An IA’s Notes on Recent Annuals

As a long-time IA and A & P mechanic and pilot I look at airplanes with a somewhat different eye than pilots. My purpose, whether it's actually inspecting an aircraft, flying one or writing about my experiences, is safety. Most certificated aircraft owners should know what the meaning of airworthy is and that there are two parts to the determination that an aircraft is airworthy at the time of an annual inspection.

The first part is that the aircraft meets its type certificate design as when it was originally produced or is properly altered with FAA approval such as an STC or field approval. The other part is that the aircraft (including experimental aircraft) must be in a condition for safe operation. These requirements must be met for me as an IA to sign off an aircraft as airworthy at the time an annual inspection is completed.

Owner cooperation during the annual inspection is important to me and I explain to them what I am looking for when inspecting a plane and when I find things wrong I discuss what is wrong or how it may impact safety. Sometimes there may be more than one way to make the condition safe so I go to sufficient detail to allow them to make an informed decision.

Many commercial shops don't have the time or resources to offer different ways to correct the discrepancies and simply come up with solution to the problem based on least amount of effort on their part along with maximizing profit, such as replacing with new rather than repair.

Companies and individuals must make a profit to stay in business or they won't be around next year when you need them again. Here at Light Plane Maintenance we do encourage owner participation and I personally enjoy working with owners on maintenance of their aircraft. However, it can get annoying when I get resistance toward my findings that something is unsafe and needs to be corrected.

I also get annoyed when inexperienced people go off on their own with no previous background on aviation procedures and end up damaging or destroying a part or component of an airplane, because they either don't know what they are doing or don't have the proper tools for the job, and we don't have to discuss the illegal aspects here of such actions. Often all three components are present at once.

It often is simply because the owner didn't take the time to get information on how to do something correctly. I once had an owner break a seat rail on a Cessna 150 during the seat removal process preparing for an annual inspection. There were several factors that came into play during this operation in that I mistakenly assumed that the owner had taken the seats out of his plane before but he had not.

I also discovered that the carpeting material was thicker than the original and did not meet the requirements for fire safety for an aircraft. The thicker material obstructed the seat movement and clearance and the owner forced the seat rearwards and upward enough to break off the aft section of the seat rail on the pilots' side, which had to be replaced.

I might add that the seats must be removed not only as an annual inspection requirement but AD note 11 10 09 (formerly AD 87 20 03) requires in the text of the AD that the seats must be removed from the aircraft for inspection. I must admit that I was partially to blame in not taking the time to at least ask if the owner had taken the seats out before or if he was familiar with the procedure (that's a mistake I never made again).

This is one of the many reasons why commercial shops don't often get into owner assisted annuals; it takes more time to do the annual and parts get damaged requiring extra time to repair or at least correct the problem created by the owner. Some shops claim they charge significantly more if an owner wants to participate and ask endless questions, and this is irrespective of owner caused damage.

It's OK not to know how to do something and it's OK for an owner to decline to do certain operations. It's smart to know when to say no and let the professional do it or show you how to do it. Many times there are tools locally made that you can't buy and tricks of the trade that are not well known outside of professional circles that some mechanics are unwilling to share with others not in the pro circle side of things.

That's OK and I may not always share everything that I have learned during one annual but over the course of a several annuals on the same plane and owner I do share most of my knowledge, which some appreciate and others don't, for reasons I cannot understand.

Inspection findings recently changed for me as a result of geographic base changes from the Eastern US to the Western US. I inspect a new group of planes that have different issues because of where they are based and how they are operated.

The frequency of use (planes sitting idle for weeks) is of course an issue that doesn't change much with the geography but more so with the economy and high fuel prices. What I have been seeing is cracked wing tips, stabilator tips, and plastic exterior parts of planes. Unless there are specific FAA approved repair procedures or allowable limits of cracks and damage to these parts the part has to be replaced with a serviceable FAA approved part.

I spotted a vertical fin cap on a Cessna that was in extremely bad condition and ready to fail maybe on the very next flight. When I pointed out the problem the owner of the plane countered my unsafe condition statement with the statement that this part has been cracked for several years and that the last two inspectors didn't complain about it and signed off the plane as airworthy. I understand that maybe the part wasn't as badly cracked last year, or maybe the previous inspector didn't notice it, or thought that it was OK but now it appears to me that it's time to replace the part.

If this cap breaks off, and it will at some point, not only will it result in damage to the plane since the flashing beacon is attached to the cap by wires, it may also interfere with the operation of the rudder, which was the reason I determined that this is an unsafe condition.

Airworthiness Directives can be a big deal as no matter how simple or complicated the corrective action there is an unsafe condition associated with the AD that must be addressed. If an AD does not apply to your aircraft then have a statement entered in the maintenance records as to why it doesn't apply (such as different serial number series) but don't ignore it because it doesn't apply. This can come back to haunt you.

What I have seen on more than one recent annual is that AD notes that were signed off years ago as complied with and the corrective action listed correctly are mysteriously no longer in compliance. How could this be? Sometimes repairs are made to an airplane without consideration of AD notes that may be impacted by a repair.

Also, people who are unaware of an AD may innocently replace a fuel cap that did comply with an AD note with a fuel cap that isn't in compliance. Take a look at Cessna AD 79 10 14 and revision 1 and Cessna service letter 77-6 for details including part numbers, placards required and what fuel caps are necessary.

