What is an Advisory Circular (AC) primarily used for by the FAA?

An Advisory Circular (AC) is primarily utilized by the FAA to inform the public about nonregulatory material, providing guidance and clarification on various aviation topics. These publications serve as a means to disseminate information that helps users understand how to comply with existing regulations or best practices without having the force of law. They can cover a wide range of topics, such as operational standards, safety information, and technical guidance, thus assisting pilots and operators in enhancing safety and efficiency in aviation operations.

This function of ACs helps ensure that those in the aviation community have access to valuable insights and recommendations that are not legally binding but are important for effective and safe practices in the field. Other options relate to enforcement or certification processes, which are not the primary role of an AC.