, which is then amplified and processed to extract the desired information from the radio frequency signals.

Submit
66. The radio frequency (RF) transmission line whose chief advantage is its ability to minimize radiation losses and noise pickup from other lines is the

Explanation

A flexible coaxial line is a type of radio frequency (RF) transmission line that is designed with a central conductor surrounded by an insulating layer, which is then surrounded by a metallic shield. This shield helps to minimize radiation losses and prevents noise pickup from other lines. The flexibility of the coaxial line allows for easy installation and routing in various applications. Therefore, a flexible coaxial line is the best choice among the given options for minimizing radiation losses and noise pickup.

Submit
67. Which inspection is more extensive than the hourly or basic postflight inspections and covers certain parts, areas, and systems of the aircraft that require less frequent inspection?

Explanation

Periodic inspections are more extensive than hourly or basic postflight inspections because they cover certain parts, areas, and systems of the aircraft that require less frequent inspection. These inspections are conducted at regular intervals and involve a thorough examination of specific components to ensure their proper functioning and identify any potential issues or wear and tear that may have occurred over time.

Submit
68. To achieve amplitude-modulated (AM) modulation, which amplifier is used to ensure the output signal contains frequencies not present in the input signal?

Explanation

Nonlinear amplifiers are used to achieve amplitude-modulated (AM) modulation in order to ensure that the output signal contains frequencies that are not present in the input signal. Unlike linear amplifiers, which maintain the same shape as the input signal, nonlinear amplifiers introduce distortion and create new frequencies through the process of modulation. This is essential for generating the sidebands necessary for AM modulation. Therefore, a nonlinear amplifier is the correct choice to achieve AM modulation.

Submit
69. In single-sideband (SSB) transmitter, the balance modulator's output consists of

Explanation

In a single-sideband (SSB) transmitter, the balance modulator is responsible for generating the upper and lower sidebands. The balance modulator combines the audio signal with a carrier wave to produce the sidebands. Since SSB transmission only requires one sideband to transmit the audio signal, the other sideband is suppressed. Therefore, the output of the balance modulator in an SSB transmitter consists of both the upper and lower sidebands.

Submit
70. Which option is not a type of connector coupling?

Explanation

The question asks for an option that is not a type of connector coupling. The options "Friction," "Bayonet," and "Threaded" are all types of connector couplings commonly used in various industries. However, "Insertion" is not a recognized type of connector coupling. Therefore, the correct answer is "Insertion."

Submit
71. The two advantages of using a single-sideband (SSB) receiver over an amplitude-modulation (AM) receiver is which option with more or less in a small portion of the frequency spectrum?

Explanation

A single-sideband (SSB) receiver has a narrower receiver bandpass compared to an amplitude-modulation (AM) receiver. This means that it can selectively receive a smaller portion of the frequency spectrum, allowing for better signal filtering and reducing interference from other signals. Additionally, the SSB receiver has the ability to place more signals within this narrower bandpass, making it more efficient in terms of spectrum utilization.

Submit
72. A transmitting radio antenna is considered a transducer because it

Explanation

A transmitting radio antenna is considered a transducer because it converts energy to magnetic and electrical fields of force. This means that it takes the electrical energy provided to it and converts it into a combination of magnetic and electrical fields that can be transmitted as radio frequency energy. This conversion process allows the antenna to effectively transmit the radio frequency energy to distant locations.

Submit
73. In a frequency-modulation (FM) signal, what determines the rate at which deviaton takes place?

Explanation

The rate at which deviation takes place in a frequency-modulation (FM) signal is determined by the frequency of the modulating signal. In FM, the carrier signal's frequency is varied according to the changes in the modulating signal's frequency. As the modulating signal's frequency increases or decreases, the carrier signal's frequency deviates at a corresponding rate. Therefore, the frequency of the modulating signal directly affects the rate of deviation in an FM signal.

Submit
74. Whitin a single-sideband (SSB) transmitter, frequency stability is controlled by

Explanation

In a single-sideband (SSB) transmitter, frequency stability is controlled by carefully controlled oscillators. These oscillators are responsible for generating the carrier frequency and maintaining its stability. By carefully controlling the oscillators, any drift or variation in frequency can be minimized, ensuring that the transmitted signal remains stable and accurate. This is crucial in SSB transmission as it helps to prevent signal distortion and interference, allowing for clear and reliable communication.