Piper aircraft are not exempt from AD notes that were complied with but also fall out of compliance. There is a provision for 95 26 13 oil cooler hoses that if the oil cooler hoses are replaced with a TSO C53A type D hose assembly the repetitive inspection requirement is no longer required.

If these hoses are replaced by hoses that do not meet the requirements of TSO C53A type D hose, then the repetitive inspection process once again if effect. While attending an FAA sponsored IA renewal program one statement by the speaker that really stands out is there are far more violations issued to mechanics because of AD notes being missed or not complied with as part of scheduled inspections than there are any other reason for a violation.

Airworthiness Directives are issued because they identify an unsafe condition so it would seem to be improper to sign off an annual with an open AD note. All AD notes must be addressed (even if they don't apply) stating the reason why they don't or how the AD was complied with or if not complied with (such as awaiting parts) a statement when the AD note is due. It is the pilots' responsibility to not operate an aircraft with an AD note that is past due or be subject of a violation and would have invalid insurance should there be an accident.

Cleaning an aircraft inside and out is a requirement prior to inspection as stated in FAR 43 appendix D. I see many aircraft that are not so they must be cleaned prior to an inspection. This is often overlooked by owners and inspectors but is very important. You can do it yourself for free; just coordinate with the IA.

Dirty aircraft accelerate wear and corrosion and prevent a good inspection from being accomplished. While people may argue that a leak, crack or other deficiency may be discovered or traced because the aircraft is dirty, it is a fact that dirt, grime and gunk from hydraulic or oil leaks often mask serious problems such as cracked crankcases, leaking hydraulic hoses or fluid fittings that are damaged and not airworthy.

Corrosion of metal airplanes is a continuing problem and quite costly to correct or repair but relatively easy to prevent by maintaining an aircraft in a clean condition. Aircraft that are not flown frequently as it the case now with most general aviation aircraft seem to have more corrosion than in the recent past. A factor to consider is that moisture mixed with any type of dirt, oil, grease etc can accelerate the corrosion process.

Almost every aircraft I prepare to inspect has a dirty belly with corrosion either starting or already progressing into the structure of the aircraft. I have seen some aircraft with lower fuselage corrosion so bad that I could poke my finger through the skin. Consider these factors when dealing with cleaning an aircraft and issues of corrosion prevention before it gets damaged to this point.

Interiors of fuselages have multiple drains or weep holes that must not be obstructed with dirt or debris. During the annual inspection if any of these lower fuselage areas have any debris lying around it must be removed. This includes rivet heads, metal shavings, dirt, rodent droppings, and straw from birds' nests, etc.

The best way to remove this unwanted material is to vacuum it out during the annual when you have ease of access to these areas. Water will not remove the debris or dirt but only serve to force it into areas that you may not see but will trap the water and set up the perfect environment for corrosion.

An additional danger from plugged drain holes is that water trapped in the lower aft fuselage significantly alters weight and balance figures and can make the aircraft uncontrollable in certain flight regimes.

Cleaning an aircraft is important but so is the type of material used for cleaning. Grocery store cleaners such as Simple Green (not the aviation version) are not intended for use on aluminum and cause corrosion. This cleaner has specifically been traced to at least one aircraft accident that was the result of hydrogen embrittlement in a critical structural component. Use only approved materials and procedures intended for aircraft.

Inspection Authorization authenticity came up for discussion during the IA renewal meeting where an IA may not be authorized to sign off an annual inspection and those annuals that were signed off would not be valid.

The once standard annual renewal process in March of every year was changed to a two-year renewal process several years ago. While the change was somewhat confusing at first it's the rule now that the activities that are recognized as meeting the currency requirements for the authorization are still in effect. It's something like the pilot currency requirement for three take offs and landings in 90 days.

Pilots understand this rule and inspectors should understand the currency requirements for them to exercise their authorization. Federal Air Regulation 65.93 is very specific about what is required to maintain an IA certification and addresses the two-year renewal program. While he or she may hold the authorization card for you to see it is very possible that since the IA did not meet the activity requirements for year one of the two year renewal period that annuals signed off after March 31 of the first year are not valid.

An aircraft owner could get a letter from the FAA stating that your annual inspection could be invalid. Wouldn't this be a mess to get involved with? Unfortunately this has happened more than a few times with this relatively new two-year renewal program for IAs.

Wrapping up the discussion as an aircraft owner you need to stay on top of not only the maintenance of your aircraft but also the paperwork and ensure that you keep your aircraft up to date. Don't ignore letters from the FAA, manufacturers' service bulletins that show up in your mailbox, and don't wait until the annual is due to open up AD notes or revisions issued for your aircraft, engine or prop.

Ensure that your current address is on file with the FAA and also with the manufacturer of the aircraft as well. Finally, work with your mechanic to show you or explain how to perform a task on your aircraft that may be allowed as preventive maintenance.

Airplane parts are expensive so mistakes made can quickly become costly or dangerous. We here at Light Plane Maintenance strive to make aircraft ownership safe and enjoyable while protecting your investment. And all IA work I do is as a freelancer, and has no affiliation with LPM Magazine.

Mike Berry holds A&P ratings with Inspection Authorization.

This article originally appeared in the June 2013 issue of Light Plane Maintenance.

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