Aeroblaze Blog

Advisory Circulars

This month we'll continue discussing the rules, regulations, and guidance material regarding fire testing. Last month we talked about the Code of Federal Regulations (CFR). This month we'll discuss Advisory Circulars.

An Advisory Circular (AC) is a type of publication from the FAA that provides guidance for compliance with regulations such as 14 CFR rules, operating standards, and training standards. They often clarify a regulation or describe best practices. AC's are informative in nature, meaning they are neither binding nor regulatory. They define an acceptable means, but not the only means, of accomplishing or showing compliance with airworthiness regulations. However, they may sometimes describe actions or advice that the FAA expects to be implemented or followed.

AC's can apply to many different aviation personnel, including engineers, mechanics, pilots, and manufacturers. FAA regulations can be complicated and confusing, so AC's give the FAA a way to offer guidelines to the aerospace industry for interpreting regulations and implementing specific activities.

Some common AC's relevant to fire testing are:


  • AC 25-17A: Transport Airplane Cabin Interiors Crash Worthiness Handbook

  • AC 23-2A: Flammability Tests

  • AC 25.853-1: Flammability Requirements for Aircraft Seat Cushions

  • AC 21-25A: Approval of Modified Seating Systems Initially Approved Under a Technical Standard Order (TSO)

All AC's can be found on the FAA's website under Regulations & Policies. Another great resource for Part 25 aircraft is the List of Part 25/26 Rules & Their Associated AC's and Policy Statements. This list contains the 14 CFR 25 & 26 rules and the Advisory Circulars and Policy Statements associated with each rule.

For additional questions, feel free to contact us! Next month we'll cover Policy Statements & Memos.

Back to blog