The CAET (Certified Aircraft Electronics Technician) exam launched in Fall 2025. It is the first industry-standard certification specifically designed for avionics technicians, and it is brand new. That means there is no established study culture around it yet. There are no senior techs at your shop who have been through it and can tell you what to expect. No well-worn study guides passed between coworkers.
This guide fills that gap. It gives you a structured, proven study strategy for passing the CAET on your first attempt. We cover the exam format, all 11 categories ranked by study priority, an 8-week study plan, and the five strategies that will make the biggest difference in your score.
Whether you are a military avionics technician transitioning to civilian work, a fresh hire at a Part 145 repair station, or a seasoned bench tech getting officially credentialed, this guide will show you exactly how to prepare.
Understanding the CAET Exam Format
Before you build a study plan, you need to understand what you are studying for. The CAET is a standardized multiple-choice exam administered remotely by the Unmanned Safety Institute (USI) on behalf of the Aircraft Electronics Association (AEA). You take it from home or from your workplace. There is no testing center involved.
The exam is closed-book and proctored. You cannot use reference materials, calculators, or notes during the test. Your webcam and screen are monitored throughout the session. The questions are practical and job-focused — they test what you would actually encounter on the bench, not abstract engineering theory.
Quick Facts: CAET Exam
The time pressure is real. You have less than 54 seconds per question. That means you cannot afford to get stuck on any single question. Flag it, move on, and come back at the end. The retake policy gives you three total attempts: a 24-hour wait between your first and second attempt, and a two-week wait between your second and third.
100 questions in 90 minutes = 54 seconds per question. Practice with a timer. If you have never taken a timed test in this format, the clock will surprise you.
The 11 CAET Exam Categories
The CAET covers 11 knowledge categories. Not all categories carry equal weight, and not all are equally difficult. Below is every category ranked by study priority based on real exam weight and candidate difficulty.
DC Fundamentals HIGH
Ohm's Law, Kirchhoff's Laws, series/parallel circuits, power calculations. This is the foundation for everything else on the exam. Start here.
AC Fundamentals HIGH
Transformers, impedance, power factor, inductance, capacitance, and AC power distribution. Build directly on your DC knowledge.
Solid-State Devices MEDIUM
Diodes, transistors, voltage regulators, and semiconductor fundamentals. The exam focuses on practical applications — what these components do in a circuit, not how to derive their physics.
Digital Electronics & Data Buses CRITICAL
ARINC 429, MIL-STD-1553, RS-232/422/485, AFDX, CAN bus, logic gates, and binary math. This category accounts for roughly 16% of the exam and is the #1 area where candidates fail. Do not skip this.
Technical Documentation & Regulations MEDIUM
FARs, ACs, IPC, CMM, wiring diagrams, ADs, and Service Bulletins. The exam tests your ability to use documentation, not memorize it word for word.
Wire & Harness Fabrication MEDIUM
Crimping, soldering, shielding, wire types, coax connectors, and IPC/WHMA workmanship standards. Practical hands-on knowledge that any bench tech will recognize.
Safety & Human Factors LOW-MEDIUM
ESD protection, FOD prevention, LOTO procedures, human error models, and CRM. Quick study category — mostly common sense for experienced technicians.
Aircraft Electrical Systems HIGH
Power distribution, bus bars, generators, batteries, circuit breakers, and electrical troubleshooting. This is core avionics infrastructure — where your fundamentals meet the aircraft.
Communication Systems MEDIUM-HIGH
VHF, HF, SATCOM, intercom, audio panels, and antenna systems. You need system-level understanding — how these systems connect and how to troubleshoot them.
Navigation Systems MEDIUM-HIGH
VOR, ILS, GPS/GNSS, RNAV, WAAS, and FMS basics. Know how these systems work together to provide navigation capability from en-route to approach.
Surveillance & Flight Instruments MEDIUM
Transponders, TCAS, ADS-B, EGPWS, weather radar, pitot-static, EFIS, and glass cockpit displays. The exam emphasizes modern surveillance systems and how they integrate.
Digital Data Buses is roughly 16% of the real CAET exam and the #1 area where candidates struggle. If you only have time to deep-dive on one extra topic, make it this one. ARINC 429 and MIL-STD-1553 questions alone can make or break your score.
The 8-Week Study Plan
This plan assumes you are studying part-time — roughly 1-2 hours per day or 8-12 hours per week. If you have avionics experience, the early weeks will move faster. If you are newer to the field, give yourself extra time on fundamentals and data buses.
The order matters. Fundamentals come first because everything else builds on them. Data buses get two weeks because they are the hardest and most heavily weighted. Systems week comes near the end so you can apply everything you have learned.
