What you may legally do to your own aeroplane

Who this applies to

§ 43.3(g): the holder of a pilot certificate issued under Part 61 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.

Three things follow that catch people out. You need to be a certificated pilot. A mechanic's ticket is not what authorises this, and neither is simply owning the aeroplane. You need to own or operate the specific aircraft. And the moment it is flown under 121, 129 or 135, this authorisation stops applying to it, whoever you are.

§ 43.7(f) then lets a pilot holding at least a private certificate approve that aircraft for return to service after the preventive maintenance they performed. Note the scope: after the work you did, not for anything else.

What counts

The list is Part 43, Appendix A paragraph (c). It runs to around thirty items and it is worth reading in full rather than from memory. It is one page. In broad strokes it covers servicing rather than repair: tyres, wheel bearings, lubrication, simple fabric patches, replacing safety wire and cotter keys, servicing landing gear shock struts, replacing seats and safety belts, side windows, bulbs and reflectors, replacing or cleaning spark plugs, changing oil and filters, replacing batteries, prefabricated fuel lines, hose connections, and the like.

Treat that list as the boundary. The regulation's own words for paragraph (c) are "preventive maintenance is limited to the following work, provided it does not involve complex assembly operations." If what you want to do is not on the list, the answer this page gives you is to get an A&P involved.

Two honest complications

You will hear, correctly, that the FAA has itself read that list as illustrative rather than closed. In a 2009 legal interpretation (the Coleal letter) the Chief Counsel's office wrote that in view of the broader definition of preventive maintenance in § 1.1, the "limited to" language "is not controlling", and that the Appendix A lists "are better viewed as examples … they cannot be considered all-inclusive." FAA inspector guidance (Order 8900.1) repeats that position by name. It has never been withdrawn.

We still tell you to stay on the list, and the reason is not that the argument is weak. It is where the argument works. An FAA interpretation is a shield in an FAA enforcement action. An insurer denying a claim, a buyer walking away at pre-buy, or a plaintiff's lawyer after an accident is in no forum bound by an interpretive letter, and every one of them can read "limited to the following work" for themselves. The downside is lopsided, so the conservative line costs you little and protects you where it actually matters.

The second complication runs the other way, and it is the one almost nobody mentions: the list is not a floor either. The same interpretation is explicit that a task on the list is not automatically preventive maintenance on every aircraft. Its example is that removing a tyre, listed at ¶(c)(1), is not preventive maintenance a pilot may do on a large transport aircraft. Whether a job is preventive maintenance is a judgement about this task on this aeroplane, not a lookup. If your aircraft is large, turbine, or unusual, the list alone will not answer the question.

The part people skip: the record

Preventive maintenance is maintenance, so § 43.9 applies and an entry is required. Work with no entry is, on paper, work that did not happen, and it is the pre-buy, the insurance claim and the next annual that find out.

Each entry needs:

• a description of the work, or a reference to acceptable data
• the date it was completed
• your name, if you are not the person approving the return to service
• your signature, certificate number, and the kind of certificate you hold (your pilot certificate, here)

The signature is the approval for return to service, and it approves only the work performed. Signing the oil change does not say anything about the aeroplane's airworthiness generally, and it is not an inspection.

Keep it in the maintenance record for the aircraft or the component. Ownership of that record follows the aircraft: under § 91.417 it is the owner's or operator's duty to keep it, and to hand it over when the aircraft sells.

What this is not

It is not an annual, a 100-hour, or any other inspection. It does not let you sign off anything an A&P or IA is required for. It does not extend to repairs or alterations, and if the work turns out to be a major repair or alteration, the bar goes up considerably: approved data, an authorised signature, and a Form 337.

If you have heard of Canada's owner-maintenance aircraft, that is a different thing wearing a similar name. It is a permanent reclassification of the aircraft, with consequences for its certificate and its resale value, and nothing on this page describes it.

Where magsboth fits

We do not tell you whether a job is preventive maintenance. That judgement is yours and your mechanic's, and a product that guessed it for you would be wrong on exactly the aircraft where it matters. What we do is hold the record: the entry, the date, who signed it and against what, the photographs if you took them, and the due list that says what is coming.

The one opinion we do have is the one on this page: the entry matters more than most owners think, and the cheapest moment to write it is while the cowling is still off.