- Operating amateur-built aircraft: to operate an amateur-built aircraft in which the major portion has been fabricated and assembled by persons for their own recreation or education.
- Operating kit-built aircraft: to operate a primary category aircraft that was assembled by a person from a kit manufactured by the holder of a production certificate for that kit, without the supervision and quality control of the production certificate holder.
- Operating light-sport aircraft: operating a light-sport aircraft that:
- Has not been issued a U.S. or foreign airworthiness certificate and does not meet the provisions of 14 CFR section 103.1. An experimental certificate will not be issued under this paragraph for these aircraft after January 31, 2008;
- Has been assembled:
- From an aircraft kit for which the applicant can provide the information required by 14 CFR section 21.193(e); and
- In accordance with manufacturer's assembly instructions that meet applicable consensus standard; or
- Has been previously issued a special airworthiness certificate in the light-sport category under 14 CFR section 21.190.
Operating Amateur-built, Kit-built, or Light-sport Aircraft
Special airworthiness certificates may be issued in the experimental category for: