PPAP (Production Part Approval Process) is the automotive industry's equivalent of the aerospace FAI. Defined by the AIAG PPAP manual (4th edition) and required under IATF 16949, it is a formal process to demonstrate that a supplier can consistently manufacture parts to customer requirements.
Like FAI, PPAP covers dimensional verification of all drawing characteristics, material and performance test results, process capability studies (Cpk), control plans, and process flow diagrams. The submission level (1 through 5) determines what documentation must be submitted to the customer versus retained on-site.
While PPAP and FAI share similar goals, they are not interchangeable. PPAP is automotive-centric (IATF 16949 / AIAG) while FAI is aerospace-centric (AS9102 / EN 9102). Some aerospace customers who also supply automotive markets may encounter requirements for both.
The key structural difference: PPAP requires a full production run (typically 300 consecutive parts) for capability studies, while AS9102 FAI is performed on the first article only.
Concrete example
A tier-1 automotive supplier delivering to both a car OEM and an aerospace prime may need to complete a PPAP for the automotive customer and a separate AS9102 FAI for the aerospace customer — for the same part.