- The Magic Number: What Score Do You Actually Need?
- How PSI Scores the IRA Knowledge Test
- Which of the 8 Domains Decide Your Score
- What IRA Questions Actually Look Like
- Booking Through PSI: Cost, Age, and Authorization
- Eligibility You Need Locked In Before Test Day
- A Domain-Weighted Study Timeline
- After You Pass: The 24-Month Clock
- FAQ
- You need 70% on 60 scored questions to pass the IRA knowledge test.
- 5 additional unscored validation questions appear but don't count against you.
- You get 2 hours total, and the current PSI voucher costs $175 plus tax.
- FAA 2025 data show a 94.38% pass rate, so failing is avoidable with domain-specific prep.
The Magic Number: What Score Do You Actually Need?
The Instrument Rating - Airplane (IRA) knowledge test, administered by PSI on behalf of the FAA, requires a minimum score of 70% to pass. The exam consists of 60 scored multiple-choice questions plus 5 additional unscored "validation" questions that PSI uses to test future exam content. You won't know which questions are scored and which are validation items, so every question deserves your full attention. You'll have 2 hours to complete all 65 questions, which averages out to roughly 1.8 minutes per question - tight, but workable if you've trained on the material rather than trying to reason through it cold.
Passing at 70% means you can miss up to 18 of the 60 scored questions and still walk away with a passing report. That sounds forgiving, but the IRA test doesn't distribute those 60 questions evenly across easy and hard topics - some domains, like instrument approach procedures and ATC clearances, tend to carry more weight and more nuance. Missing 18 questions concentrated in two or three weak domains is a very different outcome than missing 18 scattered randomly.
How PSI Scores the IRA Knowledge Test
PSI delivers the IRA test on computer, and your score report is generated immediately after you submit. The report shows your overall percentage and typically flags the subject areas (mapped to the ACS domains) where you missed the most questions - useful diagnostic data if you need to retest, but not something you should rely on as your primary study plan. FAA-S-ACS-8C, effective May 31, 2024, is the current Airman Certification Standards document governing what's testable, and it's organized by the same domain structure used on the exam itself.
Because the test only reports category-level performance rather than question-by-question feedback, you can't reverse-engineer exactly which fact you missed. That's why building domain-level command of the material - not just memorizing answer patterns - is the only reliable path to a comfortable margin above 70%. For a full walkthrough of how to structure that kind of preparation, the IRA Study Guide 2026: How to Pass on Your First Attempt breaks down a first-attempt strategy in more depth than we can cover here.
Which of the 8 Domains Decide Your Score
The IRA knowledge test draws its 60 scored questions from eight ACS domains. Understanding what each domain actually covers - not just its title - is the difference between a comfortable pass and a nail-biter.
Domain 1: Preflight Preparation
Weather sources, NOTAMs, alternate airport minimums, and IFR flight planning fall here. Expect questions that require you to interpret weather products, not just define terms.
- Alternate minimums and the 1-2-3 rule
- Interpreting METARs, TAFs, and area forecasts
Domain 3: ATC Clearances and Procedures
This domain tests your ability to read back and comply with clearances, understand holding instructions, and apply lost-communications procedures - a heavily tested area on the actual PSI exam.
- Clearance void times and hold-for-release instructions
- Lost communication procedures (route, altitude, timing)
Domain 6: Instrument Approach Procedures
Reading approach plates, identifying minimums, and understanding missed approach procedures make this one of the densest domains on the test.
- Circling approach categories and visibility minimums
- Stepdown fixes and required visual references
The remaining domains - Preflight Procedures, Flight by Reference to Instruments, Navigation Systems, Emergency Operations, and Postflight Procedures - round out the exam and each contribute their own share of scored questions. For a category-by-category breakdown of exactly what's testable in each, see the IRA Exam Domains 2026: Complete Guide to All 8 Content Areas, which maps every domain to the ACS in detail.
Key Takeaway
Don't study domains equally just because there are eight of them. ATC clearances, approach procedures, and navigation systems tend to be denser and more heavily tested than postflight procedures - allocate study time accordingly.
What IRA Questions Actually Look Like
Every question on the IRA knowledge test is multiple-choice with three answer options. Many questions require you to reference a figure - an approach plate excerpt, a chart segment, or an instrument panel illustration - rather than answering from memorized text alone. This is a key reason generic multiple-choice test strategies fall short: you need to be fluent in reading real IFR charts and instrument depictions under time pressure, not just recognizing keywords.
A large share of missed questions on this exam come not from not knowing the regulation, but from misreading a chart detail or applying the wrong minimum to the wrong approach category. If you want a realistic sense of how the exam actually feels day-of, How Hard Is the IRA Exam? Complete Difficulty Guide 2026 covers the specific traps candidates report most often.
