- Exam Snapshot: Fees, Format, Timing
- The 12 ACS Domains at a Glance
- Regulations and Numbers You Cannot Miss
- Performance, Weight & Balance, and Aerodynamics Fast Facts
- Weather and Navigation Shorthand
- Airspace and Airport Ops Quick Reference
- Aeromedical and ADM in One Breath
- Final-Week Review Schedule
- Validity, Retesting, and What Happens After
- FAQ
- The CAX has 100 scored questions plus 5 unscored ones, 105 total, in 2 hours 30 minutes.
- You need 70% to pass; the 2025 pass rate was 99.17% across 20,530 tests.
- The test fee through PSI Services LLC is $175 plus applicable tax.
- Part 61 airplane applicants generally need 250 flight hours before certification.
Exam Snapshot: Fees, Format, Timing
Before you memorize a single V-speed or weight-and-balance formula, lock in the mechanics of the test itself. The FAA's Commercial Pilot Airplane knowledge test, abbreviated CAX, is administered through PSI Services LLC at approved testing centers. Here's the one-page version of what you're walking into:
| Item | Detail |
|---|---|
| Test name | Commercial Pilot Airplane (CAX) |
| Administered by | PSI Services LLC |
| Fee | $175 plus applicable tax |
| Question count | 100 scored + 5 unscored validation = 105 total |
| Time allowed | 2 hours 30 minutes |
| Passing score | 70% |
| 2025 pass rate | 99.17% across 20,530 tests |
| Minimum age to test | 16, with ground-school completion or instructor endorsement |
| Current standard | FAA-S-ACS-7B, effective May 31, 2024 |
Those five unscored questions are folded in without labeling, so treat every question on screen as if it counts - you won't know which ones are being validated for future test banks. For a deeper breakdown of how the exact passing threshold is calculated, see CPL Passing Score 2026: Exactly What You Need to Pass.
The 12 ACS Domains at a Glance
Everything on the CAX traces back to twelve content areas defined in the FAA-S-ACS-7B standard. Print this list and check off each one as you feel confident:
- Federal Aviation Regulations
- Aerodynamics and Principles of Flight
- Aircraft Systems and Flight Instruments
- Weight and Balance
- Aircraft Performance and Limitations
- Weather Theory
- Weather Reports and Forecasts
- Navigation and Flight Planning
- Airspace Classes and Requirements
- Airport Operations and Procedures
- Aeromedical Factors
- Aeronautical Decision Making
If you want the full explanation of what each domain actually tests - sample question phrasing, weighting patterns, and study order - the CPL Exam Domains 2026: Complete Guide to All 12 Content Areas goes far deeper than a cheat sheet can. This page is designed to be your rapid-fire recall tool, not your primary study resource.
Regulations and Numbers You Cannot Miss
Domain 1: Federal Aviation Regulations
Part 61 and Part 91 questions dominate this domain. You must know eligibility mechanics cold, not just from memory but well enough to apply them to scenario questions.
- Knowledge-test applicants must be at least 16 years old and hold an accepted ground-school completion document or instructor endorsement.
- Certificate issuance requires age 18, English proficiency, at least a private pilot certificate, required endorsements, aeronautical experience, and a passed practical test.
- Part 61 airplane applicants generally need 250 flight hours total.
- A passing knowledge-test report is generally valid for 24 calendar months before the practical test.
Regulation questions on the CAX are rarely asked as "what does 61.129 say" - they're framed as scenarios. Expect a question describing a pilot's logbook entries and asking whether they meet the aeronautical experience requirement, or a scenario about currency and medical validity that tests whether you understand how flight-review, recency, and medical requirements continue to apply even after certification. The regulation isn't memorized in isolation; it's applied to a story.
Key Takeaway
Don't just memorize the 250-hour figure - know the sub-requirements (cross-country time, night time, instrument time) that make up that total, since scenario questions test the components, not just the headline number.
Performance, Weight & Balance, and Aerodynamics Fast Facts
Domains 2, 3, 4, and 5 are the calculation-heavy cluster of the exam. These are the questions where a cheat sheet mindset backfires if you don't actually understand the underlying physics - the CAX likes to change one variable (altitude, temperature, load) and ask you to predict the effect.
Domain 2: Aerodynamics and Principles of Flight
Focus on load factor in turns, stall speed relationships, and how bank angle changes the stall margin.
- Stall speed increases with the square root of the load factor
- Steeper banks require proportionally more lift and increase stall speed
- Adverse yaw and its correction remain testable concepts
Domain 4: Weight and Balance
You'll be handed a loading scenario and asked to compute CG location, then determine if it falls within limits.
- Practice both the computational and graph-based methods
- Know how shifting cargo or fuel burn moves CG in flight
- Understand forward vs. aft CG effects on stall speed and stability
Domain 5: Aircraft Performance and Limitations
Density altitude is the recurring theme - high, hot, and humid conditions degrade performance, and the exam wants you to quantify that using charts.
- Practice reading takeoff and landing distance charts under varying conditions
- Know how pressure altitude and temperature combine into density altitude
- Understand the performance penalty of a heavier gross weight on climb rate
These are also the domains where difficulty complaints tend to concentrate. If you're wondering whether this section of the test is genuinely harder than the private pilot exam, How Hard Is the CPL Exam? Complete Difficulty Guide 2026 breaks down exactly where the jump in complexity happens.
