FAR 71.51 — Class C Airspace
FAR 71.51 designates Class C airspace areas around primary airports, subject to Part 91 operating and equipment rules. What pilots need to know.
FAR 71.51 is the rule that formally establishes Class C airspace in the United States. Rather than spelling out the boundaries of every Class C area in the regulation itself, the FAA lists them in subpart C of FAA Order JO 7400.11K, which is incorporated by reference into Part 71.
Key points to understand:
- Each Class C area is built around at least one primary airport — typically a moderately busy airport with an operating control tower and approach radar.
- Inside Class C airspace, all aircraft operators must comply with the operating rules and equipment requirements found in Part 91 (such as two-way radio communications, a Mode C transponder, and ADS-B Out).
- The specific dimensions, shelves, and outer limits of each Class C area are published in the FAA Order, and depicted on VFR sectional and terminal charts.
Operationally, this section matters because it tells you where Class C exists and that you must follow Part 91 rules to enter — establishing two-way radio contact with ATC before crossing the boundary is the most common student pilot trip-up.
Five FAA-written-style questions. Instant explanations, every answer cites its source — no account needed.
You are flying VFR in Class E airspace at 8,500 feet MSL during the day. What are your minimum visibility and cloud clearance requirements?