EASA Part 66 – Module 07 – Practise exam questions

Based on our vast experience with EASA PART 66 examination questions and question databanks, we have prepared a practice example of questions with explanations to practice for your next exam.

Disclaimer: This questions are for training purposes only! They are in no way appearing on Suntech’s’ controlled examination sessions.

At the end of the questions you are most welcome to comment, debate and ask questions.

Module 7: Maintenance Practices

1. Under which of the following conditions is aircraft refueling strictly prohibited for safety reasons?

   A. When the aircraft’s navigation and landing lights are in operation.
   B. When the Auxiliary Power Unit (APU) is running to supply power.
   C. When operating weather radar or similar high-frequency radio equipment within 10 metres (30 feet).

   Correct Answer: C. When operating weather radar or similar high-frequency radio equipment within 10 metres (30 feet).
   Explanation: Operating high-frequency radar equipment close to refueling activities creates a significant ignition risk. The electromagnetic energy can induce sparks in the fuel vapor-rich environment, potentially leading to a fire. A minimum safety distance is therefore mandatory.

 


2. A Carbon Dioxide (CO2) fire extinguisher is most suitable for which combination of fire classes?

   A. Fires involving flammable solids, liquids, and energized electrical equipment.
   B. Fires involving solid materials, flammable liquids, and combustible metals.
   C. Fires involving only flammable liquids and combustible metals.

   Correct Answer: A. Fires involving flammable solids, liquids, and energized electrical equipment.
   Explanation: CO2 extinguishers function by displacing oxygen and cooling the burning material. They are highly effective for Class B (liquid) and Class C (electrical) fires. While they have some effect on Class A (solid) fires, they are not the primary choice. They must NEVER be used on Class D (combustible metal) fires, as a dangerous chemical reaction can occur.

 


3. What is the standard practice for lubrication when utilizing a reamer to finish a hole?

   A. Use lard oil exclusively, regardless of the drilling lubricant.
   B. No lubricant should be applied when using a reamer.
   C. The same cutting fluid that was used for the drilling operation should be used.

   Correct Answer: C. The same cutting fluid that was used for the drilling operation should be used.
   Explanation: To ensure dimensional accuracy, a high-quality surface finish, and to prevent contamination, it is standard practice to use the same lubricant for both the drilling and reaming processes. This maintains consistency and is crucial for the tool’s performance.

 


4. When preparing to drill a 1/4 inch hole in a sheet of titanium, what is the correct initial action to ensure accuracy?

   A. Directly begin drilling with the 1/4 inch drill bit.
   B. Create a precise starting mark using a centre punch.
   C. First, drill a smaller pilot hole to guide the final drill bit.

   Correct Answer: B. Create a precise starting mark using a centre punch.
   Explanation: Titanium is a hard material, and a drill bit can easily ‘wander’ or slip on its surface, leading to an inaccurately placed hole. Using a centre punch to create a small indentation provides a positive guide for the drill bit to start in the correct location.

 


5. A torque of 300 lbs.in. is required. If using a 12-inch torque wrench with a 3-inch extension, what value must be indicated on the wrench’s dial to achieve the correct final torque?

   A. 240 lbs.in.
   B. 375 lbs.in.
   C. 280 lbs.in.

   Correct Answer: A. 240 lbs.in.
   Explanation: When an extension is used, the effective lever arm is increased, meaning the torque applied to the fastener is greater than the torque shown on the wrench dial. The correct dial setting is calculated with the formula: WrenchSetting=DesiredTorque×[L/(L+E)], where L is the wrench length and E is the extension length. Therefore, the calculation is 300×[12/(12+3)]=240lbs.in.

 


6. What term is used in engineering to define the difference between the maximum and minimum permissible limits of a dimension?

   A. Fit.
   B. Deviation.
   C. Tolerance.

   Correct Answer: C. Tolerance.
   Explanation: Tolerance is a fundamental engineering term. It represents the total allowable variation for a specific dimension to ensure a part can be manufactured and function correctly. It is the absolute difference between the upper and lower limits.

 


7. To maximize their service life, what are the proper storage conditions for elastomeric components such as rubber seals and hoses?

   A. In a well-lit and warm environment.
   B. In a cool, dark area shielded from direct light and ozone.
   C. In a warm and high-humidity environment.

   Correct Answer: B. In a cool, dark area shielded from direct light and ozone.
   Explanation: Elastomeric materials degrade when exposed to heat, UV light, and ozone. To preserve their elasticity and prevent premature aging and cracking, they must be stored in a cool, dark, controlled environment.

 


8. How should the machining technique for stainless steel differ from that used for aluminum alloy sheet?

   A. Drill at a lower speed with more pressure applied to the drill.
   B. Drill at a higher speed with less pressure applied to the drill.
   C. Drill at a lower speed with less pressure applied to the drill.

   Correct Answer: A. Drill at a lower speed with more pressure applied to the drill.
   Explanation: Stainless steel has a tendency to work-harden if excessive heat is generated or if the tool rubs instead of cuts. Therefore, a lower rotational speed is used to minimize heat, while firm, positive pressure ensures the cutting edges are constantly biting into the material, preventing work-hardening.

 


9. When calibrating a torque wrench with a handle length of 15 inches, what load must be applied to the handle to produce a torque value of 120 lbs.in.?

   A. 10 lbs.
   B. 6 lbs.
   C. 8 lbs.

   Correct Answer: C. 8 lbs.
   Explanation: Torque is the product of force and the perpendicular distance from the point of rotation (Torque=Force×Length). To find the required force, the formula is rearranged to Force=Torque/Length. Therefore, the calculation is 120lbs.in./15in.=8lbs.

