14 C.F.R. § 133.51 Airworthiness certification.
Title 14 - Aeronautics and Space
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]
Title 14: Aeronautics and Space
PART 133—ROTORCRAFT EXTERNAL-LOAD OPERATIONS
Subpart D—Airworthiness Requirements
§ 133.51 Airworthiness certification.
