a. Provides information about Title 14, Code of Federal Regulations (14 CFR), part 21, Certification Procedures for Products, Articles, and Parts. (Articles include parts as defined in 14 CFR § 21.1(b)(2)).
b. Provides a means to control products and articles shipped prior to the issuance of a type certificate (TC), a supplemental type certificate (STC), or a production certificate (PC). For the purposes of this AC, the acronym TC includes STC.
c. Is not mandatory and does not constitute a regulation. This AC describes an acceptable means, but not the only means, to comply with these requirements. However, if you use the means described in the AC, you must follow it in all important respects.