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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 H—Airworthiness Certificates (§21.171 to §21.199) > 21.177—Amendment or modification.
21.177—Amendment or modification.
An airworthiness certificate may be amended or modified only upon application to the Administrator.