FAR 21.191 — Experimental Airworthiness Certificates
FAR 21.191 lists the purposes for which the FAA issues experimental airworthiness certificates, from R&D and air racing to amateur-built and light-sport aircraft.
FAR 21.191 spells out the specific purposes for which the FAA will issue an experimental airworthiness certificate. An aircraft can't just be flown "experimentally" for any reason — it has to fit one of the listed categories, and the operating limitations attached to the certificate will reflect that purpose.
The approved experimental purposes include:
- Research and development — testing new designs, equipment, installations, techniques, or uses.
- Showing compliance with regulations — flights for type certificates, supplemental type certificates (STCs), major design changes, and function-and-reliability testing.
- Crew training for the applicant.
- Exhibition at air shows and film/TV productions, plus practice and ferry flights.
- Air racing, including practice and travel to events.
- Market surveys, sales demos, and customer crew training (per § 21.195).
- Amateur-built (homebuilt) aircraft — built mostly by the owner for education or recreation.
- Primary category kit-built aircraft assembled without the kit manufacturer's supervision.
- Light-sport aircraft meeting specific kit-built or transition criteria.
Why it matters: as a pilot, the experimental purpose drives the operating limitations in the aircraft's documents — what you can do, where, and with whom on board.
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?