Is Your Aircraft Okay to Fly?

Who decides whether or not your aircraft is airworthy?

Airworthy steampEarlier this year, I wrote an article titled “Fix It Now…Or Fix It Later” that was published in a major general aviation magazine. The article discussed how to deal with aircraft mechanical problems that arise during trips away from home base. It offered specific advice about how pilots and aircraft owners can decide whether a particular aircraft issue needs to be addressed before further flight or whether it can safely wait until the aircraft gets back home. I considered the advice I offered in this article to be non-controversial and commonsense.

I was surprised when I received an angry 700-word email from a very experienced A&P/IA—I’ll call him “Damian” (not his real name)—condemning my article and accusing me of professional malfeasance in advising owners to act irresponsibly and violate various FARs. Damian’s critique started out like this:

After reading Mike Busch’s commentary “Fix It Now … Or Fix It Later,” I must take exception to most, if not all, the points made in his column. I believe his statements are misleading as to the operation of certified aircraft, to the point of being irresponsible for an A&P to suggest or imply that it’s up to the owner/operator whether or not to fly an aircraft with a known discrepancy. The FARs are quite clear on this matter, and there have been numerous certificate action levied on pilots who have operated aircraft with known discrepancies.

Damian went on to state that the FARs require that any aircraft discrepancy, no matter how minor, must be corrected and the aircraft approved for return to service “by persons authorized under FAR 43.7 (typically the holder of a mechanic certificate).” He went on to explain that the owner/operator may only approve for return to service those preventive maintenance items listed in FAR Part 43 Appendix A. He went on:

It should be noted that the FAA does not take into consideration the inconvenience or cost related to addressing a known discrepancy. Nor is it up to the owner/operator to determine the significance of a discrepancy as the FARs do not confer this discretion privilege to the owner/operator.

Damian’s attack on my article continued at great length, making it quite clear that his believe is that pilots and aircraft owners are mere “appliance operators” in the eyes of the FAA, and that only certificated mechanics are empowered to evaluate the airworthiness of an aircraft and determine whether or not it is legal and safe to fly. He ended his diatribe by saying:

I hope that others in the aviation community such as FAA Airworthiness Safety Inspectorss and aviation legal professionals weigh in on this commentary. I believe all will agree that this commentary is misleading and uninformed to the point of being irresponsible even to publish. At the very least, pilots that follows the advice of Busch’s commentary should enroll in the AOPA Pilot Protection Services plan because they’re likely to need it!

Whew! Strong stuff! If Damian is right, then the FAA had better lock me up and throw away the key. Fortunately for me, I believe he isn’t and (at least so far) they haven’t.

Where Damian Has It Wrong

Damian and I do agree on at least one thing: FAR 91.7 does indeed say quite unequivocally that it is a violation to fly an unairworthy aircraft, and that if the aircraft becomes unairworthy in flight, the PIC is obligated to discontinue the flight. I would never suggest for a moment that any pilot fly a known-unairworthy aircraft, at least without a ferry permit. That’s a no-brainer.

The much more difficult question is: Exactly how does the PIC decide whether or not an aircraft is airworthy or unairworthy, and therefore whether he is or isn’t allowed to fly it? On this question, Damian and I part company. In fact, his view and mine seem to be diametrically opposite.

Damian’s view is that almost any aircraft discrepancy requires the involvement of an A&P mechanic to evaluate and clear the discrepancy and approve the aircraft for return to service. I see absolutely nothing in the FARs to support such a position, particularly when it comes to non-commercial aircraft operated under Part 91.

To begin with, the basic airworthiness rule (FAR 91.7) is crystal clear about who is responsible for determining whether or not the aircraft may be flown. It says:

The pilot in command of a civil aircraft is responsible for determining whether that aircraft is in condition for safe flight.

The regulation places the burden squarely on the shoulders of the PIC. I don’t see anything there about A&Ps or repair stations having to be involved, do you?

