Airworthiness Directives (ADs) are legally enforceable regulations issued by the FAA in accordance with 14 CFR part 39 to correct an unsafe condition in a product. Part 39 defines a product as an aircraft, engine, propeller, or appliance. This manual provides policy and guidance for the drafting, issuance, and distribution of Airworthiness Directives. It is intended to explain the laws that apply to Airworthiness Directives, procedures for writing an Airworthiness Directives, and policies on key Airworthiness Directives-related issues.