AET Study Guide 2026

Everything you need to pass the AET exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.

📋 AET Exam Format at a Glance

90
Questions
120 min
Time Limit
73%
Passing Score

📚 AET Topics to Study (37)

✍️ Sample AET Questions & Answers

1. How many discrete digital output values can a 12-bit ADC produce?
4,096

A 12-bit ADC can represent 2^12 = 4,096 discrete digital values, ranging from 0 to 4,095.

2. When an AET completes an avionics repair, the return-to-service entry must be signed by a person holding which certificate?
Airframe and Powerplant Mechanic or Repairman

Only an FAA-certificated Airframe and Powerplant (A&P) mechanic, Repairman, or authorized repair station representative may approve an aircraft for return to service after maintenance.

3. Which of the following correctly describes 'Safety Wire' (safetying) application on avionics rack mounting hardware?
Wire is threaded so that rotation of the fastener in the loosening direction tightens the wire

Safety wire must be installed so that the fastener cannot rotate in the loosening direction without pulling the wire taut, providing positive locking.

4. Why is it important to regularly calibrate test equipment used in aircraft maintenance?
To ensure the equipment provides accurate and reliable measurements

Regular calibration of test equipment is essential in aircraft maintenance to guarantee that all measurements taken are consistently accurate and reliable. Uncalibrated equipment can provide erroneous readings, leading to misdiagnosis of issues or incorrect adjustments, which could compromise aircraft safety and operational integrity. Calibration ensures that the tools perform within specified tolerances, maintaining the highest standards of precision.

5. What is the typical voltage output of an aircraft's 28V DC bus system when fully regulated?
27.5–28.5 volts

A regulated 28V system operates between approximately 27.5 and 28.5 volts to properly charge 24V batteries while powering the aircraft's electrical loads.

6. Which organization is primarily responsible for setting aviation safety regulations in the United States?
Federal Aviation Administration (FAA)

The Federal Aviation Administration (FAA) is the primary governmental authority responsible for regulating all aspects of civil aviation in the United States. Its mission includes ensuring the safety of air travel by setting and enforcing aviation safety regulations and standards.

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1. Learn with Flashcards → 2. Drill Practice Tests → 3. Take the Full Exam Simulation