Looking a bit deeper into the FARs, I can find only three circumstances under which a mechanic is required to get involved in making any sort of airworthiness determination on a Part 91 aircraft used for non-commercial purposes:

  1. Exactly once a year, FAR 91.409 requires that an annual inspection be performed by an A&P/IA or a Repair Station. But the other 364 days of the year, it’s the PIC who determines whether the aircraft is airworthy.
  2. When an Airworthiness Directive or Airworthiness Limitation becomes due, FAR 91.403 requires that a mechanic must certify that the AD or AL has been complied with (with rare exceptions where the PIC may do so).
  3. When an owner actually hires a mechanic to perform maintenance on an aircraft, in which case the mechanic is required to document his work and sign it off to testify that the work was performed properly. Note, however, that the mechanic’s signature in the logbook entry does NOT signify that the aircraft is airworthy, only that THE WORK PERFORMED by the mechanic was done in an airworthy fashion.

This third point is one that is frequently misunderstood by mechanics and owners alike. When I teach this stuff at IA renewal seminars, the hypothetical example I often use to illustrate this important point involves an owner who takes his aircraft to a mechanic for repair. The mechanic immediately observes that the aircraft has two obvious discrepancies: the right main landing gear tire is flat, and the left wing is missing. The owner asks the mechanic to fix the flat tire. The mechanic does so, makes a logbook entry describing the work he did on the right main landing gear, and signs it. His signature denotes only that the work he did (fixing the flat tire) was done properly. When the owner picks up the aircraft, the mechanic tells the owner, “I couldn’t help but notice that your left wing is missing. If you’ll permit me to offer you a word of friendly advice, I would not attempt to fly the aircraft until that issue is resolved.” But the missing left wing does not prevent the mechanic from signing the logbook entry. In fact, the mechanic is required by regulation to sign the logbook entry, regardless of whether the aircraft is airworthy or not. The mechanic’s signature addresses only the work performed by the mechanic, and nothing else.

The PIC’s Burden

If you’re on a trip and some aircraft discrepancy occurs – assuming the aircraft isn’t in the midst of its annual inspection and there’s no AD involved – it is up to you as PIC to determine whether or not that discrepancy makes the aircraft unairworthy or not. If you decide that it does, then you can’t fly the airplane until the airworthiness issue is rectified (and that might require hiring an A&P). On the other hand, if you decide that the discrepancy doesn’t rise to the level of making the aircraft unairworthy, then you’re free to fly home and deal with the issue later.

Under the FARs, it’s totally the PIC’s call. There’s no regulatory obligation for the PIC to consult a mechanic when making such airworthiness determinations. Having said that, however, it would certainly be a wise thing to do if you feel uncomfortable about making the decision yourself. It’s your call.

The FARs provide considerable help to the PIC in making such airworthiness determinations. FAR 91.213(d) describes a specific algorithm for deciding whether or not it’s okay to fly an airplane with various items of inoperative equipment. FAR 91.207 says that it’s okay to fly an aircraft with an inoperative ELT to a place where it can be repaired or replaced, no ferry permit required. FAR 91.209 says that position lights needn’t be working if you’re flying during daylight hours. And so on.

If your experience is anything like mine, what most of us call “squawks” are common occurrences, but the majority of them don’t rise to the level of being airworthiness items that cause us (in our capacity as PIC) to conclude that a fix is required before further flight. Even if you do encounter a genuine airworthiness problem – say a flat tire or dead battery or bad mag drop – that still doesn’t mean that you necessarily need to get a mechanic involved. The FARs provide (in Part 43 Appendix A) a list of roughly three dozen items that a pilot-rated owner or operator is permitted to perform and sign off on his own recognizance (without getting an A&P involved).

If you have a flat tire, for example, you (as a pilot-rated owner) are permitted to repair or replace it yourself. If you have a dead battery, you can charge it, service it, or even replace it. If you have a bad mag drop, the most common cause is a defective or fouled spark plug, and you’re permitted to remove, clean, gap, and replace spark plugs yourself. You are also allowed to make repairs and patches to fairings, cowlings, fabric (on fabric-covered aircraft), upholstery and interior furnishings. You can replace side windows, seat belts, hoses, fuel lines, landing and position lamps, filters, seats, safety wire, cotter pins, and more. You can even remove and install tray-mounted avionics from your panel.