Submit
75. Which inspection includes a review of the forms for current status, a visual inspection of equipment for defects, and adequate servicing?

Explanation

Operator inspection includes a review of the forms for current status, a visual inspection of equipment for defects, and adequate servicing. This type of inspection is typically performed by the operator of the equipment or machinery to ensure that it is in proper working condition and to identify any potential issues or defects. The operator is responsible for regularly inspecting and maintaining the equipment to ensure its safe and efficient operation.

Submit
76. What is the bandwitdth of a frequency-modulation (FM) signal if a 5-kilohertz (kHz) modulating tone causes the gerneration of 12 sidebands above and below the carrier frequency?

Explanation

The bandwidth of a frequency-modulation (FM) signal is determined by the number of sidebands generated above and below the carrier frequency. In this case, a 5-kilohertz (kHz) modulating tone causes the generation of 12 sidebands. Since there are 12 sidebands above the carrier frequency and 12 sidebands below the carrier frequency, the total number of sidebands is 24. Each sideband contributes to the bandwidth of the FM signal. Therefore, the bandwidth is 24 times the modulating tone frequency, which is 24 times 5 kHz, equal to 120 kHz.

Submit
77. The ratio of the maximum radiation intensity of a given directional radio antenna to the radiation intensity of a nondirectional radio antenna using the same power input is known as antenna

Explanation

The ratio of the maximum radiation intensity of a given directional radio antenna to the radiation intensity of a nondirectional radio antenna using the same power input is known as antenna gain.

Submit
78. The single-sideband (SSB) transmitter circuit that increases the power output without introducing distortion is the

Explanation

A linear power amplifier is a type of amplifier that increases the power of a signal without introducing distortion. It operates in a linear region of its transfer characteristic curve, ensuring that the output signal is an amplified replica of the input signal. This makes it suitable for SSB transmission, where distortion can cause interference and degrade the quality of the signal. A balanced amplifier, power synthesizer, or balanced modulator may not provide the same level of linearity and distortion-free amplification as a linear power amplifier, making it the correct choice in this scenario.

Submit
79. Which radio receiver's characteristic is a major limiting factor of receiever sensitivity to very low-signal inputs?

Explanation

The characteristic of a radio receiver that is a major limiting factor of receiver sensitivity to very low-signal inputs is noise. Noise refers to any unwanted signals or interference that can disrupt the desired signal. In a radio receiver, noise can come from various sources such as atmospheric conditions, electrical equipment, or electronic components within the receiver itself. This noise can mask or distort the weak signals that the receiver is trying to pick up, reducing its sensitivity and making it harder to detect and interpret the desired signal.

Submit
80. Which type of radio frequency transmission wire has principle disadvantages of high-radiation losses and noise pickup due to the lack of shielding?

Explanation

The principle disadvantages of high-radiation losses and noise pickup are associated with parallel two-wire radio frequency transmission wire. This type of wire lacks shielding, which allows for the radiation of the signal and also makes it susceptible to picking up external noise. Shielded pair, air coaxial line, and flexible coaxial line, on the other hand, provide shielding to minimize these issues.

Submit
81. Which device is not a circuit in a frequency-modulation (FM) transmitter's automatic frequency control circuitry?

Explanation

The bandpass filter is not a circuit in a frequency-modulation (FM) transmitter's automatic frequency control circuitry. The automatic frequency control circuitry is responsible for maintaining the transmitter's frequency stability. The crystal oscillator generates a stable frequency reference, the frequency converter converts the baseband signal to the desired RF frequency, and the frequency discriminator detects and demodulates the FM signal. However, the bandpass filter is used to filter out unwanted frequencies and is not directly involved in the automatic frequency control circuitry.

Submit
82. Frequency-modulation (FM) demodulation is the process of detecting variations in which area of the signal?

Explanation

Frequency-modulation (FM) demodulation is the process of detecting variations in the frequency of the signal. In FM modulation, the frequency of the carrier signal is varied in proportion to the amplitude of the modulating signal. Therefore, in order to demodulate the FM signal and retrieve the original information, it is necessary to detect and analyze the variations in frequency.

Submit
83. The property of interchangeability for a radio antenna is known as

Explanation

Reciprocity refers to the property of interchangeability for a radio antenna. This means that the antenna can transmit and receive signals equally well in any direction. In other words, the antenna's performance is the same regardless of whether it is used for transmitting or receiving signals. This property is important in various applications, such as wireless communication systems, where the same antenna can be used for both transmitting and receiving data.

