14 CFR 21.19 : Aeronautics And Space (§ 1.1 To Parts 1311-1399) — (§ 1.1 To Parts 50-59) — Federal Aviation Administration, Department Of Transportation (§ 1.1 To Parts 50-59) — Aircraft (§ 21.1 To Parts 50-59) — Certification Procedures For Products And Articles (§ 21.1 To § 21.700) — Type Certificates (§ 21.11 To § 21.55) — Changes requiring a new type certificate.

4 Aug 2016

Each person who proposes to change a product must apply for a new type certificate if the FAA finds that the proposed change in design, power, thrust, or weight is so extensive that a substantially complete investigation of compliance with the applicable regulations is required.

14 CFR 21.19
[Doc. No. 28903, 65 FR 36265, June 7, 2000]