Now, you might well prefer to hire an A&P to do some of these things rather than do them yourself, especially when on the road, far from your hangar and toolbox. I know I certainly would, and I’m an A&P myself. But Damian’s contention that you are compelled by the FARs to place your aircraft in the hands of an A&P any time any sort of discrepancy arises is simply not supported by the regulations.

Contrary to what Damian and many of his A&P colleagues may believe, the FAR’s place the responsibility for determining the airworthiness of the aircraft squarely on the PIC, except for once a year when an IA is required to make an airworthiness determination after performing an annual inspection

My colleague Mac McClellan pointed out to me that this closely resembles how the FAA determines whether a pilot is “airworthy.” One day every year or two or five, we pilots are required by regulation to go get an examination from an Aviation Medical Examiner who pronounces us medically fit to fly, or not. The remaining 364 or 729 or 1,824 days in between, the FAA expects us to self-certify that we’re medically fit. “Can you imagine,” Mac asked me rhetorically, “if we had to go to see an AME every time we got a sore throat or runny nose?”

Mike Busch is arguably the best-known A&P/IA in general aviation, honored by the FAA in 2008 as National Aviation Maintenance Technician of the Year. Mike is a 8,000-hour pilot and CFI, an aircraft owner for 50 years, a prolific aviation author, co-founder of AVweb, and presently heads a team of world-class GA maintenance experts at Savvy Aviation. Mike writes a monthly Savvy Maintenance column in AOPA PILOT magazine, and his book Manifesto: A Revolutionary Approach to General Aviation Maintenance is available from in paperback and Kindle versions (112 pages). His second book titled Mike Busch on Engines was released on May 15, 2018, and is available from in paperback and Kindle versions. (508 pages).


  1. Mike55_Mahoney

    July 24, 2015 at 11:30 am

    saved in my library.

    • These rules apply to anyone operating any registered vehicle in the air, on the road and in the water. The driver of an automobile, wether they are the owner or not, is responsible for it’s condition to be safely operated on the road. A bad auto accident happened in my community years ago where a dump truck had known poor breaks. The driver could not stop for a red light. The driver was found negligent for operating the vehicle with a known safety issue.

  2. It’s amazing how the regulations make sense… when they’re applied in a common sense fashion. I just renewed my medical yesterday; I’m so glad we don’t have to go through that every time we fly.

  3. Robert Q. Steinman, A&P, PhD

    July 24, 2015 at 6:41 pm

    It sounds like Damian is only interested in feathering his nest, much like an IA I know who says that after an annual, even after an A&P signs off a squawk, the owner needs to bring the A/C back to him for his approval before the A/C Annual is complete (at an additional cost).

  4. Even Damien says “there have been numerous certificate actions levied on pilots”. That implies the FAA holds the pilot accountable, not the mechanic. I have never heard of a mechanic being held responsible for the general airworthiness of an aircraft (only the repairs made by the mechanic). The decision to fly lies with the pilot, as do the consequences of that decision. If, as Damien implies, pilots are incapable of deciding what is airworthy, then why do we waste all that time doing those pre-flight checks?

  5. As usual Mike, you nailed it. (Sorry Damian.) Used to have a similar discussion with some of our pilots in the military. Problem was solved when we showed their bosses the plane was airworthy. (One in particular didn’t like flying B-47’s and would ground the aircraft for every imaginable thing he could.)

  6. While in the middle of nowhere Alaska, landed and found that the fabric on our sea fin was torn. Decided to buy a role of 200 mph duct tape to do a temporary fix. Later, landed in Juneau and had the fin replaced. As PIC, I conclude that the plane was airworthy and I guarantee that there was no A&P on or within 50 miles of that island.

