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 The FAA's Bill O'Brien on Owner Performed Maintenance

Please Note: Bill Retired from the FAA in Washington, DC, on December 31 of 2007. Sadly, he had medical difficulties in late 2008 and passed away on November 11, 2008.

Here is a clip from a blog on the AMT Magazine web site about Bill. You can see additional comments about Bill and his life at the link above.

The aviation maintenance has lost a true champion. Bill O’Brien was one of a kind. I knew Bill only on a casual basis. We never had the opportunity to do business together; however, whenever we were in each other’s company we chatted at length. I was always interested in what Bill had to say about whatever was the prevalent issue at the time. I found him to be always a gentleman, erudite, and a vocal proponent of the hangar-floor technician. I believe his life’s work was dedicated to finding ways to uplift the status of the aviation maintenance professional. He will be missed.

I believe Bill conferred a unique sense of pride to all aviation maintenance people he touched. Join us in eulogizing him by celebrating the good he did for our profession.

Courtesy of Bill’s son Mike you can enjoy some of the family’s photographs of Bill at


Article 105

FAA Feedback column

AMT Magazine

Big Deal!

Bill O’Brien


It was 8:46 am on a Tuesday morning two weeks ago. I was sequestered in my D.C. cubicle of power trying half-heartedly to tease some common sense out of some meaningless wall charts that were left over from the day before “brain storming session.” I was pondering an extraordinarily well thought out half-baked idea, when it happened, I got my first irate phone call of the day.

After the obligatory, “hello, how are you,” and we exchanged names, my caller told me that he was a GA mechanic who works in northern California. I immediately did the time zone math, and came up with 3 hours difference. Out of habit, honed by experience, I hastily picked up my pen and found some notepaper and was ready to copy because deep in my bones I knew this call was important.

How so? I will bet you a dollar to a donut that no mechanic in any time zone has ever, gotten up at 5:46 AM, just to call a bureaucrat in Washington and tell me what a fine job the FAA is doing. So I sat there, pen in hand, patiently waiting for the bomb to be dropped.

It wasn’t long in coming. “Mr. O’Brien?”---“I got a bone to pick with you.” He voiced his complaint in a slow, steady, low control voice that could only be uttered through clenched teeth. His issue was that the FAA was allowing pilots to work on their own airplanes at a GA airport that will remain nameless. He claimed a lot of this illegal work was done in the owner’s hangers on the weekends behind closed doors.

His main gripe was the work the pilots were doing was not only doing the preventive maintenance called out in appendix A of Part 43, but everything else including engine swaps, sheet metal work, radio and STC installations, or whatever else you can imagine. I told him that I would contact the local FSDO and ask them to step up the weekend surveillance work at the airport. Also, I told him I would recommend to the FSDO’s Aviation Safety Program manager that he give some Aviation Safety Programs on the privileges and limitations of pilot performed maintenance.

I told him if nothing positive happened in a month then he had the right to call me back and give me hell. He seemed satisfied with this telephone pact with a DC devil and we parted on good terms.

While I waited for the West Coast to go to work I began thinking about pilot performed maintenance. There are two major problems that are always occurring. The first problem is the pilot usually does not have the proper tools, the current data, or the expertise to do the job. The second problem is that pilots rarely make a maintenance entry in the aircraft’s log book even though it is required by the regulations. It always astounds me what lengths pilots will take, to save a buck.

Now pilot/owners reading this always will say what’s the Big Deal! “Is my airplane, its my hide on the line,” or “I know what I can do or not!” and “Why sign a log book and give the Feds the rope to hang me.” My response is: Regulations and workmanship aside, the Big Deal is what happens to the people you leave behind. When there is an accident, especially a fatal one, and maintenance is determined to be a factor, the FAA inspector performing the accident investigation always goes to the last entry in the log book. Many times the last entry was an Annual inspection, up to six or seven months prior to the accident. In addition the aircraft could have 50 to 60 additional hours on the Hobbs meter.

Now imagine if you will, you are working in your hangar and a Fed shows up, and he takes you aside and quietly tells you that an airplane you worked on six months ago has crashed, and three people are dead, including a nine year old boy. While that bit of horrifying news is slowly sinking in; the FAA inspector then asks you if he could see the work order for the aircraft in question.

Despite a well deserved reputation mechanics have for being stoic individuals in a very demanding career field, when the work order is handed over, no mechanic has ever failed to ask me in a low, strained voice, “Do you know what went wrong?” I usually can’t answer him right away. I heard his question just fine, but it’s his haunted eyes that steal my attention. Those eyes are screaming at me, “Did I make a mistake?” “Did I killed those people?”

Many times with the help of eyewitnesses, I garnered enough facts that indicate that the pilot did perform additional maintenance on the aircraft. But since the pilot never recorded anything in the logbook, we never know what work was actually done. So we have an unknown. Other times the investigation determined that the aircraft was operated for a considerable number of hours so the accident might be caused by an operational incident like a hard landing, high G loading, or damage caused by something as simple as hangar rash on a wing. So the triggering factor that caused maintenance related failure could have happened hours prior to the accident but again we are not sure, so we put it down as another unknown.

