The PHAK, short for the Pilot’s Handbook of Aeronautical Knowledge, is the FAA’s core textbook for pilot training, covering aerodynamics, aircraft systems, weather, airspace, navigation, and aeromedical factors. The current edition is FAA-H-8083-25C (2023), and the FAA treats its October 2025 addendum as part of that edition, so you need both; each is a free PDF from faa.gov. This guide walks through all 17 chapters, shows where each one appears in the ACS, and explains how to study it for the knowledge test and checkride.
Part of our Learn to Fly guide. The PHAK is the textbook behind the Airman Certification Standards and the private pilot written exam, so keep those guides open as you read.
What the PHAK is and who it is for
The FAA’s Flight Standards Service publishes the PHAK as the basic knowledge reference for pilots, and its preface says it serves beginners as well as pilots pursuing advanced certificates. The ACS bears that out: the PHAK is a reference for every Task in the Private Pilot and Commercial Pilot airplane ACS and for 15 of the 22 Tasks in the Instrument Rating airplane ACS. If you are working toward your private pilot license, you will use it from your first lesson through your checkride.
It lines up closely with the knowledge areas a private pilot applicant must be trained on under 14 CFR 61.105(b), from aerodynamics and weight and balance to weather and decision-making. The gap is the rules themselves: the preface says the handbook presents most certification knowledge areas except the Code of Federal Regulations, and it calls familiarity with 14 CFR and the Aeronautical Information Manual (AIM) essential. That is why the PHAK and a current FAR/AIM belong together.
The PHAK is guidance, not regulation. Its preface says its occasional use of “must” is not intended to add to, interpret, or relieve any duty imposed by 14 CFR. The ACS, by contrast, is incorporated by reference into 14 CFR part 61. The ACS sets the standard you are tested against, and the PHAK teaches it.
The current edition: FAA-H-8083-25C plus the 2025 addendum
As of October 2026, the FAA’s handbook page lists FAA-H-8083-25C as the current PHAK. Its cover is dated 2023, and it replaced FAA-H-8083-25B (2016) along with three interim addenda issued from 2021 to 2023. The FAA described 25C as a minor revision and said a major revision was underway; that rewrite has not been published yet.
On October 20, 2025, the FAA issued a five-page PHAK addendum for the MOSAIC rule, whose sport pilot certification changes took effect October 22, 2025. The FAA states that the addendum is part of the current edition until the next revision of FAA-H-8083-25 is published. It updates sport pilot privileges and limitations, medical qualification wording, and light-sport aircraft material in Chapters 1, 3, 6, 9, and 17. The changes matter most if you are training for a sport pilot certificate, but read it either way so your book matches current rules.
To check what you have:
- Check the cover. It should read FAA-H-8083-25C, dated 2023. Replace a 25B (2016) or older copy; the FAA’s knowledge test guidance tells applicants to answer according to current regulations and guidance publications.
- Add the addendum. Print it or save it next to your PDF so it stays with the book.
Where to get the PHAK: free PDF or print
The official source is the FAA’s Pilot’s Handbook of Aeronautical Knowledge page. Download the full handbook as one PDF (about 78 MB) or each chapter, the appendices, the glossary, and the index separately; chapter files run from about 5 MB to 36 MB. The addendum is listed directly below the handbook on the FAA’s Aviation Handbooks and Manuals page.
Printed copies are typically reprints of the same FAA text by commercial publishers. The FAA notes that any reproduction of its handbook material is the publisher’s responsibility, so confirm that a printed copy’s cover reads FAA-H-8083-25C. You will find the printed PHAK with the rest of the private pilot training materials at PilotMall.com.
