top of page

The aircraft inspection process

Having realistic expectations for the annual inspection process on your aircraft should not have to be a big deal. The biggest concern should be the connection that you establish with a maintenance provider whom you will trust with all the details pertaining to your aircraft. While there is no way that your maintenance provider will be able to provide you with a complete estimate right up front, he should be able to make the inspection process clear as it will be dependent on the nature of the defects yet to be found on the aircraft.

Once that maintainer gets to know your aircraft through repeat visits and consultation, the inspection process will gradually become a little more predictable. At the very least, you should be provided with a good estimate based on the inspection phase itself and any other scheduled work that is due at that time. This inspection phase is sometimes determined by a flat rate based on the size or complexity of the aircraft and takes into account more complex engine and propeller configurations, retractable landing gear or pressurization systems.

The quotation process should cover a brief overview of the job, the estimated down time, identification of who will be doing the work and any optional extras to be contemplated. Addressing the unknown cost of additional work cannot be determined until the inspection phase is complete. The second phase of the quotation process then lets the owner know whether the inspection itself uncovered any defects or concerns. Remember that the inspection itself is not necessarily the complete job. The inspection activity is meant to find problems (or potential issues) with the aircraft. The inspection package will include each of the additional findings and only an owner authorized response will determine how each finding is to be addressed.

Each item would first be evaluated by the AME to determine how the finding affects the overall airworthiness of the aircraft. This is where communication with the customer becomes more interactive because decisions can still be made based upon preferences and/or certain costs. Items affecting airworthiness will be noted as needing done regardless of cost or projected down time. These issues directly affect the Certificate of Airworthiness which remains temporarily suspended as long as the item is not addressed. This is the chance you take with aircraft ownership. You must know and accept this as an ownership reality. Aircraft are man-made structures that are susceptible to normal wear and tear just like your car, boat or lawnmower. Other items may not affect airworthiness and may be deferred to a later date in accordance with any preferences or stated regulatory limitations as applicable. These optional items give the owner the opportunity to defer the repair (and the associated cost) until a later date. So there is some flexibility.

The AME will always provide experienced counsel regarding items deemed not to be necessary to the normal role of the aircraft. The decision whether to proceed with any maintenance work always rests with the owner as having custody and control of the aircraft and thereby accepting the responsibility for its state of airworthiness. The decision to not act upon a required airworthiness item puts the AME on the spot as he then has a professional and ethical obligation to make that decision known directly in the log book where the completed work is to be certified. Owners who choose this path must accept the responsibility for their decision and remove the burden from the AME who is responsible only for his part in regulatory compliance through his work entry and signature. This can easily become a legal issue where the AME should never have to be pressured into making a bad decision based on convenience or economics over safety.

There seems to be less regulatory oversight of private aircraft these days and the temptation to maybe let certain things slide lurks in the background. Keeping up with the airworthiness requirements should never be taken lightly even though certain tasks may seem inconsequential. Some aircraft owners may not realize that when airworthiness items are passed over yielding to the real motivator of saving money, the airworthiness of the aircraft becomes compromised. The aircraft technical logs still tell a story which may influence your insurance coverage should something happen. An unfortunate incident or accident could easily turn into a higher price to pay for not doing the right thing in the first place. The selection of the proper shop or AME becomes apparent here as these maintenance professionals should be considered the experts on the various maintenance requirements. If you do not trust them or feel that you have to keep an eye on them as you bargain for a cheaper rate then you may need to reconsider your motives as a willing participant in this industry. The stakes are too high for everyone involved.

The ongoing communication between the aircraft owner and the maintenance provider should establish a main point of contact at both ends. Relaying messages or opinions through other people is a recipe for confusion and mistrust. Modern technology permits us to exchange emails when people are busy at work or not able to take calls concerning the progress of the inspection. Digital photographs may also be sent to explain a technical condition that could not be explained clearly otherwise. The inferred result of the ongoing communication is to ensure that the customer gets what they expect based on the ongoing feedback from the AME. Imagine getting the necessary work done to your aircraft, being kept in the loop throughout the process and then receiving an invoice that does not knock you over in surprise! It is possible with a mature and responsible approach to surviving routine maintenance expenses.

