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CFR > Title 14 - Aeronautics and Space > CHAPTER I—FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION > SUBCHAPTER C—AIRCRAFT (parts 21 to 50) > PART 21—CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS > SUBPART D—Changes to Type Certificates (§21.91 to §21.101) > 21.91—Applicability.
21.91—Applicability.
This subpart prescribes procedural requirements for the approval of changes to type certificates.