Stages of Involvement (SOI) Audits

Section 04: Certification Process Mechanics

Definition

A structured, stage-based framework used by the FAA to define the authority's oversight and involvement at key milestones during a certification project. The SOI framework divides the certification process into defined stages, and at each stage the FAA performs evaluations, audits, or reviews to assess the applicant's progress, the adequacy of processes, and the quality of compliance data. The SOI approach enables the FAA to calibrate its level of involvement based on the applicant's demonstrated capability and the risk profile of the project.

Where This Shows Up

The SOI audit concept was introduced as part of the FAA's shift toward systems-based oversight, where the focus is on evaluating the applicant's processes and systems rather than reviewing every individual compliance document. Higher-capability applicants (e.g., ODA holders) may have reduced FAA involvement at certain stages, while novel or higher-risk projects receive more intensive stage reviews.

Primary Sources

FAA Order 8110.4, Chapter 3 — Stages of InvolvementFAA

FAA procedures for stage-based involvement in certification projects.

Related Terms

Need help navigating certification?

Understanding the terminology is the first step. If you need expert guidance on DO-178C, DO-254, ARP4754B, or any aspect of FAA, EASA, or TCCA certification, our team is here to help.