Maintenance Record Entries: Required Content and Mechanic Signature Standards

Every time a certificated mechanic performs an inspection, repair, alteration, or overhaul on an aircraft, they must create a maintenance record entry that meets strict FAA standards. These entries are not bureaucratic formalities—they are the legal evidence that airworthiness work was performed correctly, by qualified personnel, and in accordance with approved data. A missing signature, an incomplete description, or a wrong certificate number can render an aircraft technically unairworthy and expose the mechanic to certificate action under 14 CFR Part 43 and Part 65.

For AMT General knowledge-test candidates, maintenance record entries are a high-yield topic. The FAA tests not only what must appear in an entry but also who can make specific entries, what words are legally significant, and what happens when an entry is deficient. This article covers all of it thoroughly so you understand the rules at a level that will serve you both on the written exam and throughout your career on the flight line.

Legal Basis: Where the Requirements Come From

The primary regulatory authority for maintenance record entries is 14 CFR Part 43, Appendix B. This appendix lists the minimum content required in maintenance records for both major and minor repairs and alterations, as well as for required inspections such as annual and 100-hour inspections. The companion regulation, 14 CFR §43.9, governs content requirements for maintenance, preventive maintenance, rebuilding, and alteration records. Section §43.11 addresses the specific content required for inspection entries.

Additionally, 14 CFR §65.80 speaks to the privileges and limitations of certificated mechanics, and §65.95 covers inspection authorization (IA) holders. Together, these sections define who may make which type of entry and what authority each signature represents.

Required Content Under §43.9: General Maintenance Entries

For any maintenance, preventive maintenance, rebuilding, or alteration performed on an aircraft, engine, propeller, or appliance, the maintenance record entry must contain the following minimum elements:

Description of the work performed: The entry must describe the work in enough detail that a future reader—another mechanic, an FAA inspector, or an NTSB investigator—can understand exactly what was done. Vague terms like "repaired engine" are insufficient. A proper entry might read: "Replaced No. 3 cylinder on Lycoming O-360-A1A per manufacturer's overhaul manual, Chapter 5. Cylinder installed with new rings, gaskets, and studs. Compression checked: 72/80." The FAA looks for who, what, where, and how.
Date the work was completed: The date must reflect when the work was actually completed and the aircraft returned to service, not when the paperwork was filled out later.
Name of the person performing the work (printed or typed): This identifies accountability. If someone other than the approving mechanic performed the physical work under supervision, clarity in the entry can matter during investigations.
Signature: The certificated mechanic must sign the entry in their own hand. A rubber stamp signature is not acceptable as a substitute for an original signature.
Certificate number: The mechanic must include their FAA airman certificate number. This is not optional. The certificate number allows the FAA to verify that the person who signed the entry actually held the appropriate rating at the time.
Certificate type held: The entry must state the type of certificate—for example, "Mechanic Certificate" or "Repairman Certificate." If the mechanic holds both Airframe and Powerplant ratings, it is common practice to indicate which rating authorizes the specific work performed, though regulations do not require specifying the rating in §43.9 entries (the rating becomes critical, however, for the approval for return to service).

Inspection Entries Under §43.11

When a certificated mechanic with an IA, or an authorized representative of a certificated repair station, performs an annual inspection or a 100-hour inspection, the entry has additional requirements beyond those of §43.9. Under §43.11, the record must include:

The type of inspection performed (e.g., annual inspection or 100-hour inspection).
A statement that the aircraft was inspected in accordance with the applicable regulations.
Whether the aircraft is airworthy or unairworthy, and if unairworthy, a list of the discrepancies found. This is the legally critical language discussed in more detail below.
The date of inspection.
The total time in service of the airframe.
The signature, certificate number, and type of certificate held by the person approving or disapproving the aircraft for return to service.

