Practice Test Geeks(AM) Aircraft Maintenance Certification Practice Test
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Troubleshooting & Diagnostics Flashcards

7 cards from real AM practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Troubleshooting & Diagnostics flashcards as text

  1. A turboprop engine has a higher-than-normal torque reading for a given power lever position. What is the MOST likely explanation?

    Answer: Propeller pitch stuck in a lower blade angle than commanded

    Lower-than-commanded propeller blade angle increases drag on the propeller, causing the engine to develop more torque to maintain speed.

  2. A mechanic uses a megohmmeter (megger) to test aircraft wiring. A reading of 0 megohms between a wire and ground indicates:

    Answer: A direct short to ground (insulation failure)

    Zero megohms between a conductor and ground means the insulation has failed completely and the wire is shorted to the airframe.

  3. During engine start, a gas turbine engine lights off normally but then flames out before reaching idle. This is called a:

    Answer: False start

    A false start (also called a false light-off) occurs when the engine lights but cannot sustain combustion and flames out before reaching idle speed.

  4. An aircraft static system check reveals the altimeter reads 50 feet higher than field elevation when on the ground with correct baro set. The MOST likely cause is:

    Answer: A blocked or mislocated static port sensing higher-than-actual static pressure

    A static port in a high-pressure area (such as near an airflow disruption) reads higher pressure, which the altimeter interprets as lower altitude.

  5. Troubleshooting an electric fuel pump that runs but produces no fuel flow, the technician should first check:

    Answer: Fuel supply to the pump inlet and the pump outlet check valve

    A running pump producing no flow usually indicates either a dry inlet (no fuel supply) or a seized/stuck outlet check valve preventing fuel from passing.

  6. When using a borescope to inspect turbine blades, cracks that run perpendicular to the blade span are known as:

    Answer: Fatigue cracks (transverse cracks)

    Transverse (cross-grain) cracks perpendicular to the blade span are classic fatigue cracks caused by cyclic thermal and mechanical stress.

  7. A nose wheel steering system is sluggish in both directions and the hydraulic pressure is normal. What should be investigated?

    Answer: Steering actuator internal wear or restriction in the metering valve

    Sluggish steering with normal system pressure suggests the actuator has internal wear or the metering/control valve has a restriction reducing flow rate.