As a maintainer, I used to be confused at times, about where to record different types of maintenance I performed on U.S. aircraft. I am sure in the past I made some mistakes in my record keeping. The FAA does provide guidance in how and where to record maintenance and inspection for Airframe and Powerplant (A&P) mechanics as well as others.
The guidance for maintenance and inspections performed is found in two FAA regulations part 43 and part 91. Keep in mind that maintenance and inspections is recorded different and require different ratings and authorizations to perform some tasks.
Advisory Circular (AC) 43.9C describes methods, procedures and practices that have been determined to be acceptable means of showing compliance with the general aviation maintenance record making and record keeping requirements of Title 14 of the Code of Federal Regulations ( 14 CFR) parts 43 and 91. This material in ACs is not mandatory, nor is it regulatory and acknowledges that the Federal Aviation Administration (FAA) will consider other methods that may be presented. It is issued for guidance purposes and outlines several methods of compliance with the regulations.
A quick review of what a mechanic can perform and sign off in accordance with part 65 mechanic limitations. An A&P can perform maintenance in accordance with part 65 Subpart D, §65.81 General privileges and limitations, §65.83 Recent experience requirements, §65.85 Airframe rating; additional privileges, §65.87 Powerplant rating; additional privileges, and §65.95 Inspection authorization: Privileges and limitations. I will not go into detail on these as I will assume the person performing maintenance or preventive maintenance holds the proper ratings.
First, let’s define maintenance in accordance with CFR 1.1. Maintenance means inspection, overhaul, repair, preservation, and the replacement of parts, but excludes preventive maintenance.
Second, Preventive maintenance means simple or minor preservation operations and the replacement of small standard parts not involving complex assembly operations. Preventive maintenance is what pilots can do in accordance with part 43 Appendix A Preventive Maintenance, however it should be recorded in the same manner as part 43.9(a) describes for mechanics. Qualified persons, who perform the maintenance, preventive maintenance and alterations, shall make a record entry of this accomplishment, thus maintaining the validity of the certificate of airworthiness. Adequate aircraft records provide tangible evidence that the aircraft complies with the appropriate Airworthiness Certificate.
Part 91, Section 91.405 requires each owner or operator to ensure that maintenance personnel make appropriate entries in the maintenance records to indicate that the aircraft has been approved for return to service. In other words, the owners are responsible that maintainers make the correct record entries in the proper place. Section 91.7 also makes the owner responsible for the airworthiness of the aircraft NOT the mechanic. Aircraft records is the only way of showing compliance with maintenance and to determine the airworthiness of the aircraft for the work performed.
There are two FAR/CFRs that maintenance people should understand part 43.9 and part 91.417 these two rules read similar, but are different.
§43.9 Content, form, and disposition of maintenance, preventive maintenance, rebuilding, and alteration records (except inspections performed in accordance with part 91, part 125, §135.411(a)(1), and §135.419 of this chapter).
(a) Maintenance record entries. Except as provided in paragraphs (b) and (c) of this section, each person who maintains, performs preventive maintenance, rebuilds, or alters an aircraft, airframe, aircraft engine, propeller, appliance, or component part shall make an entry in the maintenance record of that equipment containing the following information:
(1) A description (or reference to data acceptable to the Administrator) of work performed.
(2) The date of completion of the work performed.
(3) The name of the person performing the work if other than the person specified in paragraph (a)(4) of this section.
(4) If the work performed on the aircraft, airframe, aircraft engine, propeller, appliance, or component part has been performed satisfactorily, the signature, certificate number, and kind of certificate held by the person approving the work. The signature constitutes the approval for return to service only for the work performed.
§91.417 Maintenance records.
(a) Except for work performed in accordance with §§91.411 and 91.413, each registered owner or operator shall keep the following records for the periods specified in paragraph (b) of this section:
(1) Records of the maintenance, preventive maintenance, and alteration and records of the 100-hour, annual, progressive, and other required or approved inspections, as appropriate, for each aircraft (including the airframe) and each engine, propeller, rotor, and appliance of an aircraft. The records must include—
(i) A description (or reference to data acceptable to the Administrator) of the work performed; and
(ii) The date of completion of the work performed; and
(iii) The signature, and certificate number of the person approving the aircraft for return to service.
(2) Records containing the following information:
(i) The total time in service of the airframe, each engine, each propeller, and each rotor.
(ii) The current status of life-limited parts of each airframe, engine, propeller, rotor, and appliance.
(iii) The time since last overhaul of all items installed on the aircraft which are required to be overhauled on a specified time basis.
(iv) The current inspection status of the aircraft, including the time since the last inspection required by the inspection program under which the aircraft and its appliances are maintained.
(v) The current status of applicable airworthiness directives (AD) and safety directives including, for each, the method of compliance, the AD or safety directive number and revision date. If the AD or safety directive involves recurring action, the time and date when the next action is required.
(vi) Copies of the forms prescribed by §43.9(d) of this chapter for each major alteration to the airframe and currently installed engines, rotors, propellers, and appliances.
To sum up the two rules part 43 and part 91 requires A&P mechanics to record maintenance they perform in the aircraft records. Section 91.417(a)(l)(i). Requires the maintenance record entry to include “a description of the work performed.” The description should be in sufficient detail to permit a person unfamiliar with the work to understand what was done, and the methods and procedures used in doing it. When the work is extensive, this results in a voluminous record. To provide for this contingency, the rule permits reference to technical data acceptable to the Administrator in lieu of making the detailed entry. Manufacturer’s manuals, service letters, bulletins, work orders, FAA AC’s, and others, which accurately describe what was done, or how it was done, may be referenced. Except for the documents mentioned, which are in common usage, referenced documents are to be made a part of the maintenance records and retained in accordance with section 9 1.417(b).
Aircraft records can be airframe, engine, propeller, avionic logbooks or binders. Part 91 was changed many years ago that changed for the term logbooks to aircraft records. What this means is aircraft records can be any document that meets the requirements of Section 43.9 such as a repair station work order or individual documents the meet the requirements of Sections 43.9.
Questions continue regarding multiple entries for 100-hour/annual inspections. Neither part 43 nor part 91 requires separate records to be kept. Section 43.11, however, requires persons approving or disapproving equipment for return to service, after any required inspection, to make an entry in the record of that equipment. Therefore, when an owner maintains a single record, the entry of the 100-hour or annual inspection is made in that record. If the owner maintains separate records for the airframe, powerplants, and propellers, the entry for the 100-hour inspection is entered in each, while the annual inspection is only required to be entered into the airframe record.
There is a growing trend toward computerized maintenance records. Many of these systems are offered to owners/operators on a commercial basis. While these are excellent scheduling systems, alone they normally do not meet the requirements of sections 43.9 or 91.417. The owner/operator who uses such a system is required to ensure that it provides the information required by section 91.417, including
Many Aircraft Owners and Operators have expressed a concern about whether or not there is a requirement for maintenance record entries to be legible.
If we review Title 14 Code of Federal Regulations (CFR) Part 43, Section 43.9, we will see that the regulations does not have specific guidance concerning legibility requirements. However, if we look at Amendment 43-23, 47 Federal Register (FR) 41085, Sept. 16, 1982, we will find the following statement from the FAA: "Since legibility is a practical necessity and entries which are not legible do not satisfy the purpose of Section 43.9."
Therefore, it seems that when we look at maintenance records, the entries, including signatures and certificate numbers, should be legible.
What is important to understand is the signature makes the aircraft record a legal document. Section 43.9 required the mechanic NAME and SIGNATURE; the signature constitutes the approval for return to service only for the work performed.