PHAK chapters at a glance
The handbook has 17 chapters, three appendices, a glossary, and an index. The last column shows where each chapter appears in the Private Pilot Airplane ACS (FAA-S-ACS-6C), the standard behind both the knowledge test and the checkride. For plain-English versions of the aircraft chapters, see our How Airplanes Work guide.
| Chapter | What it covers | Where it shows up in the ACS |
|---|---|---|
| 1. Introduction to Flying | The FAA’s role, aircraft classifications, pilot certificates and privileges, the student pilot, and the knowledge and practical tests | Task I.A, Pilot Qualifications |
| 2. Aeronautical Decision-Making | Risk management, hazardous attitudes and antidotes, the PAVE checklist, single-pilot resource management, and the DECIDE and 3P models | Task I.H, plus the risk management elements in every Task |
| 3. Aircraft Construction | Certification and airworthiness, major components, construction methods, and composites | Tasks I.B and I.G |
| 4. Principles of Flight | The atmosphere, pressure and density altitude, Newton and Bernoulli, and airfoil design | Task I.F, Performance and Limitations |
| 5. Aerodynamics of Flight | The four forces, wingtip vortices, ground effect, stability, turns, stalls, P-factor, and load factor | Task I.F, Task V.A (Steep Turns), and Area VII (Slow Flight and Stalls) |
| 6. Flight Controls | Primary controls, flaps, leading edge devices, spoilers, trim tabs, and autopilots | Task I.G, Operation of Systems |
| 7. Aircraft Systems | The engine and propeller, carburetor icing, fuel, ignition, oil, electrical, landing gear, oxygen, and ice protection | Task I.G and Task IX.C (Systems and Equipment Malfunctions) |
| 8. Flight Instruments | Pitot-static instruments and blockages, electronic displays, gyroscopic instruments, and compass errors | Task I.G and Area VIII (Basic Instrument Maneuvers) |
| 9. Flight Manuals and Other Documents | The ten sections of the POH, aircraft documents, inspections, inoperative equipment, preventive maintenance, and ADs | Task I.B, Airworthiness Requirements |
| 10. Weight and Balance | Weight and CG effects, key terms, and the computation, graph, and table methods for weight and balance | Task I.F |
| 11. Aircraft Performance | Climb and range performance, takeoff and landing performance, performance speeds, and reading performance charts | Task I.F and the takeoff and landing Tasks in Area IV |
| 12. Weather Theory | Pressure, wind, stability, moisture, fog, clouds, air masses, fronts, thunderstorms, and icing | Task I.C, Weather Information |
| 13. Aviation Weather Services | Briefings, METARs and TAFs, PIREPs, AIRMETs and SIGMETs, winds aloft, weather charts, and data link weather | Task I.C |
| 14. Airport Operations | Markings, signs, and lighting, traffic patterns, radio communications, transponders and ADS-B, wake turbulence, and runway incursion avoidance | Area III (Airport and Seaplane Base Operations) and Task XI.A (Night Operations) |
| 15. Airspace | Controlled and uncontrolled airspace classes, special use airspace, basic VFR weather minimums, and operating rules | Task I.E, National Airspace System |
| 16. Navigation | Sectional charts, variation and deviation, the wind triangle, flight computers, pilotage, dead reckoning, VOR, GPS, and lost procedures | Task I.D (Cross-Country Flight Planning) and Area VI (Navigation) |
| 17. Aeromedical Factors | Obtaining a medical certificate, hypoxia, spatial disorientation and illusions, carbon monoxide, fatigue, alcohol and drugs, and night vision | Task I.H (Human Factors) and Task XI.A |
Of the appendices, Appendix A has performance data for a Cessna 172R and a Challenger 605, Appendix B lists acronyms, abbreviations, and NOTAM contractions, and Appendix C covers airport signs and markings.
How to study the PHAK for the knowledge test and checkride
- Start from the ACS. Every Task in the Private Pilot Airplane ACS lists its references, and FAA-H-8083-25 appears in all 61 of them. Pick a Task, read the matching PHAK sections, then check yourself against that Task’s knowledge, risk management, and skill elements.
- Read what you need before solo first. Under 14 CFR 61.87(b), your instructor must give you a pre-solo knowledge test on applicable Part 61 and 91 rules, the airspace rules and procedures for the airport where you will solo, and your airplane’s flight characteristics and operating limitations. That makes Chapters 9, 14, and 15, plus your POH and the regulations, early priorities. Weather, performance, and navigation follow as you plan cross-countries.
- Let a course set the pace. The PHAK is a reference, not a syllabus. A ground school or test prep course sequences the material and drills the question styles, and the PHAK is where you go when an explanation does not click. Take full-length practice tests before you schedule the real one.
