14 CFR · Part 21
14 CFR § 21.113
Requirement for supplemental type certificate.
If a person holds the TC for a product and alters that product by introducing a major change in type design that does not require an application for a new TC under § 21.19, that person must apply to the FAA either for an STC, or to amend the original type certificate under subpart D of this part.
If a person does not hold the TC for a product and alters that product by introducing a major change in type design that does not require an application for a new TC under § 21.19, that person must apply to the FAA for an STC.
The application for an STC must be made in the form and manner prescribed by the FAA.
Referenced By
Interpretations of This Section (4)
Advisory Circulars (1)
Information for Operators (InFO) (2)
Documents that cite this section, found in their catalog metadata or text. Listed by date, not by significance.
Regulations Referenced
Reflects the eCFR edition current as of September 29, 2026. Retrieved from ecfr.gov on October 16, 2026.
Primary Source