Submit
84. Which piece of equipment material is not a type of solderless connector?

Explanation

A connector splice is not a type of solderless connector because it involves joining two wires or cables together using a soldering technique. Solderless connectors, on the other hand, are designed to make electrical connections without the need for soldering. They typically use mechanical means such as clamps, screws, or compression fittings to secure the wires or cables together.

Submit
85. The purpose of the limiter circuit in a frequency-modulation (FM) receiver is to

Explanation

The purpose of the limiter circuit in a frequency-modulation (FM) receiver is to remove amplitude variations from the intermediate-frequency signal. In FM modulation, the frequency of the carrier signal is varied according to the amplitude of the modulating signal. This modulation process can introduce unwanted amplitude variations in the signal. The limiter circuit is designed to eliminate these variations and produce a constant amplitude signal, which is easier to process and demodulate.

Submit
86. The radio frequency line that has uniform capacitance between the conductors throughout the length of the line is the

Explanation

A shielded pair is a type of radio frequency line that has uniform capacitance between the conductors throughout its length. This means that the capacitance remains constant along the entire line, resulting in consistent electrical characteristics. The shielded pair consists of two conductors, with one conductor surrounded by a metallic shield to provide protection against external interference. This design ensures that the capacitance between the conductors remains uniform, making the shielded pair the correct answer.

Submit
87. Which option is not an advantage of single sideband over double sideband?

Explanation

Single sideband (SSB) modulation offers several advantages over double sideband (DSB) modulation. It provides power efficiency by transmitting only one sideband, allowing for more efficient use of power. It also conserves spectrum by transmitting only a single sideband, reducing the bandwidth required for transmission. Additionally, SSB modulation offers a higher signal-to-noise ratio by eliminating one sideband and the carrier, resulting in a cleaner and more reliable signal. However, frequency stability is not a specific advantage of SSB over DSB. Both modulation techniques can provide stable frequency transmission.

Submit
88. In a frequency-modulation (FM) signal, the amount of separation between the sideband frequencies is determined by the

Explanation

The amount of separation between the sideband frequencies in a frequency-modulation (FM) signal is determined by the amount equal to the modulating signal. This means that the frequency deviation, or the change in carrier frequency, is directly proportional to the amplitude of the modulating signal. As the amplitude of the modulating signal increases, the frequency deviation also increases, resulting in a wider separation between the sideband frequencies. Conversely, a smaller amplitude of the modulating signal would result in a narrower separation between the sideband frequencies.

Submit
89. The basic difference between the single-sideband (SSB) receiver and a conventional superheterodyne receiver is that the single-sideband receiver uses a

Explanation

The basic difference between the single-sideband (SSB) receiver and a conventional superheterodyne receiver is that the single-sideband receiver uses a special detector and carrier reinsertion oscillator. This means that the SSB receiver has a unique circuitry that allows it to extract the original signal from the sidebands of the modulated carrier wave. The special detector is responsible for demodulating the sidebands, while the carrier reinsertion oscillator helps to regenerate the carrier frequency. This combination of components enables the SSB receiver to effectively receive and decode single-sideband signals.

Submit
90. Which circuit produces the sidebands in a single-sideband (SSB) transmitter?

Explanation

A balanced modulator is responsible for producing the sidebands in a single-sideband (SSB) transmitter. It combines the carrier signal with the modulating signal, resulting in the generation of upper and lower sidebands. By suppressing the carrier and one of the sidebands, SSB transmission allows for more efficient use of bandwidth. The balanced modulator achieves this by multiplying the modulating signal with the carrier signal, effectively shifting the spectrum to one side.

