Airframe vs Powerplant: what each A&P rating covers
Powerplant had the lowest written pass rate of the three mechanic tests in 2025: 63%.
Free. Built from the FAA test standards and test data. Every number cites its source.
On this page
What is the difference between Airframe and Powerplant?
Airframe covers the aircraft itself: structure, flight controls, landing gear, hydraulics, fuel, electrical and the other systems. Powerplant covers engines and propellers: piston and turbine engines, ignition, fuel metering, oil, exhaust and props. Each rating lets you sign off work, and do 100-hour inspections, in its own area. [FAA-S-ACS-1, Sections II and III, p. 4] [14 CFR Part 65, § 65.85, § 65.87]
Together they make the A&P: A for Airframe, P for Powerplant. Both start with the same General test.
| Topic | Airframe | Powerplant |
|---|---|---|
| What it covers | The aircraft's structure and systems | Engines and propellers |
| What you can sign off | An airframe and its related parts | A powerplant or propeller and its related parts |
| 100-hour inspection | On the airframe | On the powerplant or propeller |
| Written test | 100 questions, 2 hours, 70 to pass | 100 questions, 2 hours, 70 to pass |
| Subjects on the written | 15 | 13 |
| Written tests taken in 2025 | 16,885 | 17,572 |
| Written pass rate, 2025 | 74.01% | 63.04% |
| Average written score, 2025 | 75.90% | 72.58% |
| Experience for this rating alone | 18 months | 18 months |
Sources: [14 CFR Part 65, § 65.77, § 65.85, § 65.87] [FAA-G-ACS-1, Ch. 3, p. 12 to 14] [FAA-AKT-VOL-CY2025, CY2025, p. 1]
Neither rating lets you approve a major repair or major alteration for return to service. A mechanic with an Inspection Authorization (IA) can. [14 CFR Part 65, § 65.85(a), § 65.87(a), § 65.95]
Which is harder, Airframe or Powerplant?
Powerplant, going by the FAA's numbers. In 2025, 63.04% of people passed the Powerplant written, against 74.01% for Airframe and 69.59% for the General. Powerplant also had the lowest average score of the three. If you are short on study time, give Powerplant the most of it. [FAA-AKT-VOL-CY2025, CY2025, p. 1]
Airframe has its own trap. The single most-missed item on any mechanic written is an Airframe one: special inspections (AM.II.D.K5), missed 79.53% of the time from July 2024 to June 2025. [FAA-FMC-CY2025-Q2, 2nd quarter CY25, p. 1] Special inspections are the checks after something out of the ordinary, like a hard or overweight landing, severe turbulence, a lightning strike or a bird strike. [FAA-H-8083-30B, Ch. 10, Special Inspections, p. 10-12]
The FAA also reports school graduates separately, using a different measure. Graduates who tested within 60 days passed Airframe 87.7% of the time and Powerplant 85.6%. That count includes the oral and practical, and retests inside the 60 days, so don't compare it straight across with the numbers above. [FAA-AMTS-PASS-CY2024-Q4, Detail pass rate by exam code, p. 2 to 17]
What is on the Airframe written?
The Airframe written has 100 questions across 15 subjects. Most subjects are 5% to 10% of the test. Two can reach 15%: metallic structures and airframe inspection. Here is the FAA's own breakdown. [FAA-G-ACS-1, Written Test Blueprints, AMA, p. 13 to 14]
| Airframe subject | Share of questions |
|---|---|
| Metallic structures | 5 to 15% |
| Non-metallic structures | 5 to 10% |
| Flight controls | 5 to 10% |
| Airframe inspection | 5 to 15% |
| Landing gear systems | 5 to 10% |
| Hydraulic and pneumatic systems | 5 to 10% |
| Environmental systems | 5 to 10% |
| Aircraft instrument systems | 5 to 10% |
| Communication, light signals and runway lighting | 5 to 10% |
| Aircraft fuel systems | 5 to 10% |
| Aircraft electrical systems | 5 to 10% |
| Ice and rain control systems | 5 to 10% |
| Airframe fire protection systems | 5 to 10% |
| Rotorcraft fundamentals | 5 to 10% |
| Water and waste systems | 5 to 10% |
What is on the Powerplant written?
The Powerplant written has 100 questions across 13 subjects. Reciprocating engines and engine electrical systems can each reach 15% of the test. The rest are 5% to 10% each. [FAA-G-ACS-1, Written Test Blueprints, AMP, p. 14]
| Powerplant subject | Share of questions |
|---|---|
| Reciprocating engines | 5 to 15% |
| Turbine engines | 5 to 10% |
| Engine inspection | 5 to 10% |
| Engine instrument systems | 5 to 10% |
| Engine fire protection systems | 5 to 10% |
| Engine electrical systems | 5 to 15% |
| Engine lubrication systems | 5 to 10% |
| Ignition and starting systems | 5 to 10% |
| Engine fuel and fuel metering systems | 5 to 10% |
| Reciprocating engine induction and cooling | 5 to 10% |
| Turbine engine air systems | 5 to 10% |
| Engine exhaust and reverser systems | 5 to 10% |
| Propellers | 5 to 10% |
Should you get Airframe, Powerplant, or both?