These are worst case accident scenarios, the unknowns. Its bad because the mechanic is left with the nagging doubt that he could have screwed up. He could have killed those people. He could have made that fatal mistake! He might be responsible! Mechanics, who experienced this ongoing nightmare, tell me that this cold feeling of “maybe it was my fault” never goes away. The worry lies just below the conscience level of thought, but always making its presence known by robbing oneself of inner peace. Other mechanics have told me the uncertainty is like an old nagging memory poorly hidden somewhere in the back of one’s mind. The lingering doubt becomes a dull, throbbing pain of conscience that slowly poisons old friendships and stifles new ones.


But even the deepest buried, scabbed over, nagging doubt can come roaring back into one’s life when the memory is trigged by a visual cue. It can happen as simply as looking over one’s shoulder and seeing a similar make and model aircraft as the fatal taxi up to the hangar door. These memory flashbacks gives a mechanic a small taste of hell, and hell, my friends, is a thing to avoid. And that is why Pilots, mechanics consider it a Big Deal that pilots who work on aircraft should follow the rules and record that work.

So in the interest of safety and my sworn duty to explain and defend the Federal Aviation Regulations I have developed this hand-out that explains to pilots what they can do and what they cannot do when they hold a wrench in their hand. All a mechanic has to do to become a partner with me in this pilot educational process is to hang this chart any where pilots gather, such as the airport restaurant, or pilot’s lounge. If you are up for a walk on the wild side perhaps you can hand this chart out at a FAA pilot’s safety meeting and answer maintenance questions at the same time. There is an outside chance that you might get verbally beat up a bit by an irate pilot but education is not a risk-free business.


Here is the definitive word on the regulations

that permits pilots to perform maintenance

For Aircraft Operated under Part 91 with a FAA Standard Airworthiness Certificate.

1. Private Pilots or higher are permitted by Part 43 (Maintenance, Preventive Maintenance, Rebuilding, and Alterations) section 43.3 (g) of the Federal Aviation Regulations to only perform “preventive” maintenance on any aircraft owned or operated by that pilot and not used under Part 121, 127, 129, and 135.

2. Part 1 defines “Preventive maintenance” as simple or minor preservation

operations and the replacement of small standard parts not involving complex

assembly operations.

3. Thirty-two Preventive maintenance job functions are identified in appendix A of

Part 43.

4. Pilots, like mechanics are required to be trained to perform the preventive maintenance tasks before accomplishing the tasks alone.

5. Private Pilots or higher are required by section 43.7 to approve an aircraft for

return to service after preventive maintenance is performed.

6. The approval for return to service log book entry for preventive maintenance must

have the following information to comply with section 43.9:

a. Date of the completion of the work

b. Description of the work performed

c. Data used to perform the work

d. Signature and certificate number of the Pilot approving the aircraft for return to service. Sample Entry follows:

Powerplant Log Book for Swiftfire 200 N2195T

November 30, 2000, Tach 2445.7 hours.

Drained oil and replaced with 8 qts of(name brand ). Removed oil filter and replaced with a new (name brand ) oil filter and safetied. Cleaned spark plugs and regapped and installed new spark plug gaskets. Spark plugs installed using recommended torque, Spark plug leads secured. All work done in accordance with current Swiftfire 200, and (name engine make and model) current maintenance and parts manuals, Operational run-up and leak check ok.

Patrick Poteen, Private Pilot

Certificate # 180359122


7. The pilots name and certificate number constitutes an “approval for return to

service statement” only for the preventive maintenance work performed. (ref:

section 43.9(a)(4).

8. The performance standard for quality of work the Pilot must meet is found in

section 43.13 Performance rules. The standards are:

a. Use the methods, techniques and practices found in the current manufacturer’s maintenance manual or instructions for continued


b. Use the recommended tools, equipment, and test equipment to accomplish

the work in accordance with standard industry practices.

c. If special tools are required to perform a task, then that tool or its equivalent must be used to accomplish that task.

d. The work preformed must be of such a quality, that the condition of the

part worked on is equal to the original or properly altered condition.

Note: The Pilot is required by section 21.303 to use replacement parts produced by the manufacturer, or parts produced under a Parts Manufacturer Approval, (PMA) or technical Standard Order, (TSO). The pilot can also use standard aviation parts such as aircraft hardware, safety wire, etc. Do not use automotive or marine parts because these are considered suspected-unapproved parts and once installed on your aircraft the airworthiness certificate may not be valid.

Note: There is one other rule in Part 43 that is argumentatively the most important rule in the entire part. The rule is Section 43.12 Maintenance records, Falsification, Reproduction or Alteration. Paraphrasing the rule language, the rule prohibits any individual from making a fraudulent or intentionally false entry in any required aircraft maintenance record. The rule also prohibits the alteration or reproduction of aviation records for fraudulent purpose. If a pilot is found guilty of violating section 43.12 his pilot certificate can be suspended or revoked by the FAA.

Any questions? Please contact your nearest FSDO or call Bill O’Brien at 202 267-3796

Just a final word to those mechanics whose suffer from feelings of doubt similar to what I have just described: “Be at peace my friend.” On this ball of dust we are not granted the power to change the past, but we can influence the future. Talk to other mechanics, or friends, or clergy about what you feel, get it off your chest. I am sure, that just talking about it will help a lot.

But if you feel uncomfortable about talking about this to your friends or peers, give me a call. Just say when I pick up the phone that you want to talk about a Big Deal. I will not ask for your name or where you are calling from, but give me a second and I will put my FAA badge in the drawer, and from then on, it will be a conversation between two mechanics, who share a similar experience.