Adjust the timeline to your experience level. If you have been working avionics for years, you can compress Weeks 1-2 and spend more time on data buses and systems. If you are newer, consider extending the plan to 10-12 weeks and doubling your time on fundamentals.
5 Study Strategies That Actually Work
Studying more hours does not automatically mean better results. The way you study matters as much as how long you study. These five strategies are backed by learning science research and have been validated by technicians preparing for standardized certification exams.
Spaced Repetition Beats Cramming
Research shows spaced repetition increases knowledge retention by 41% compared to traditional re-reading. The concept is simple: review material at increasing intervals instead of cramming everything the night before. Use flashcards with an algorithm that spaces reviews based on how well you know each card. The material you struggle with shows up more often. The material you have mastered fades into longer intervals. Do not re-read your notes — force yourself to recall the answer first.
The spaced repetition method increases retention by 41% compared to traditional re-reading. Use flashcards with increasing intervals. Recall beats recognition every time.
Focus on Data Buses Early
Digital Data Buses is roughly 16% of the real exam and it is the #1 area where candidates struggle. ARINC 429, MIL-STD-1553, RS-232/422/485, AFDX, CAN bus — these protocols are not intuitive, and most technicians have not studied them formally. If you only have time for one extra topic beyond your baseline knowledge, make it data buses. Start early so the material has time to sink in through spaced repetition rather than last-minute cramming.
Practice Under Timed Conditions
Ninety minutes for 100 questions means less than 54 seconds per question. That is not a lot. The first time you take a practice test with a timer running, you will feel the pressure. That is exactly the point. Take practice tests with a real countdown. Flag questions you are unsure about and come back to them — do not burn three minutes on one question when there are 99 others. Train yourself to make a decision and move on. Exam-day nerves are real, and the only antidote is familiarity with the format.
Think Practical, Not Academic
Eighty percent of CAET questions test real-world job knowledge. The exam asks "What would you do on the bench?" not "Derive the formula." If you have worked on aircraft, trust your experience. The CAET is not an engineering exam. It does not test thyristor switching theory, op-amp gain calculations, or flip-flop state tables. It tests whether you can troubleshoot a comm system, read a wiring diagram, and identify the correct wire type for an application. Study like a technician, not like a student.
Study the Systems, Not Just the Components
The exam tests system-level thinking. Do not just know what a transponder does in isolation — know how it integrates with ADS-B, TCAS, and the antenna system. Understand how a VOR receiver feeds into an FMS and how that relates to RNAV. Think about how power flows from the generator through the bus to the avionics rack. The CAET rewards technicians who can see the big picture, not just identify individual components. When studying any topic, always ask: "What does this connect to?"
Common Mistakes to Avoid
Knowing what not to do is just as important as knowing what to do. These are the five most common study mistakes CAET candidates make — and every one of them is avoidable.
- Skipping Digital Data Buses. This is the single biggest mistake. Data buses account for roughly 16% of the exam, and they are the most unfamiliar topic for most technicians. Skipping them or skimming them is throwing away points.
- Over-studying academic theory. The CAET is 80% practical, 20% foundational. If you are spending time on op-amp gain calculations, flip-flop state tables, or thyristor switching theory, you are studying the wrong material. Focus on what you would encounter on the shop floor.
- Not practicing under timed conditions. Ninety minutes is tighter than you think. If you have never taken a practice test with a 90-minute countdown, the real exam will feel rushed and stressful. Simulate the real thing at least 2-3 times before exam day.
- Studying in order 1-11 without prioritizing weak areas. Going straight through the categories in numerical order feels organized but wastes time on topics you already know. Identify your weakest areas early using a practice test, then allocate your study time accordingly.
- Ignoring wiring diagrams and technical documentation. Some candidates treat the documentation category as an afterthought. But being able to read a wiring diagram, interpret a CMM, and navigate ADs and Service Bulletins is a core job skill that the exam tests directly.
Tools and Resources
You do not have to study from scratch. These resources cover the material you need, and each one approaches CAET prep from a different angle.
Ace Avionics Training
CAET prep with spaced repetition flashcards, interactive simulations, and coverage of all 11 exam categories. Built by working avionics technicians.
Free CAET Practice Test
40 real-world questions with domain scoring across all 11 categories. See where you stand before you start studying.
AEA Official CAET Prep Course
Approximately 150 hours of material covering all exam categories. The official preparation course from the organization that created the CAET.
CAET Exam Registration
Register for the CAET exam at aea.net/caet/. Check eligibility requirements and exam scheduling availability.
Use multiple resources. No single source covers everything perfectly. A combination of structured coursework, flashcard review, and practice testing under timed conditions gives you the best chance of passing on your first attempt.