Definition
Three sections of Title 14 of the Code of Federal Regulations that, taken together, establish much of the legal framework governing U.S. airspace and pilot conduct. Part 71 designates and describes the classes of airspace (Class A, B, C, D, E, and G) and other defined areas such as federal airways. Part 73 establishes Special Use Airspace, including Restricted Areas and Prohibited Areas. Part 91 sets the General Operating and Flight Rules that pilots must follow, including the specific operating requirements that apply within each class of airspace.
Plain English
These are three sets of federal aviation rules. One defines what kinds of airspace exist, one defines special restricted zones, and one tells pilots how they must fly in each of them.
Context Anchor
Seen in FAA handbooks, regulations, airspace study, preflight planning, and discussions of what rules apply to a flight.
Derivation
CFR stands for Code of Federal Regulations, the official compilation of U.S. government rules. Title 14 is the volume covering Aeronautics and Space. The numbered 'parts' are simply chapters within that title — Part 71 covers airspace designation, Part 73 covers special use airspace, and Part 91 covers general flight rules.
Why Pilots Care
Knowing these parts ensures pilots understand legal airspace boundaries and operating requirements to fly safely and avoid violations.
Analogy
Think of Title 14 as a large rulebook for aviation. Parts 71, 73, and 91 are like three different chapters in that rulebook, each covering a different subject.
Intuition Check
Part does not mean an aircraft component here. In this context, part means a numbered section of federal aviation regulations.
Example Sentence 1
The classes of airspace shown on a sectional chart are designated under 14 CFR Part 71, while the rules for operating in them are found in Part 91.
Example Sentence 2
A preflight review of 14 CFR parts 71, 73, and 91 helps confirm compliance before entering controlled airspace.