Airworthiness Directive (AD)

Airworthiness Directives (AD) are notifications or warnings to the owners and operators of a certified aircraft that there is a known safety deficiency associated with the aircraft. This deficiency could be on the body, engine, avionics, or other systems on the aircraft. When there is an outstanding airworthiness directive present on an aircraft, that aircraft is considered not airworthy (violation of 14 CFR part 39.7). Also contained in an AD is a date or aircraft flying hours which mandates that the owner must comply with the directives by that certain time or total hour.