Definition
An FAA-published advisory circular that provides accepted methods, techniques, and practices for the inspection and repair of non-pressurized civil aircraft. It is used by mechanics and repair stations as a reference when no manufacturer-approved data is available, and includes guidance relevant to weight and balance, such as recording equipment changes and maintaining the aircraft's empty weight and center of gravity records.
Plain English
An FAA reference book that tells mechanics how to inspect and repair small aircraft when the manufacturer hasn't given specific instructions. It also covers how to keep the aircraft's weight records up to date.
Context Anchor
Seen in maintenance, aircraft records, and weight-and-balance discussions when repairs or equipment changes may affect the aircraft’s empty weight or balance data.
Derivation
"Advisory Circular" simply means a non-regulatory FAA publication that advises how to comply with the rules. The number 43.13-1 ties it to Title 14 CFR Part 43, which covers maintenance.
Why Pilots Care
Using the methods in this circular keeps the aircraft legally airworthy and prevents dangerous loading conditions that could affect flight safety.
Intuition Check
Do not read “advisory” as “casual advice.” An Advisory Circular is not usually a regulation by itself, but it is official FAA guidance and may be used as an accepted standard when it applies.
Example Sentence 1
After installing the new avionics, the mechanic followed AC 43.13-1 procedures and updated the aircraft's weight and balance records.
Example Sentence 2
The pilot verified that all weight changes had been documented according to AC 43.13-1 before the next flight.