Welcome to the final part of a four-part series that explains what constitutes aircraft maintenance from an FAA perspective and what are the differences between the elements that make up aircraft maintenance?
In this article, we look at what is not a maintenance activity.
ACTIVITIES WHICH ARE NOT MAINTENANCE
It is mistakenly believed that if something has the potential to cause harm to the aircraft or its operation, the activity should be covered as a maintenance activity. That perception probably has ties to the language that is used in the definition of a “major repair” in § 1.1: “Major repair means a repair: (1) That, if improperly done, might appreciably affect weight, balance, structural strength, performance, powerplant operation, flight characteristics, or other qualities affecting airworthiness…” This has led people to improperly classify some activities that could affect the airworthiness of the aircraft, if done improperly, as maintenance.
These activities include:
Excluded from the definition of maintenance, preventive maintenance applies to a special category of items that have been identified and defined in the regulations as not rising to the level of maintenance. Preventive maintenance is defined in §1.1 as “…simple or minor preservation operations and the replacement of small standard parts not involving complex assembly operations.”
Part 43 appendix A, paragraph (c) contains a limited specific list of items the FAA has defined as preventive maintenance. Items of preventive maintenance can include:
- Replenishing aircraft oxygen systems through a single servicing port (except when fittings, other than a cap, need to be disconnected and reconnected);
- Replenishing medical oxygen systems that can be removed and filled without tools, or aircraft mounted systems that can be serviced without tools (except when fittings, other than a servicing port cap, need to be disconnected and reconnected);
- Adding air and/or oil to landing gear shock struts;
- Replenishing hydraulic fluid in the hydraulic reservoir; and
- Replacing or servicing batteries.
Paragraph 4(b)(1) of AC 43-12, Preventative Maintenance, also cautions that “because of differences in aircraft, a function may be preventive maintenance on one aircraft and not on another.” For example, the FAA may agree that the pilot of a small General Aviation (GA) airplane may change and repair its landing gear tire as preventive maintenance but would not consider the changing and repair of a landing gear tire on a transport category airplane to be preventive maintenance that a pilot could do. This is clarified by the definition of preventive maintenance in §1.1 as being limited to “simple or minor preservation operations” and it “not involving complex assembly operations”. Even though the task might be listed in part 43 appendix A, paragraph (c), it does not mean that every repetition of that task would be considered preventive maintenance.
Routine cleaning such as the removal of dirt and debris from the interior and exterior of the aircraft is not considered as maintenance or preventive maintenance. However, note that the manufacturer’s procedure for washing an aircraft may include tasks that might be classified as maintenance. These tasks might be required either before or after cleaning or as the result of other maintenance tasks. Examples include pulling and tagging certain circuit breakers, the installation of protective devices to protect sensitive areas (other than simple slide-on covers), or replacement of defective or damaged gaskets or sealants found during the washing procedure.
A visual check is an observation to determine that an item is fulfilling its intended purpose and that does not require quantitative tolerances. Visual checks do not include inspections that are performed as part of a scheduled maintenance activity, called for in an inspection program, or performed as the result of an associated maintenance activity (such as a part replacement, repair, or overhaul of a product or article). Those types of inspections are maintenance. However, a simple visual check, even if performed by a certificated maintenance person, is not maintenance. For example, a pre-flight inspection performed by a pilot is a visual check but is not a maintenance activity.
Some forms of servicing are preventive maintenance, which have regulatory requirements. For example, a record entry is required per §43.9 for items of preventive maintenance performed. Generally, basic servicing tasks, such as fuelling and adding oil, are neither maintenance nor preventive maintenance. However, when adding oil requires a precise sequence of steps or partial disassembly to gain access, then that would be considered a maintenance activity. Adding oil to an oleo strut, for example, would be a maintenance activity.
Alterations are not maintenance. They have their own set of rules and regulations that must be followed, but altering a product or article is not a maintenance activity by definition. However, many functions that need to be carried out with performing an alteration are maintenance, but the alteration itself is not.
Rebuilding a product or article is strictly an activity performed by the manufacturer of the part. The term “rebuild” is not included in the definition of maintenance. Section 43.3(a) states, in part, that “Except as provided in this section and §43.17, no person may maintain, rebuild, alter, or perform preventive maintenance on an aircraft, airframe, aircraft engine, propeller, appliance, or component part to which this part applies.”
Again, maintaining, rebuilding, altering, and preventive maintenance are all separate and unique activities. Section 43.3(j) states, in part, that: “A manufacturer may (1) Rebuild or alter any aircraft, aircraft engine, propeller, or appliance manufactured by him under a type or production certificate; (2) Rebuild or alter any appliance or part of aircraft, aircraft engines, propellers, or appliances manufactured by him under a Technical Standard Order Authorization, an FAA‑Parts Manufacturer Approval, or Product and Process Specification issued by the Administrator.” In this case, the manufacturer is the only entity identified as being allowed to rebuild a product or article.
Further description of what rebuilding involves is published in §43.2(b) as: “No person may describe in any required maintenance entry or form an aircraft, airframe, aircraft engine, propeller, appliance, or component part as being rebuilt unless it has been disassembled, cleaned, inspected, repaired as necessary, reassembled, and tested to the same tolerances and limits as a new item, using either new parts or used parts that either conform to new part tolerances and limits or to approved oversized or undersized dimensions.”
In most cases, changing or loading software onto an aircraft component or system is a maintenance activity. One specific exemption is provided in §43.3(k) for pilot-managed aeronautical databases. Additionally, loading of In-Flight Entertainment (IFE) system content software, defined in RTCA DO-178 as level E, is also not maintenance and is therefore excepted from §43.9. IFE “content only” software is described as a movie, music, and game programs with no effect on system operation.