FAR 91.325 — Primary Category Aircraft

FAR 91.325 sets the rules for how a primary category aircraft (a small, simple aircraft type certificated under a special category) may be operated, especially when money changes hands.

General restriction on compensation or hire. You generally cannot fly a primary category aircraft carrying persons or property for compensation or hire in operations that:

• Require an air carrier or commercial operator certificate under Part 119;
• Are listed in § 119.1(e) (the carve-outs like sightseeing, banner towing, etc.);
• Require fractional ownership management specifications under Subpart K; or
• Are conducted under Part 129, 133, or 137 (foreign air carriers, external load, or agricultural ops).

Pilot-owner maintenance. If the aircraft is maintained by the pilot-owner under an approved special inspection and maintenance program, only the pilot-owner — or a designee, as long as the owner isn't paid for the aircraft's use — may operate it.

Exception for instruction. If the aircraft is maintained instead by a certificated mechanic or repair station under Part 43, it may be used for flight training, checking, and testing for compensation or hire. This matters because it determines whether you can legally rent, instruct in, or carry passengers in this category of airplane.