  7. I also know that the most dangerous time to fly any airplane is immediately after an annual or repair. One flying club with which I used to fly had a really nice Cessna 140. I got checked out in it just before it went into an annual. A week later, my instructor, while checking out another pilot in the plane had an emergency. While doing touch and goes on a long field in CA, the elevator locked in an up position. She used power adjustments to descend and to soften the landing. Still balled up the plane, but they got out with few injuries. Turned out the A&P/IA had left a screwdriver in the tail and it jammed the bell crank. He’d signed the annual. It would have been nearly impossible for the pilots to discover this.

  8. After my aircraft is in any shop I will go over the work as I am fussy and its my butt up there, and most time I will find a screw missing or 2, a connection that moves, wires touching where they may rub. I trust my shop but we all know that after coffee we sometimes assume the task is complete!

  9. Some time ago an article described an incident where a pilot on a business trip had a flat at a fuel stop. He asked the FBO to replace the tire while he went to lunch. On returning he discovered his plane still on jacks. He was informed that the brake disc thickness was some few thousandths under limits and the aircraft was unairworthy until the disc was replaced. To start with there is no requirement to conduct a dimensional inspection of the brake disc or any other part of the landing gear when replacing a tire – – and there was no urgency to replace the disc before further flight. Another example of the too prevalent practice of fleecing a captive aircraft owner!

  10. About this brake disc example: if the disc is removed to replace a tire, which it is in most cases, can the mechanic legally reinstall it knowing it is not up to specs and still sign off the work (tire change) he is responsible for?

    • fdsfkdsfidsifidsii

      July 31, 2015 at 8:05 pm

      I think the A&P would likely refuse to finish the work without dealing with the disc in any case. He has no responsibility to sign off on incomplete work. Most A&Ps seem to want to stay very clear of any potential issues with the FAA regardless of whether the FARs appear to be on their side or not. Most just want to play it safe and you can’t really fault them for that. My guess is that they’d be doing the right thing anyway because the FAA will find their own technicality to bust them on. It doesn’t matter what the FARs say, the only thing that matters is what the judge says.

  11. It sounds like “Damian” is referencing this precedent by the FAA, in which the resulting certificate action certainly infers that you MUST seek A&P attention to resolve any discrepancy, no matter how minor.

    • fdsfkdsfidsifidsii

      July 31, 2015 at 7:57 pm

      I didn’t see a link to the actual ruling, but it seems that the crux of the issue was that the judge didn’t believe that the pilot conducted a thorough inspection. Perhaps the timeline of events would not have left enough time for the pilot to conduct a thorough inspection or perhaps the pilot’s description of the damage did not match with the actual repairs made. In either case I don’t think this ruling implies that any discrepancy requires A&P attention

  12. Kurt Malerich

    July 31, 2015 at 6:35 pm

    Mike,,, Thanks, your are right (as usual) on this subject. Sounds like Damian the Draconian is all about control and generating invoices for himself. The bulk of the responsibility for determining airworthiness (outside of an Annual Inspection) lies squarely on the shoulders of the owner/operator. By Damian’s standards we would all be required to hire an A&P prior to every flight to determine airworthiness. Sorry Damian, but you are out to lunch. KMalerich. A&P/IA

  13. Mike, I’m not here to defend Damian, I didn’t get to read all 700 words, however FAR 91.213 says nothing about an ELT or flying it to a place where it can be fixed, unless you are just
    “paraphrasing.” I believe it’s important to note that while the PIC has the final authority to determine that the aircraft is in condition safe for its intended flight, it must be noted that
    the term “Airworthy” is at minimum a “two pronged animal.” One is; the aircraft is in condition safe for operation, and the other is; the aircraft meets is originally type certificated or
    properly modified condition. Those two items together make an airworthy aircraft. But I’m sure you knew that.
    There are a few variations of what is written on the airworthiness certificate, but the basics are the “terms and Conditions” of that certificate and its effectively, i.e. as long as the maintenance,
    preventative maintenance and alterations are performed IAW with FAR 21, 43 and
    91 of the FARs.
    That being said, the FAA has given the industry the 91.213 rule, provided you have an MEL, or, if you do not have an MEL, 91.213 goes on to say; (I’m “paraphrasing) you can
    still operate the aircraft with inoperative instruments or equipment. However, you must follow the rule and I have posted it from para (d) below, which is what most of us use anyway.
    If there is a system that one of my customers does not want to fix, or can’t afford to fix, I suggest the following: If you qualify for para (d)(1) and (d)(2), we can use para (d)(3)(i) or (d)(3)(ii). We will make an appropriate logbook entry showing compliance with para (d)(3)(i) or (d)(3)(ii) and provide a placard. However, if you are on the road, and you qualify for 91.213, make sure you have some tape some paper for your required placard if you don’t need and A&P.