If you can, aim for both. On the experience route, 30 months working on both at the same time qualifies you for both ratings. Earning them one after the other takes 18 months each. Both ratings are also required before you can work toward an Inspection Authorization. [14 CFR Part 65, § 65.77(b), § 65.91(c)]
| Your plan | Experience you need | Written tests you pass |
|---|---|---|
| Airframe only | 18 months on airframes | General and Airframe |
| Powerplant only | 18 months on powerplants | General and Powerplant |
| Both at once | 30 months doing both | General, Airframe and Powerplant |
Sources: [14 CFR Part 65, § 65.77(b)] [FAA-G-ACS-1, Ch. 3, p. 12]
One rating can still make sense. If your work is only on engines, or only on structures, start with the rating that matches it. You can add the other one later: you meet the experience rule for it and pass its tests within 24 months. [14 CFR Part 65, § 65.71(b)]
Going to school? A school can be rated for Airframe, Powerplant, or both, so check which before you enroll. [14 CFR Part 147, § 147.11] Read how to pick an aircraft mechanic school.
Where to start
Whichever rating you choose, the General written comes with it. Take the free A&P practice test to see where you stand: 20 General questions with the FAA source page on every answer. Not sure you qualify yet? Check if you're eligible for your A&P.
For the full process, read how to get your A&P license. For pay, see the aircraft mechanic salary guide.
Technical detailsShow
Privileges. § 65.85(a): a mechanic with an airframe rating may approve for return to service an airframe, or any related part or appliance, after performing, supervising or inspecting its maintenance or alteration (excluding major repairs and major alterations), and may perform the 100-hour inspection required by Part 91 on an airframe and approve it for return to service. § 65.87(a) gives the same for a powerplant or propeller. Paragraph (b) of each adds light-sport category privileges.
Written tests. FAA-G-ACS-1, Chapter 3: AMG 60 questions; AMA and AMP 100 questions each; blueprints give the percentage range per knowledge area. A school document or JSAMTCC certificate authorizes "general and airframe; general and powerplant; or general, airframe, and powerplant."
Pass rates. FAA Airman Knowledge Test volume report, CY2025: Airframe 16,885 tests, 74.01% pass, 75.90% average score; General 22,585, 69.59%, 74.02%; Powerplant 17,572, 63.04%, 72.58%.
Questions people ask
- Is Airframe or Powerplant harder?
- By pass rate, Powerplant. In 2025, 63.04% passed the Powerplant written and 74.01% passed the Airframe written. The average score was 72.58% on Powerplant and 75.90% on Airframe.
- Can you get just the Airframe or just the Powerplant rating?
- Yes. You need 18 months of experience for that one rating, or a school course for it. You pass the General written plus that rating's written, then the oral and practical.
- How many questions are on the Airframe and Powerplant written tests?
- 100 questions each. You get 2 hours per test and need a score of 70 to pass. The General written has 60 questions.
- Do you need both ratings for an Inspection Authorization?
- Yes. To apply for an IA, you must have held both the Airframe and Powerplant ratings for at least 3 years, among other rules.
Sources
Every fact above comes from one of these FAA or eCFR documents. Page numbers are the PDF page unless marked. The full list of what we use is on the sources page.
- 14 CFR Part 65: 14 CFR Part 65: Certification: Airmen Other Than Flight Crewmembers (eCFR current as of 2026-10-28)
- § 65.85 Airframe rating; additional privileges, p. 65.85
- § 65.87 Powerplant rating; additional privileges, p. 65.87
- § 65.71(b) Additional rating; § 65.77 Experience requirements, p. 65.77
- § 65.91(c) Inspection authorization eligibility; § 65.95 privileges, p. 65.91
- Chapter 10, Special Inspections, p. 10-12
- 14 CFR Part 147: 14 CFR Part 147: Aviation Maintenance Technician Schools (eCFR current as of 2026-10-28)
- § 147.11 Ratings, p. 147.11
- FAA-S-ACS-1: Aviation Mechanic General, Airframe, and Powerplant Airman Certification Standards (November 2021 (effective September 21, 2022))
- Table of contents, Sections II Airframe and III Powerplant, p. 4
- FAA-G-ACS-1: Airman Certification Standards Companion Guide for Aviation Mechanics (with Changes 1 and 2)
- Chapter 3, Written Test Description and test authorization documents, p. 12
- Chapter 3, Written Test Blueprints (AMA and AMP), p. 13
- Knowledge test volume, pass rate and average score, CY2025, p. 1
- FAA-FMC-CY2025-Q2: Frequently Missed Knowledge Test ACS Codes, 2nd Quarter CY25 (July 1, 2024 to June 30, 2025) (CY2025 Q2)
- Frequently missed ACS codes, 2nd quarter CY25, p. 1
- Detail pass rate by exam code, 8-1-2023 through 12-31-2024, p. 2 to 17