- Practice with the test figures. The PHAK stays home on test day. You work from the FAA testing supplement the proctor provides (FAA-CT-8080-2H for private pilot), and you may use a plotter and a flight computer such as an E6B. Practice reading its charts and legends as you study Chapters 11 and 16.
- Turn your test report into oral prep. Your Airman Knowledge Test Report lists an ACS code for each question you miss. Look up each code, reread the PHAK sections behind it, and review them with your instructor. The examiner reviews that report during the oral exam portion of your checkride and assesses those areas.
Weather products changed faster than the PHAK. Chapter 13 still teaches the text Area Forecast for the lower 48 states, but the FAA’s 2026 Aviation Weather Handbook says text Area Forecasts are retired outside Alaska, replaced by the Graphical Forecasts for Aviation (GFA) tool and related graphics. The ACS lists the GFA. Learn the theory from the PHAK and the current products from the Aviation Weather Handbook and our airspace and weather guide.
Companion FAA handbooks
The PHAK explains why airplanes and weather behave as they do. These FAA handbooks fill in the rest; each edition below was checked against the FAA’s handbook list in October 2026.
| Handbook | Current edition | What it adds |
|---|---|---|
| Airplane Flying Handbook | FAA-H-8083-3C (2021), plus an October 2025 addendum | How to fly the maneuvers, from basic flight through landings and emergencies. Listed with the PHAK in every private pilot ACS Task. |
| Risk Management Handbook | FAA-H-8083-2A (2022) | Practical tools for identifying hazards and assessing risk. Also referenced in every private pilot ACS Task. |
| Aviation Weather Handbook | FAA-H-8083-28B (April 2026) | In-depth weather theory and current weather products, including the GFA tool |
| Instrument Flying Handbook | FAA-H-8083-15B (2012), with an errata sheet and two addenda | Attitude instrument flying for the Basic Instrument Maneuvers Tasks, and a core reference for the instrument rating |
| Weight and Balance Handbook | FAA-H-8083-1B (2016), plus an October 2025 addendum | A deeper treatment of the weight and balance procedures in PHAK Chapter 10 |
Add a current FAR/AIM for the regulations and procedures the handbooks leave out.
Print, PDF, or tablet?
- PDF: free, current when downloaded from the FAA page, and text-searchable. The files are large, so download them over Wi-Fi.
- Print: easier to highlight, tab, and read cover to cover, and it never needs a charge. Check the edition, and tuck the addendum inside the cover.
- Tablet: keep the PHAK and Airplane Flying Handbook PDFs in one reader app for quick searches between lessons.
What you'll need
The printed PHAK, its flying companion, and the references and tools you will use beside it, from PilotMall.com.
Frequently asked questions
What does PHAK stand for?
PHAK stands for Pilot’s Handbook of Aeronautical Knowledge, the FAA handbook FAA-H-8083-25. It covers the core knowledge pilots need, including aerodynamics, aircraft systems, flight instruments, weather, airspace, navigation, and aeromedical factors.
What is the current edition of the PHAK?
As of October 2026, the current edition is FAA-H-8083-25C, dated 2023, together with the FAA addendum dated October 20, 2025. The FAA considers that addendum part of the current edition until the next revision is published.
Is the PHAK free to download?
Yes. The FAA posts the full handbook and each chapter as free PDF files on its Pilot’s Handbook of Aeronautical Knowledge page. Printed copies are publisher reprints of the FAA text, so check that the cover shows FAA-H-8083-25C.
Is the PHAK enough to pass the private pilot written exam?
It covers most of the knowledge areas, but not the regulations themselves. Study it with the FAR/AIM, the Private Pilot ACS, and a ground school or test prep course, and practice with the figures in the FAA testing supplement.
Can I bring the PHAK into the knowledge test?
No. The FAA’s ACS Companion Guide lists handwritten, printed, and electronic written materials as unacceptable. You use the supplement book the proctor provides, plus allowed aids such as a plotter and a flight computer.
Is the Airplane Flying Handbook the same as the PHAK?
No. The PHAK (FAA-H-8083-25C) explains aerodynamics, systems, weather, airspace, and navigation, while the Airplane Flying Handbook (FAA-H-8083-3C) explains how to fly the maneuvers. Both are listed as references for every Task in the Private Pilot Airplane ACS.