    If you are going to keep the system inop, it’s a good idea to make sure there is a logbook entry per FAR 91.405(c) and (d) at the next inspection stating that the system is still
    properly deactivated and placarded in accordance with FAR 91.213 and 43.11.

    FAR 91.405 excerpt below:
    Maintenance required.
    Each owner or operator of an aircraft–
    (c) Shall have any inoperative instrument or item of equipment, permitted to be inoperative by
    Sec. 91.213(d)(2) of this part, repaired, replaced, removed, or inspected at
    the next required inspection; and
    (d) When listed discrepancies include inoperative instruments or equipment, shall ensure
    that a placard has been installed as required by Sec. 43.11 of this chapter.

    FAR 91.213 excerpt below:
    (d) Except for operations conducted in accordance with paragraph (a) or (c) of this section, a person may takeoff an aircraft in operations conducted under this part with inoperative
    instruments and equipment without an approved Minimum Equipment List provided–
    (1) The flight operation is conducted in a–
    [(i) Rotorcraft, nonturbine-powered airplane, glider, or lighter-than-air aircraft,
    powered parachute, or weight-shift-control aircraft, for which a master minimum
    equipment list has not been developed; or]
    (ii) Small rotorcraft, nonturbine-powered small airplane, glider, or lighter-than-air aircraft for which a Master Minimum Equipment List has been developed; and
    (2) The inoperative instruments and equipment are not–
    (i) Part of the VFR-day type certification instruments and equipment prescribed in the
    applicable airworthiness regulations under which the aircraft was type certificated;
    (ii) Indicated as required on the aircraft’s equipment list, or on the Kinds of Operations Equipment List for the kind of flight operation being conducted;
    (iii) Required by Sec. 91.205 or any other rule of this part for the specific kind of flight operation being conducted; or
    (iv) Required to be operational by an airworthiness directive; and

    (3) The inoperative instruments and equipment are–
    (i) Removed from the aircraft, the cockpit control placarded, and the maintenance recorded in accordance with Sec. 43.9 of this chapter; or
    (ii) Deactivated and placarded “Inoperative.” If deactivation of the
    inoperative instrument or equipment involves maintenance, it must be
    accomplished and recorded in accordance with part 43 of this chapter; and

    (4) A determination is made by a pilot, who is certificated and appropriately rated
    under part 61 of this chapter, or by a person, who is certificated and
    appropriately rated to perform maintenance on the aircraft, that the
    inoperative instrument or equipment does not constitute a hazard to the
    aircraft. An aircraft with inoperative instruments or equipment as provided in
    paragraph (d) of this section is considered to be in a properly altered
    condition acceptable to the Administrator.

    (e) Notwithstanding any other provision of this section, an aircraft with
    inoperable instruments or equipment may be operated under a special flight
    permit issued in accordance with Secs. 21.197 and 21.199 of this chapter.

    Good day.

  14. These rules apply to anyone operating any registered vehicle in the air, on the road and in the water. The driver of an automobile, wether they are the owner or not, is responsible for it’s condition to be safely operated on the road. A bad auto accident happened in my community years ago where a dump truck had known poor breaks. The driver could not stop for a red light. The driver was found negligent for operating the vehicle with a known safety issue.

  15. Larry A&P AI ATP

    August 1, 2015 at 1:24 am

    Too bad you couldn’t expose this Damien guy, but understand with a private email. We just don’t need this kind of ignorance in our mechanics world.

    We’ve had a few Damien’s meet us at stops in the airline business and wanted to ground the plane for a screw missing. There was one in St. Louis that was notorious for this and earn the reputation. Fortunately there’s not a ton of bad mechanics out there… but there’s sure a shortage of good ones.