It is important to understand that a 100-hour inspection may be approved for return to service by a certificated mechanic holding both Airframe and Powerplant ratings, but an annual inspection may only be approved for return to service by a mechanic holding an Inspection Authorization (IA). The signature on an annual inspection entry without an IA number is legally meaningless as an approval.

The Airworthy / Unairworthy Language

One of the most commonly tested concepts on the AMT General exam is the correct language for inspection sign-offs. When an aircraft passes inspection, the approving mechanic must state that the aircraft has been inspected and found to be in airworthy condition. When an aircraft fails inspection due to discrepancies, the entry must state that the aircraft was inspected and found to be unairworthy, with each discrepancy listed.

A critical point: the owner or operator is responsible for correcting discrepancies before the aircraft is returned to service. The mechanic who performed the inspection is not required to repair the discrepancies in order to close the inspection record—they are required to document them. However, until either the discrepancies are corrected and a new airworthy entry is made, or a ferry permit is obtained under 14 CFR §21.197, the aircraft may not be operated in normal flight.

Who May Make Which Entry

Understanding signature authority is fundamental to compliance:

A mechanic with an Airframe (A) rating may approve airframe work for return to service and sign the corresponding entry.
A mechanic with a Powerplant (P) rating may approve powerplant work for return to service and sign that entry.
A mechanic holding both A&P ratings may perform and approve all work within those privileges.
Only an IA holder may approve an aircraft for return to service following an annual inspection. A major repair or major alteration may be approved for return to service by an appropriately rated A&P mechanic, repair station, or manufacturer authorized to perform that work (documented on FAA Form 337); an IA is not required solely for this purpose.
A certificated repair station may approve work within its ratings through its authorized inspectors.
The aircraft manufacturer may approve for return to service aircraft it has manufactured and for which it holds a Production Approval.

FAA Form 337 and Major Repairs/Alterations

When a major repair or major alteration is performed, the work must be documented on FAA Form 337 (Major Repair and Alteration) in addition to the aircraft's maintenance records. The Form 337 must describe the repair or alteration, reference the approved data used, and be signed by an IA or an authorized representative of the FAA. One copy is retained with the aircraft records; the other is submitted to the FAA Aircraft Registration Branch within 48 hours after the aircraft is approved for return to service. Failing to file Form 337 is a regulatory violation even if the underlying work was performed correctly.

Key Numbers and Rules

§43.9 — governs content of general maintenance record entries (description, date, name, signature, certificate number, certificate type).
§43.11 — governs content of inspection entries; adds total time in service and airworthy/unairworthy language.
Annual inspection sign-off — requires an IA; an A&P alone cannot approve for return to service.
100-hour inspection sign-off — may be approved by an A&P mechanic (no IA required).
Form 337 submission — must reach FAA within 48 hours of return to service for major repairs/alterations.
Total time in service — must appear in annual and 100-hour inspection entries; not required in routine maintenance entries under §43.9.
Rubber stamp signatures — not acceptable; original handwritten signature required.

Common Test Traps

Confusing §43.9 and §43.11 requirements: Section 43.9 covers maintenance entries; §43.11 covers inspection entries. The total time in service of the airframe is required in §43.11 inspection entries but is NOT a required element of routine §43.9 maintenance entries. Many candidates mix these up.
Assuming an A&P can approve an annual: Only an IA holder may return an aircraft to service following an annual inspection. An A&P without an IA may perform the physical inspection work under an IA's supervision, but the approving signature must belong to the IA.
Forgetting the certificate number: A signature alone is not sufficient. The FAA requires the certificate number in the entry. Leaving it out is a regulatory violation regardless of how thorough the work description is.
Vague work descriptions: Entries that say "inspected and repaired" without specifics do not meet the standard. The FAA expects enough detail to reconstruct what was done from the written record alone.
Unairworthy aircraft and the owner's responsibility: Students sometimes think the inspecting mechanic must fix discrepancies to close the inspection. The regulation requires the mechanic to document discrepancies—the owner or operator is responsible for correcting them before flight.