Definition
The section of the federal aviation regulations that sets the rules for marking and identifying aircraft, including the display of nationality and registration marks (the N-number on U.S. aircraft) and the required identification plate.
Plain English
The rulebook section that says how an aircraft must be marked and identified, including the size, location, and form of its registration number on the outside of the aircraft.
Context Anchor
Seen in FAA discussions of aircraft registration, required markings, identification plates, and aircraft airworthiness paperwork.
Derivation
CFR stands for Code of Federal Regulations. Title 14 covers Aeronautics and Space. A 'part' is a numbered chapter within that title. So '14 CFR part 45' means Title 14, Part 45 of the federal rulebook.
Why Pilots Care
Aircraft must carry correct markings to remain airworthy and avoid enforcement action during ramp checks or ramp inspections.
Intuition Check
“Part” does not mean a physical aircraft part here. In this term, “part” means a numbered section of federal aviation rules.
Example Sentence 1
Before painting his Cessna, the owner checked 14 CFR part 45 to confirm the required size and placement of the N-number.
Example Sentence 2
During preflight, the pilot checked that the N-number placement complied with 14 CFR part 45 requirements.