[Code of Federal Regulations] [Title 14, Volume 1] [Revised as of January 1, 2006] From the U.S. Government Printing Office via GPO Access [CITE: 14CFR21.77] [Page 130] TITLE 14--AERONAUTICS AND SPACE CHAPTER I--FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION PART 21_CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS--Table of Contents Subpart C_Provisional Type Certificates Sec. 21.77 Duration. (a) Unless sooner surrendered, superseded, revoked, or otherwise terminated, provisional type certificates and amendments thereto are effective for the periods specified in this section. (b) A Class I provisional type certificate is effective for 24 months after the date of issue. (c) A Class II provisional type certificate is effective for twelve months after the date of issue. (d) An amendment to a Class I or Class II provisional type certificate is effective for the duration of the amended certificate. (e) A provisional amendment to a type certificate is effective for six months after its approval or until the amendment of the type certificate is approved, whichever is first. [Doc. No. 5085, 29 FR 14566, Oct. 24, 1964 as amended by Amdt. 21-7, 30 FR 14311, Nov. 16, 1965]