The Legal Basis: 14 CFR 43.3(g)
The authority for owner-performed preventive maintenance comes from 14 CFR 43.3(g), which states that the holder of a pilot certificate may perform preventive maintenance on any aircraft owned or operated by that pilot, provided the aircraft is not used under Part 121, 129, or 135. This means Part 91 owner-operators — private pilots who own their aircraft — have limited maintenance authority.
The key word is "preventive." This is not a license to perform major repairs or alterations. Preventive maintenance is defined as simple or minor preservation operations and the replacement of small standard parts not involving complex assembly operations. The specific items are enumerated in Part 43, Appendix A, paragraph (c).
The authority is wider than ownership. 14 CFR 43.3(g) lets a part 61 pilot certificate holder perform preventive maintenance on any aircraft owned or operatedby that pilot — so a club, rental or partnership aircraft you operate qualifies even if your name is not on the title. If you are a co-owner, any co-owner who holds a pilot certificate may perform the work. Three limits come with it, in the same paragraph: the aircraft must not be used under part 121, 129 or 135; sport pilot certificate holders are carved out separately and may do this only on an aircraft issued a special airworthiness certificate in the light-sport category; and an aircraft you neither own nor operate still needs an A&P.
The 31 Approved Preventive Maintenance Items
Part 43, Appendix A, paragraph (c) lists the specific items that qualify as preventive maintenance. Here are the most commonly performed items by owner-operators:
Engine and fluids: Changing oil and oil filter (or screen). Replacing and servicing spark plugs (including cleaning, gapping, and rotation). Replenishing hydraulic fluid in the hydraulic reservoir. Servicing landing gear wheel bearings (cleaning, inspecting, and repacking).
Tires and wheels: Replacing tires. Servicing landing gear struts by adding oil, air, or both. Replacing elastic shock absorber cords on landing gear. Replacing defective safety wire or cotter pins.
Airframe: Applying preservative or protective material to components where no disassembly of any primary structure or operating system is involved. Making simple fabric patches not requiring rib stitching or the removal of structural parts or control surfaces. Refinishing decorative coating of fuselage, wing, and tail surfaces (excluding balanced control surfaces).
Electrical and avionics: Replacing prefabricated fuel lines. Replacing bulbs, reflectors, and lenses of position and landing lights. Replacing cowling not requiring removal of the propeller or disconnection of flight controls. Replacing or cleaning spark plug terminal connectors. Replacing batteries and checking fluid level and specific gravity.
Other items: Replacing safety belts and harnesses. Replacing seats or seat parts not involving disassembly of any primary structure. Troubleshooting and replacing broken landing light wiring circuits. Replacing and servicing ELT batteries. Replacing or adjusting non-structural standard fasteners.
Logbook Entry Requirements
Every preventive maintenance action performed by an owner-pilot must be documented in the aircraft maintenance records. 14 CFR 43.9 specifies the required content of each logbook entry:
Date of the maintenance action. This is the date the work was completed, not started. Description of work performed.Be specific: "Changed engine oil, drained and replaced with 8 quarts AeroShell W100, replaced oil filter P/N CH48110-1" is adequate. "Oil change" is not.
Signature and certificate number. Sign the entry with your name and pilot certificate number. This constitutes your return-to-service authorization for the preventive maintenance performed. You are certifying that the work was done correctly and the aircraft is approved for return to service.
Sloppy or missing logbook entries create airworthiness questions during annual inspections and can affect aircraft value. Treat every maintenance entry as a legal document — because it is. The entry should be clear enough that another mechanic or inspector can understand exactly what was done.
What Requires an A&P or IA
Anything not specifically listed in Appendix A, paragraph (c) requires a certificated airframe and powerplant (A&P) mechanic. Major repairs and major alterations additionally require an Inspection Authorization (IA) holder to approve the return to service.
Common tasks that owners often assume they can do but cannot: adjusting or replacing brake linings (the word "brake" does not appear anywhere in Appendix A; its only occurrence in part 43 is Appendix D's annual/100-hour inspection scope, "Brakes—for improper adjustment", which is an inspection item and not owner work), any work on propellers beyond cleaning and minor dressing, any work on flight control cables or systems, replacing exhaust components, any structural repair, and any work involving primary structure disassembly.
The annual inspection (required every 12 calendar months under 14 CFR 91.409) must be performed by an A&P with Inspection Authorization or an FAA-approved repair station. The 100-hour inspection (required for aircraft used for hire) may be performed by an A&P mechanic. Owner-pilots cannot perform inspections.
Both requirements have an exemption, and it is in the same section. §91.409(a) and (b) open with “except as provided in paragraph (c)”, and §91.409(c) excludes aircraft carrying a special flight permit, a current experimental airworthiness certificate, a special airworthiness certificate in the light-sport category, or a provisional certificate — as well as aircraft inspected under an approved program under part 125 or 135. An experimental owner is not exempt from inspection: the operating limitations require a condition inspection, which is a different requirement with a different signer.
When in doubt, consult your A&P mechanic. Performing maintenance beyond your authority is a violation of 14 CFR 43.3 and can result in FAA enforcement action against your pilot certificate. It also creates an airworthiness issue — the aircraft may not be legally airworthy after unauthorized maintenance.
Common Mistakes and Best Practices
Using incorrect parts: When replacing spark plugs, oil filters, tires, or other components, use only parts approved for your specific aircraft and engine. Check the Type Certificate Data Sheet (TCDS) and applicable Supplemental Type Certificates (STCs) for approved parts. Using unapproved parts renders the aircraft unairworthy.
Exceeding Appendix A authority: The most common violation is performing work that seems simple but is not on the approved list. Just because a task is mechanically straightforward does not make it legal for an owner to perform. Stick to the 31 items — no improvisation.
Inadequate logbook entries: As noted above, vague entries are a frequent issue. Document exactly what you did, what parts you used (including part numbers), what you replaced, and any relevant specifications (oil quantity, torque values, etc.).
Not following manufacturer procedures:Even for preventive maintenance items, follow the aircraft manufacturer's maintenance manual procedures. Changing oil? Follow the manual for drain procedure, filter installation torque, and oil quantity. The manufacturer's procedure is the standard of care.
Best practice:Develop a relationship with your A&P mechanic. Ask them to show you proper techniques for the preventive maintenance items you plan to perform. Many A&Ps are happy to mentor owner-pilots, and the knowledge you gain improves both safety and your understanding of your aircraft.