Airworthiness Directives
Airworthiness directives (ADs) are used to communicate unsafe operating conditions related to aircraft and aircraft equipment.
They are mandatory in nature and must be complied with for aircraft to remain airworthy.
There are two types of ADs:
- Emergency issue: Addressing a urgent, safety-of-flight issue
- Normal issue: Less urgent issue, usually requires compliance within a specified period
Special Airworthiness Information Bulletins
Special Airworthiness Information Bulletins (SAIBs) are alerts and reccomendations published by the FAA. They are non-regulatory in nature, and do not meet the criteria for an AD.