Definition
A specific paragraph of the Federal Aviation Regulations that prohibits VFR flight beneath a ceiling of less than 1,000 feet within the airspace of an airport with an operating control tower located in Class E surface area, Class D, or Class C airspace. It is one of the basic VFR weather minimum rules that determines when a pilot may legally operate under Visual Flight Rules near towered airports.
Plain English
A short rule in the federal aviation regulations that says: if you are flying VFR near a towered airport, you cannot fly below the cloud base when that cloud base is less than 1,000 feet above the ground.
Context Anchor
Seen when studying basic VFR weather minimums, especially for deciding whether an airport is usable for a normal VFR departure, arrival, or pattern operation.
Derivation
CFR stands for Code of Federal Regulations. Title 14 covers Aeronautics and Space, part 91 covers General Operating and Flight Rules, section 91.155 covers Basic VFR Weather Minimums, and the (c) is the third lettered paragraph within that section. The numbering scheme lets pilots and inspectors point to one exact sentence in a very large rulebook.
Why Pilots Care
Violating this rule risks flying into reduced visibility or terrain hazards near airports.
Analogy
Think of the citation like a street address for a rule: Title 14 is the city, part 91 is the neighborhood, section 91.155 is the building, and paragraph (c) is the specific room.
Intuition Check
Do not read this as just a random legal reference. It points to a specific VFR weather rule: below a 1,000-foot ceiling, normal VFR flight under that ceiling is not allowed in certain airport-controlled airspace.
Example Sentence 1
The instructor pointed out that with the ceiling reported at 800 feet, 14 CFR part 91, section 91.155(c) prohibited their planned VFR departure from the towered airport.
Example Sentence 2
The instructor explained that 14 CFR part 91, section 91.155(c) keeps VFR traffic clear of low ceilings near busy airports.