What is the designation of the certificate authorizing an operator to conduct specified commercial air transport operations?

The designation of the certificate that authorizes an operator to conduct specified commercial air transport operations is known as an air operator certificate. This certificate is essential as it signifies that the operator is authorized by the relevant aviation authority to engage in commercial air transport activities, ensuring compliance with safety regulations, operational standards, and airworthiness requirements. The issuance of this certificate involves rigorous scrutiny of the operator's capabilities, including their maintenance procedures, operational practices, and the qualifications of their personnel.

In contrast, the other options refer to different types of certifications or permits. An air transport certificate, while a relevant term, does not specifically address the regulatory authorization needed for operators. A certificate of airworthiness pertains to individual aircraft, confirming that they meet safety and operational standards before they can fly. Lastly, the certificate of public convenience and necessity is a regulatory requirement for operators to prove that they are necessary for the transportation services in the area they intend to serve, rather than directly authorizing flight operations. Thus, the air operator certificate stands out as the definitive authorization for commercial air transport.