AS9100 vs. ISO 9001: What Aerospace Suppliers Need to Know

If you manufacture parts for the aerospace supply chain, you've likely run into both standards — and the relationship between them causes real confusion. Here's the short version: AS9100 isn't a replacement for ISO 9001, it's ISO 9001 plus roughly 100 aerospace-specific requirements layered on top.

ISO 9001 is the foundation. ISO 9001 is the internationally recognized, industry-agnostic standard for quality management systems — process control, corrective action, management review, continuous improvement. It applies to virtually any organization, in any industry.

AS9100 builds on it for aerospace. Developed by the International Aerospace Quality Group using ISO 9001 as its base, AS9100 keeps every ISO 9001 requirement and adds aerospace-specific ones: First Article Inspection, key characteristics tracking, counterfeit parts prevention, and a much heavier emphasis on risk management, including formal Failure Mode and Effects Analysis (FMEA) to identify and mitigate potential failure points before they happen.

The supply chain difference. One of the most consequential differences is flow-down. ISO 9001 has general supplier-evaluation requirements, but AS9100's aerospace-specific requirements travel with the part through every tier of the supply chain — not just your direct customer. If you supply an AS9100-certified prime, your own quality system is expected to support those same requirements, whether or not you're AS9100-certified yourself.

For manufacturers weighing whether AS9100 is worth pursuing: if your customers are aerospace primes or OEMs, it's rarely optional in practice, even when it isn't contractually mandatory on paper — and building toward it early is considerably cheaper than retrofitting a quality system under deadline pressure from a new contract.