 


10. What type of lubricant is generally specified for drilling operations on brass?

    A. Lard oil.
    B. Paraffin.
    C. None.

    Correct Answer: C. None.
    Explanation: Brass has excellent machinability and is often referred to as being ‘free-machining’. In most cases, it can be drilled effectively without any lubricant, as the chips tend to break away cleanly without galling or binding to the tool.

 


11. What is the correct technique for using a hand reamer to finish a hole?

    A. Rotate the reamer only in the cutting direction, both when inserting and removing it.
    B. Rotate the reamer in both directions to achieve a smoother finish.
    C. Apply significant pressure when starting and reduce pressure at the end.

    Correct Answer: A. Rotate the reamer only in the cutting direction, both when inserting and removing it.
    Explanation: A reamer is designed to cut only in one direction (typically clockwise). Rotating it backward will dull the cutting edges and can damage the surface finish of the hole. It must be turned only in the cutting direction for the entire operation.

 


12. What is the primary function of a taper tap in a set of three taps (taper, second, bottoming)?

    A. To form threads that are tapered along their entire length.
    B. To produce a very fine thread pitch.
    C. To begin the thread-cutting process in an untapped hole.

    Correct Answer: C. To begin the thread-cutting process in an untapped hole.
    Explanation: A taper tap has a significant lead-in taper (6-8 threads) that allows it to start cutting a new thread easily and accurately in an unthreaded hole. It is always the first tap used in the sequence.

 


13. For which of the following measurement tasks is a Dial Test Indicator (DTI) most suitable?

    A. Confirming a dimension to within a tolerance of 0.125 inches.
    B. Measuring the absolute depth of a blind hole.
    C. Checking a cylindrical bar for concentricity or bending.

    Correct Answer: C. Checking a cylindrical bar for concentricity or bending.
    Explanation: A Dial Test Indicator is a precision instrument designed to measure small deviations and variations. It excels at comparative measurements, such as checking for run-out, alignment, concentricity (bow) of a shaft, or surface flatness.

 


14. Which statement accurately describes the correct selection of a hacksaw blade for cutting different materials?

    A. A coarse-toothed blade should be used for cutting thin mild steel plate.
    B. A fine-toothed blade is appropriate for cutting through a thick aluminum block.
    C. A fine-toothed blade should be used for cutting thin metal sheet.

    Correct Answer: C. A fine-toothed blade should be used for cutting thin metal sheet.
    Explanation: When cutting thin material, it is crucial to have at least two or three teeth in contact with the material at all times. Using a coarse blade on thin sheet metal would cause the teeth to straddle the work, leading to snagging and blade breakage. A fine-toothed blade ensures a smooth, controlled cut.

 


15. In an AC circuit, a power meter reads 4 kW. A voltmeter reads 400 V and an ammeter reads 20 A. What is the Power Factor of the circuit?

    A. 0.5
    B. 2
    C. 20

    Correct Answer: A. 0.5
    Explanation: Power Factor (PF) is the ratio of True Power (kW) to Apparent Power (kVA). Apparent Power = Voltage × Current = 400 V × 20 A = 8000 VA or 8 kVA. True Power = 4 kW. Therefore, PowerFactor=TruePower/ApparentPower=4kW/8kVA=0.5.

 


16. When using an ohmmeter to test a circuit, what reading would signify an open circuit?

    A. A negative resistance value.
    B. A reading of zero resistance.
    C. A reading of infinite resistance.

    Correct Answer: C.A reading of infinite resistance.
    Explanation: An open circuit means there is a complete break in the path for current to flow. An ohmmeter measures resistance, and an infinitely high resistance indicates that the circuit is open.

 


17. How is torque loading correctly calculated?

    A. By multiplying the tangential force applied by its distance from the bolt’s axis.
    B. By multiplying the tangential force by the diameter of the bolt.
    C. By multiplying the tangential force by the distance it has moved.

    Correct Answer: A. By multiplying the tangential force applied by its distance from the bolt’s axis.
    Explanation: Torque is a measure of rotational force. It is defined as the force applied multiplied by the perpendicular distance (lever arm) from the point of force application to the center of rotation (the axis of the bolt).

 


18. Which of these fundamental electrical measurement devices requires its own internal power source to function?

    A. An ohmmeter.
    B. A voltmeter.
    C. An ammeter.

    Correct Answer: A. An ohmmeter.
    Explanation: An ohmmeter works by passing a small, known current from its own internal battery through the component being tested and then measuring the resulting voltage drop to calculate the resistance. Voltmeters and ammeters derive power from the circuit they are measuring.

 


19. When a digital multimeter is set to measure AC voltage or current, what value does the display typically show?

    A. The RMS (Root Mean Square) value.
    B. The peak value of the waveform.
    C. The average value of the waveform.

    Correct Answer: A. The RMS (Root Mean Square) value.
    Explanation: The RMS value of an AC waveform is its effective value, representing the equivalent DC value that would produce the same amount of heat. It is the standard value used for AC measurements unless specified otherwise.

 


20. What specific application are three-point micrometers, also known as bore micrometers, designed for?

    A. Measuring linear dimensions between two parallel surfaces.
    B. Accurately measuring external diameters.
    C. Accurately measuring internal diameters.

    Correct Answer: C. Accurately measuring internal diameters.
    Explanation: Three-point micrometers are specialized tools for measuring the inside diameter of holes (bores). Their three anvils make self-centering contact with the internal surface, providing a highly accurate measurement.