  16. Hi Mike,
    I have always felt a little smarter each time I read one of your articles, and while this was no exception, I was already in agreement with you before I read the article. I have, in the past, worked with another A&P/IA, with whom I had to argue, on more then one occasion, about how to deal with a transient aircraft in our care, and it’s return to service. Without specific memory of an actual scenario, the problem would go almost exactly like your flat tire and missing wing example. My colleagues position was that after we fixed the flat tire, His log entry was going to state that due to the missing wing, the aircraft was found to be Un-airworthy, or he wasn’t going to sign the log entry. I would point out that we were not hired to make an airworthiness determination and his position was that that didn’t matter. I tried to explain that grounding a customers aircraft away from home was not only not our responsibility, it would be completely antagonistic, and probably insure that this particular owner/operator would never visit our facility ever again. This colleague, being of strong convictions, would force me to log the work myself, which I thought would be perfectly legal, since he was (even though he was licensed) working under my supervision, and I had inspected the work and found it to be satisfactory. On other occasions, I simply tossed his log entry (produced on a sticker as is so common now) in to the garbage and produced an entry of my own just to avoid the argument. I believe he tagged me as irresponsible and dangerous and eventually left our shop an excepted work elsewhere. I obviously stood my ground, and I do not believe I have ever endangered a pilot by not signing off work I had completed, and then stating the aircraft was Un-airworthy outside the case of an Annual Inspection where that was the whole purpose of the work.
    On another note, I recently failed to notice a ding in the rudder during a “Pre-purchase” inspection. When the seller came to pick up his aircraft, guess what, he says we damaged his aircraft and has sent us an estimate for thousands to complete the repair. I should have looked closer before the aircraft ever came in to the shop, a huge mistake on my part. I had been trying to adopt the better approach to prepurchase inspections where we would check the engine first for example, and then continue if that portion of the inspection was excepted by the prospective buyer. I had stopped at that point because there was insufficient log book evidence to support a time since overhaul claim in the logs. Now lawyers are involved, and our insurance company has stated that there is no such thing as a “prepurchase inspection” because it involves a mechanics opinion, which means this work would not be covered. Oh brother! Another small fact of which I should have been aware. Even as I try to stay informed and up to date, it seems that the likelihood of someone trying to take advantage of a shop is on the increase. I have always tried to produce quality work at a reasonable price and have accepted responsibility for any errors I may have committed….and what do you get?HEARTACHE. After more than 37 years, I’m beginning to think I have outlived my usefulness as an aviation maintenance technician. In any event, thanks for sharing your knowledge and experience.

    • I hate pre-buy inspections. We don’t use that term here. We use the following: Either the Customer gives us a check list and we call it “customer directed maintenance or inspection items” or if he doesn’t know anything, we say that we are going to evaluate the aircraft to determine its “worthiness” to be “eligible” for an Annual Inspection by Hangar One. If I wouldn’t annual it, you shouldn’t buy it. We start by giving him 5 hrs of evaluation time.

  17. Hi Mike:

    I am working as avionics Inspector for Bolivian CAA for several years and I’d would like to comment about this article from a total personal point of view. I coudn’t read the original article: “Fix It Now…Or Fix It Later”, so my opinion is just about what you wrote in this new one.

    I am sure you understand well the definition of airworthiness and the fact that “the aircraft is in condition for safe flight” is neccesary but not enought (sufficient). Must also be in conformity with the Type Certificate. In my opinion that analys is missing. I suggest to see this presentation:

    When you say: “The PIC is responsible for determining whether that aircraft is in condition for safe flight”, is not the same to say “the PIC is responsible for determining the airworthiness of the aircraft” nor “the PIC is responsible for the airworthiness of the aircraft”. The latter is true, but in order to make airworthiness determinations you need technical know-how.

    Aldo Escobar

  18. Interesting post . I was fascinated by the points ! Does anyone know where my company would be able to find a sample Acord 25 copy to type on ?

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