[Code of Federal Regulations] [Title 14, Volume 2] [Revised as of January 1, 2003] From the U.S. Government Printing Office via GPO Access [CITE: 14CFR133.51] [Page 648] TITLE 14--AERONAUTICSAND SPACE CHAPTER I--FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PART 133--ROTORCRAFT EXTERNAL-LOAD OPERATIONS--Table of Contents Subpart D--Airworthiness Requirements Sec. 133.51 Airworthiness certification. A Rotorcraft External-Load Operator Certificate is a current and valid airworthiness certificate for each rotorcraft type certificated under part 27 or 29 of this chapter (or their predecessor parts) and listed by registration number on a list attached to the certificate, when the rotorcraft is being used in operations conducted under this part. [Doc. No. 24550, 51 FR 40709, Nov. 7, 1986]