Weather and Navigation Shorthand
Domains 6, 7, and 8 form a connected chain: understand weather theory, read weather products, then apply both to a flight-planning problem. The CAX loves cross-referencing a METAR or TAF against a cross-country planning scenario.
- Weather Theory: stability, frontal behavior, icing conditions, and thunderstorm structure
- Weather Reports and Forecasts: decoding METAR, TAF, winds aloft, and convective outlook products
- Navigation and Flight Planning: pilotage, dead reckoning, VOR/GPS navigation, and fuel/time/distance calculations under changing wind components
A common trap: candidates memorize METAR decoding in isolation and then get tripped up when a question pairs that METAR with a performance question - for example, using reported temperature and altimeter setting to compute density altitude for a takeoff distance problem. Treat these three domains as one continuous skill, not three separate topics.
Airspace and Airport Ops Quick Reference
Domain 9 and Domain 10 test practical, visual knowledge - sectional chart symbols, airspace dimensions, and radio/lighting procedures at towered and non-towered fields.
Domain 9: Airspace Classes and Requirements
Know the vertical and lateral dimensions, entry requirements, and equipment requirements for each class.
- Class B, C, and D entry and communication requirements
- Class E floor variations and how they're depicted on charts
- Special use airspace symbols and restrictions
Domain 10: Airport Operations and Procedures
Expect scenario questions about traffic pattern entry, runway markings, and lighting systems.
- Standard pattern entry and non-towered field communication procedures
- Runway incursion avoidance and hold-short line meaning
- PAPI/VASI interpretation and runway lighting configurations
Aeromedical and ADM in One Breath
Domains 11 and 12 are often underestimated because they feel less technical, but they carry real weight on the exam. Aeromedical Factors covers hypoxia, hyperventilation, spatial disorientation, and the physiological effects of altitude and fatigue. Aeronautical Decision Making tests judgment through scenario-based questions - there's rarely a single "textbook" answer; instead you're choosing the safest, most conservative option among plausible choices.
- Know the symptoms and altitude thresholds associated with hypoxia and know the difference between hypoxic, hypemic, stagnant, and histotoxic hypoxia
- Understand the illusions that cause spatial disorientation during instrument-limited flight
- For ADM scenarios, always favor the answer that reduces risk exposure over the one that saves time
Remember too that passing the knowledge test is only one gate. Exercising commercial pilot privileges after certification still depends on flight-review currency, recency of experience, and a valid medical - the ADM domain often tests whether you understand that these obligations don't end at the checkride.
Final-Week Review Schedule
If your test date is close, don't try to relearn everything - triage. Here's a compressed final stretch built around the domains most likely to need last-minute reinforcement based on where CPL candidates typically lose points.
Performance & Weight and Balance
- Redo every chart-reading problem type: takeoff distance, climb performance, CG computation
- Time yourself - these calculations eat clock time on test day
Weather + Navigation Chain
- Decode 10 METAR/TAF samples cold, then feed results into a cross-country planning problem
- Review wind correction angle and groundspeed calculations
Regulations + Airspace
- Drill Part 61 aeronautical experience scenarios
- Re-memorize airspace dimensions and entry requirements
Light Review + Aeromedical/ADM
- Skim aeromedical symptom lists once
- Read a handful of ADM scenarios to re-calibrate "choose the safest option" instinct
- Avoid cramming new material the night before
For a full walk-through of how to structure study time from day one rather than just the final week, see the CPL Study Guide 2026: How to Pass on Your First Attempt.
Validity, Retesting, and What Happens After
Once you pass, your knowledge-test report is generally valid for 24 calendar months before your practical test - don't let it lapse while you're still building flight hours. Plan your 250-hour timeline and checkride scheduling with that window in mind.
It's also worth stepping back and asking why you're doing this. The certificate opens doors to charter, aerial work, flight instruction, and airline-track flying, and understanding what those paths actually pay and demand helps frame your prep. See CPL Jobs and CPL Salary Guide 2026: Complete Earnings Analysis for the career side, and Is the CPL Certification Worth It? Complete ROI Analysis 2026 if you're still weighing the investment. If you're earlier in the process and unsure whether you even meet the baseline eligibility, back up to CPL Requirements 2026: Eligibility, Prerequisites & How to Qualify before diving into domain-level prep.
Key Takeaway
Treat this cheat sheet as a pre-test refresher, not a substitute for structured practice. Run full-length timed simulations on our CPL practice test platform to convert this recall list into exam-day speed.
FAQ
The CAX contains 100 scored multiple-choice questions plus 5 unscored validation questions, for 105 total, with 2 hours 30 minutes allowed to complete them.
You need 70% on the scored questions. See CPL Passing Score 2026: Exactly What You Need to Pass for how that threshold is applied.
The fee is $175 plus applicable tax, paid through PSI Services LLC, the FAA's contracted test administrator. This covers only the knowledge test, not flight training or checkride costs.
A passing knowledge-test report is generally valid for 24 calendar months before you must complete the practical test.
The 2025 pass rate was 99.17% across 20,530 tests, suggesting most well-prepared candidates pass, though several domains involve dense calculations. See CPL Pass Rate 2026: What the Data Shows and How Hard Is the CPL Exam? Complete Difficulty Guide 2026 for more context.
This cheat sheet condenses the numbers, domains, and regulatory thresholds you're most likely to need at a glance, but real exam readiness comes from repetition. Run timed question sets on cplpracticetest.com against each of the 12 domains until the recall becomes automatic.