Booking Through PSI: Cost, Age, and Authorization
Registration for the IRA knowledge test runs through PSI. As of now, the FAA test voucher costs $175 plus applicable tax. That fee covers a single sitting; if you fail and need to retest, you'll pay the fee again along with meeting PSI's retest waiting requirements.
Two eligibility gates apply before PSI will let you sit for the test:
- Minimum age: You must be at least 15 years old.
- Test authorization: For an initial attempt, you need either an FAA-approved pilot-school graduation certificate or statement of accomplishment, or an endorsement from an authorized instructor confirming you're prepared for the test.
Without one of these authorizations, PSI will not allow you to schedule the exam, so confirm your endorsement or graduation paperwork before you book a testing slot. For a full cost picture that includes training and the practical test on top of the knowledge test fee, check the IRA Certification Cost 2026: Complete Pricing Breakdown. If you're mapping out when to schedule your test relative to your training timeline, IRA Exam Dates 2026: Testing Windows, Deadlines & Scheduling covers how PSI availability and your 24-month validity window interact.
Eligibility You Need Locked In Before Test Day
Passing the knowledge test is only one requirement in the full instrument rating pathway. Before you're eligible for the associated practical test, you also need:
- A current private pilot certificate, or a concurrent application for one.
- 50 hours of cross-country pilot-in-command time, including at least 10 hours in airplanes.
- 40 hours of actual or simulated instrument time, including at least 15 hours of instrument training with an authorized instrument-airplane instructor.
None of these hours requirements are enforced at the knowledge-test stage, but PSI's authorization rule (the pilot-school certificate or instructor endorsement) is a proxy check that you're on track. A full walkthrough of every eligibility item, including how the hour requirements interact with the knowledge test timing, is in IRA Requirements 2026: Eligibility, Prerequisites & How to Qualify.
A Domain-Weighted Study Timeline
Rather than studying the eight domains in the order they appear in the ACS, weight your schedule toward the domains with the most tested content and the most figure-reading questions - approach procedures, ATC clearances, and navigation systems.
Foundations
- Preflight Preparation: weather products, NOTAMs, alternate minimums
- Preflight Procedures: aircraft systems and airworthiness for IFR flight
Clearances and Instrument Flying
- ATC Clearances and Procedures: readbacks, holds, lost comm
- Flight by Reference to Instruments: attitude instrument flying, unusual attitude recovery
Navigation and Approaches
- Navigation Systems: GPS, VOR, ILS interpretation
- Instrument Approach Procedures: plate reading, minimums, missed approaches
Emergencies, Postflight, and Full Reviews
- Emergency Operations and Postflight Procedures
- Full-length timed practice tests under real 2-hour conditions
This is a scheduling framework, not a substitute for content mastery - the actual depth you need in each domain is covered in the IRA Exam Domains 2026: Complete Guide to All 8 Content Areas. Running full-length timed sets on our IRA practice test platform during week four is one of the most direct ways to simulate the real 60-question, 2-hour format before you commit to a PSI appointment.
After You Pass: The 24-Month Clock
Once you clear the 70% threshold, your result doesn't expire immediately - but it isn't indefinite either. The FAA requires that your knowledge-test result be used within the 24 calendar months preceding your practical test. If you let that window close without completing your checkride, you'll need to retake the knowledge test before you can move forward.
Given that FAA calendar-year 2025 data show a 94.38% pass rate on this exam, most candidates who prepare using domain-focused material clear it comfortably on the first attempt. If you want to see how that pass rate breaks down and what it implies about difficulty, IRA Pass Rate 2026: What the Data Shows covers the numbers in more detail. And if you're weighing whether pursuing the rating is worth the time and cost at all, Is the IRA Certification Worth It? Complete ROI Analysis 2026 and the IRA Salary Guide 2026: Complete Earnings Analysis lay out the broader career case.
Key Takeaway
Don't treat the 24-month validity window as a distant deadline. Schedule your practical test milestones early so knowledge-test material - especially approach procedures and clearance phraseology - stays fresh going into the checkride.
FAQ
You need at least 70% correct on the 60 scored multiple-choice questions. Five additional unscored validation questions appear on the test but do not count toward your score.
PSI's current FAA test voucher price is $175 plus applicable tax. This fee applies each time you sit for the test, including retests.
You have 2 hours to complete 60 scored questions plus 5 unscored validation questions, for 65 total multiple-choice questions.
Yes. For an initial attempt, PSI requires either an FAA pilot-school graduation certificate or statement of accomplishment, or an endorsement from an authorized instructor confirming your readiness.
Your knowledge-test result must be used within the 24 calendar months preceding your practical test. After that window closes, you'll need to retest.
Preparing domain by domain, and rehearsing the real question format on a full-length IRA practice test before your PSI appointment, is the most direct route to clearing the 70% threshold with room to spare. For a quick final review before test day, the IRA Cheat Sheet 2026: One-Page Review of Must-Know Facts condenses the highest-yield facts across all eight domains into a single reference.