The engine of the aircraft is usually the most costly item and therefore demands the most attention and concern over its operation and servicing requirements. There are also as many differing opinions and experiences with engine care and feeding as there are engines. One of the more common methods used to determine engine health is the differential compression test. This is a test using calibrated gauges to determine the amount of air pressure captured in the cylinder head while on the compression stroke. The results of this test are related to the engine’s overall power output. Many owners who have an idea of its significance often want to know the results. The compression results however, are also dependant upon the temperature of the engine when the test is being performed, the condition of the valves at that time, the random orientation of rings and whether the engine has been recently active. Sometimes the test results require a subsequent test to narrow down the source of any observations noted on the first test. Internal corrosion is another issue with piston engines. The longer that the engine sits inactive, the greater the chances of internal corrosion developing due to condensation and lack of oil protection on exposed parts. Preventative measures include engine preservation, climate controlled storage and frequent use. This also brings up the debate of what type of oil is best suited to your engine. There are more opinions on this topic than choices of oil. Talk to your AME and make an informed decision based upon seasonal utilization and your particular engine requirements. The rest is mainly based on preference. Regular oil changes should include inspection of oil screens and the spin-on filter element for clues to internal wear activity. Spectrographic oil analysis is another more detailed method of tracking internal wear metals and can be an effective maintenance tool if done consistently. Tracking oil analysis reports aids the owner in determining engine wear patterns while still in the early stages as compared to waiting to see larger contaminants in the filter once the wear (and potential damage) has progressed even further. Oil analysis kits are very affordable, easily tracked and may be well worth the investment in the long run.

One of the primary concerns when considering the airframe inspection is seeing evidence of internal (and sometimes external) corrosion. Once this condition has become evident it must be treated sooner than later. Depending on the extent of corrosion, the affected area may only require a treatment of ACF 50 or similar corrosion inhibiting product. More serious cases require repair or replacement of skins prior to the cleaning and treating process. Some cases where corrosion is detected under the paint may require much more extensive work to ensure that corroded elements are completely removed. Guidelines for this and all other areas of inspection are derived from the maintenance manuals and associated industry standards and practices. This leads us to an area where the AME must be on his game. Any work that the AME is tasked with doing must be referenced to a maintenance standard. This ensures that the work is being performed in a manner that has either been approved or accepted by the industry and ultimately the regulating authority.

Regardless of the type of shop you have chosen to do the work on your aircraft, the AME must be able to source the relevant standards pertaining to the nature of work being done. As an owner you may not have any idea what those standards are but the very least of these should be the manufacturer’s maintenance manual for the aircraft. These manuals and all associated Directives, Bulletins and reference materials are considered the Instructions for Continued Airworthiness (ICA’s).They will include the necessary information needed by the maintainer to perform the work that will sustain the airworthiness of the aircraft being maintained. An Approved Maintenance Organization (AMO) is deemed by Transport Canada as having these resources in place according to a policy manual stating how all aspects of maintenance are performed within their specific environment. This recognition of controlled systems permits the AMO to work on private or commercially registered aircraft as identified on their scope of approval. The scope identifies the types of aircraft that the AMO are equipped for and trained to maintain. Smaller unapproved shops are not required to have as elaborate systems in place but nevertheless may be equipped and trained to do the job as good as any AMO. The key to a good shop is doing your homework and seeking out what type of reputation these shops have whether they are approved or not.

The last word on the maintenance provider’s responsibility in the annual inspection process rests with CAR 571 Aircraft Maintenance Requirements. CAR 571.02 clearly states in part that “a person who performs maintenance on an aeronautical product shall use the most recent methods, techniques, practices, parts, materials, tools, equipment and test apparatuses that are (a) specified for the aeronautical product in the most recent maintenance manual or Instructions for Continued Airworthiness developed by the manufacturer of that aeronautical product”. Parts (b) and (c) go on to include equivalent methods and recognized industry practices. The AME has a lot to live up to in terms of regulatory compliance and it usually ends up being his duty to also inform the owner of how all these requirements affect the airworthiness of the aircraft. The regulatory assignment of clearly dividing the responsibility between the owner and the maintainer ensures that the owner requests only what he/she wants done (over and above the airworthiness items) and that the AME performs that work using only approved procedures.

30 views0 comments

Recent Posts

See All


Join our mailing list

Thanks for subscribing!

bottom of page