Definition
The Code of Federal Regulations is the official compilation of the permanent rules issued by the executive departments and agencies of the U.S. federal government. It is organized into 50 numbered titles by subject area. Aviation rules are contained in Title 14, which covers aeronautics and space, and includes the parts that govern pilot certification, aircraft operation, airworthiness, and air traffic procedures.
Plain English
The CFRs are the official written rulebook of the U.S. federal government. Aviation has its own section of that rulebook (Title 14), and that is where the rules pilots have to follow live.
Context Anchor
Seen in FAA handbooks when a topic has legal requirements in addition to flying technique, such as equipment, training, or operating limits for intentional spins.
Derivation
Code here means an organized, written collection of laws — from the Latin codex, a bound book of writings. Federal refers to the national U.S. government. So the term simply means the bound, organized collection of federal rules.
Why Pilots Care
Compliance with the applicable CFRs determines whether a maneuver or operation is legal; failure to follow them can lead to certificate suspension or enforcement action.
Intuition Check
Do not treat CFRs as advice or general guidance. CFRs are enforceable rules; FAA handbooks help explain flying, but the CFRs state the legal requirements.
Example Sentence 1
Before performing intentional spins, the pilot reviewed the relevant CFRs to confirm the aircraft was approved for that maneuver.
Example Sentence 2
A pilot planning a cross-country flight reviewed the CFRs covering fuel reserves and alternate airport requirements.