Definition
An Advisory Circular (AC) is a non-regulatory document issued by the Federal Aviation Administration to provide guidance, recommended practices, methods, or information about a specific subject area in aviation. ACs explain how to comply with regulations, share best practices, and clarify FAA policy, but they do not themselves carry the force of law unless a regulation specifically incorporates them.
Plain English
An official FAA document that explains and advises rather than commands. It tells pilots, instructors, and operators how the FAA recommends doing something, or how to meet a rule, without being a rule itself.
Context Anchor
Pilots and instructors see Advisory Circulars when researching FAA guidance on training, maintenance, operations, airports, aircraft equipment, or safe operating practices.
Derivation
‘Advisory’ comes from the Latin advisare, meaning ‘to consider’ or ‘to give counsel.’ ‘Circular’ originally meant a written notice circulated to many people. Together the term simply means ‘a notice circulated to give advice’ — which is exactly what the FAA uses these documents for.
Why Pilots Care
Advisory Circulars clarify safe operating methods and regulatory interpretations that support better decision-making and compliance during training and flight operations.
Intuition Check
Do not read Advisory Circular as casual advice. In aviation, it means an official FAA guidance document, even though it is usually not a regulation by itself.
Example Sentence 1
The instructor referred to the relevant Advisory Circular for guidance on conducting a flight review.
Example Sentence 2
Pilots often consult an Advisory Circular when seeking recommended procedures for a specific training maneuver.