- Service Bulletins Related to Airworthiness Directives and Indicating FAA Approval on Service Documents
- Date issued
- Office of Primary Responsibility
This advisory circular (AC) presents best practices for drafting service bulletins (SB) related to an airworthiness directive (AD). This AC also provides information and guidance on ex parté communication and alternative methods of compliance (AMOC), as well as means for avoiding overlapping and conflicting actions in SBs and maintaining airworthiness of AD-mandated design changes. This revision, AC 20-176A, includes guidance for indicating FAA approval on a service document.
- AC 20-176A (PDF)