Submit
View My Results
Cancel
  • All
    All (90)
  • Unanswered
    Unanswered ()
  • Answered
    Answered ()
Which of the following actions is not a required action when working...
The variables upon which radiation hazards depend does not include...
Who ensures the job control number is entered on the Air Force...
Which Air Force Technical Order (AFTO) form allows you to record...
Which portion of the tag is used to provide a "cross-check" with the...
Which action could pose a safety hazard to personnel in an...
Which type of cable is used to carry radio frequency (RF) power from...
Which structural area is designed to allow maintenance personnel to...
What happens when radiofrequency (RF) energy is absorbed in the tissue...
The maximum noise level that is considered to be relatively safe is
When is the thruflight (TH) inspection performed?
When the home station check (HSC) inspection becomes due during a long...
Which type of information is required in the correction active block...
Which Air Force Technical Order (AFTO) form is used to document...
Twisting an optic fiber during installation or maintenance results in
When you are performing electrical soldering, you should always use...
Proper care of an electric soldering iron involves
Before performing any type of wire repair, you must consult the...
The greatest noise levels around an operating jet aircraft engine is...
Which units fall under the programmed depot maintenance (PDM)...
Malfunctions documented on the Air Force Technical Order (AFTO) Form...
Except for battle damage, each discrepancy discovered is documented on...
To "flag" a condition on an aircraft that could cause damage or injury...
Shielded cable consists of
Rosin core flux must be used for electrical soldering because it has
Which major aircraft structural area provides support for engines?
Which structural area is not considered a major aircraft structural...
Which physical symptom is least likely to indicate that a person is...
Which inspection is designed to reduce the time an aircraft is out of...
Which Air Force Technical Order (AFTO) form is used to document...
The accumulation of an electrical charge on the surface of a material...
Which of the following is not a radiofrequency (RF) connector...
Crimping tools were developed to ensure crimps
You are repairing damaged copper foil tape on an electrimagnetic pulse...
The impedance of a radio frequency (RF) transmission line and load do...
Which type of inspection is a flight preparedness check?
Which type of inspection is designed to detect defects that might have...
One way of pressure and moisture sealing the back of a connector is to...
The heat and air pressure required for proper installation of heat...
Which display is not part of an engine indicating system?
When approaching overheated aircraft wheels, always approach the wheel
Which amplitude-modulated (AM) transmitter stage isolates the master...
Which condition helps to dissipate and lessen the effects of...
Which option is not a flight line precaution used to protect...
Which feature is not an advantage of fiber optic cables over copper...
Which type of solderless connector is used to permit easy and...
Which of the following is not considered to be a general precaution...
How does independent positioning determine subsystems function of...
The Air Force Technical Order (AFTO) Form 781-series would not be used...
Who is responsible for documenting engine cycles on an Air Force...
What is the purpose of prewaxing cotton or linen tape when used for...
The minimum safe distance from a high-frequency (HF) antenna when the...
When are acceptance inspections performed?
The circuit used in an amplitude-modulated (AM) transmitter to bring...
A major drawback in using a single-sideband (SSB) receiver over and...
Which type of radio frequency (RF) transmission line loss is a result...
Guidelines for different areas of fire prevention on the flight line...
Part V of the Air Force Technical Order (AFTO) Form 244 is used to...
One purpose of crimper positioners is to
As a flight line technician, you can repair up to which percent of...
Within a typical amplitude-modulated (AM) superheterodyne receiver,...
Which option is not a basic characteristic that can vary in a...
When the modulation in a frequency-modulation (FM) signal increases...
The ability of a radio receiver to reproduce weak signals is called
A receiving radio antenna receives radio frequency signals by
The radio frequency (RF) transmission line whose chief advantage is...
Which inspection is more extensive than the hourly or basic postflight...
To achieve amplitude-modulated (AM) modulation, which amplifier is...
In single-sideband (SSB) transmitter, the balance modulator's output...
Which option is not a type of connector coupling?
The two advantages of using a single-sideband (SSB) receiver over an...
A transmitting radio antenna is considered a transducer because it
In a frequency-modulation (FM) signal, what determines the rate at...
Whitin a single-sideband (SSB) transmitter, frequency stability is...
Which inspection includes a review of the forms for current status, a...
What is the bandwitdth of a frequency-modulation (FM) signal if a...
The ratio of the maximum radiation intensity of a given directional...
The single-sideband (SSB) transmitter circuit that increases the power...
Which radio receiver's characteristic is a major limiting factor of...
Which type of radio frequency transmission wire has principle...
Which device is not a circuit in a frequency-modulation (FM)...
Frequency-modulation (FM) demodulation is the process of detecting...
The property of interchangeability for a radio antenna is known as
Which piece of equipment material is not a type of solderless...
The purpose of the limiter circuit in a frequency-modulation (FM)...
The radio frequency line that has uniform capacitance between the...
Which option is not an advantage of single sideband over double...
In a frequency-modulation (FM) signal, the amount of separation...
The basic difference between the single-sideband (SSB) receiver and a...
Which circuit produces the sidebands in a single-sideband (SSB)...
Alert!

Back to Top Back to top
Advertisement