The production part approval process is the standardized method a supplier uses to prove it can consistently manufacture a part that meets every engineering drawing and specification requirement, submitting a documented package of evidence for customer approval before any part ships from full production. It answers one question for the customer: can you make this part right, every time, at rate?
In the aerospace and manufacturing quality systems we build for clients, PPAP is where planning stops being theory and becomes proof a customer will actually sign off on. A clean submission shortens the approval cycle. A weak one triggers rejections, resubmissions, and delayed launches that cost real money.
Key takeaways
- PPAP is the documented proof that a supplier can make a part to spec before mass production is authorized.
- There are 5 submission levels, from a warrant only up to full documentation retained at the customer site.
- The standard AIAG PPAP defines 18 elements, and the customer sets which ones must be submitted.
- PPAP is the output stage of APQP, and in aerospace it is governed by the AS9145 standard.
What is the production part approval process?
The production part approval process is a supplier qualification protocol first standardized by the Automotive Industry Action Group (AIAG) and now used across aerospace, defense, and general manufacturing. The supplier runs a significant production run, measures the parts, and assembles a package of records that demonstrates the manufacturing process is capable and repeatable. The customer reviews that package and either approves the part for production, approves it on an interim basis, or rejects it.
PPAP is required whenever a part is new, when a design or process changes, when tooling is moved or refurbished, or when a source of supply changes. It is not a one-time formality. Each qualifying change can trigger a fresh submission.
Can you explain the 18 elements of the production part approval process?
The standard AIAG PPAP is built on 18 elements. Together they form the evidence package. The customer decides which elements must be physically submitted and which are simply retained by the supplier and available on request.
- Design records (the released drawing or model)
- Engineering change documents
- Customer engineering approval, where required
- Design Failure Mode and Effects Analysis (DFMEA)
- Process flow diagram
- Process Failure Mode and Effects Analysis (PFMEA)
- Control plan
- Measurement System Analysis (MSA) studies
- Dimensional results
- Records of material and performance test results
- Initial process studies (capability, such as Cpk)
- Qualified laboratory documentation
- Appearance Approval Report (AAR), when applicable
- Sample production parts
- Master sample
- Checking aids
- Customer-specific requirements
- Part Submission Warrant (PSW)
The Part Submission Warrant is the cover sheet that ties the whole package together and records the supplier’s declaration that the parts meet requirements. Two of these elements, the DFMEA and PFMEA, come straight out of upstream planning. If you want a deeper look at that risk analysis, see our guide to PFMEA.
What are the 5 levels of PPAP?
PPAP submissions are graded into five levels. The level sets how much of the package the customer wants to see, not how much work you do. A capable supplier still generates every element internally regardless of level.
| Level | What the supplier submits | Typical use |
|---|---|---|
| Level 1 | Part Submission Warrant only (plus appearance report if needed) | Low-risk, catalog, or proven parts |
| Level 2 | PSW with product samples and limited supporting data | Established supplier, moderate risk |
| Level 3 | PSW with product samples and complete supporting data | Most common default for new parts |
| Level 4 | PSW and other requirements defined by the customer | Customer-specific mix |
| Level 5 | PSW with samples and full data reviewed at the supplier site | High-risk, safety, or new supplier |
Level 3 is the practical starting point for most new parts. When a customer does not specify a level, plan for Level 3 and confirm before you build the package.
PPAP vs APQP: how the production part approval process fits
People often confuse the two. APQP, Advanced Product Quality Planning, is the full front-end framework that plans a product from concept through launch. PPAP is one stage inside it. Think of APQP as the whole road and PPAP as the tollgate near the end where the customer confirms you are ready to ship. The FMEAs, process flow, and control plan you build during APQP become the very elements you submit at PPAP. You can read our full breakdown of the planning framework in our APQP guide.
The OQS PPAP readiness checklist
Over 300 completed projects, the same gaps sink first submissions. Run this short check before you send anything to a customer.
- Confirm the submission level in writing. Never assume Level 3. A single email prevents a full rebuild.
- Verify your dimensional results trace to the current released drawing revision, not a superseded one.
- Make sure your PFMEA, process flow, and control plan agree with each other. Auditors read them side by side, and mismatches are the fastest rejection.
- Run capability studies on the significant characteristics the customer flagged, and hit the required Cpk before you submit, not after.
- Sign the Part Submission Warrant only when every referenced element actually exists and matches. The warrant is a declaration, and it is the first thing reviewed.
PPAP in aerospace: AS9145
Aerospace runs its own version. AS9145 aligns APQP and PPAP for the aviation, space, and defense supply chain, published through SAE International and adopted by primes and their suppliers. It keeps the familiar structure, the FMEAs, control plan, and Part Submission Warrant, but layers in the traceability, configuration control, and first article expectations that aerospace demands. If your customer holds AS9100 certification, expect AS9145-based PPAP flowed down to you as a contract requirement. The AIAG reference remains the baseline, while AS9145 is the aerospace overlay. Building that capability is part of our advanced aerospace standards consulting work.
Production part approval process FAQ
What are PPAP approval steps? In sequence: confirm the trigger and submission level, run a significant production run, complete measurements and capability studies, assemble the required elements, sign the Part Submission Warrant, submit to the customer, and hold production until you receive full approval. Interim approval lets you ship for a limited time or quantity while you close an open item.
Who approves a PPAP submission? The customer’s quality or supplier quality engineering function reviews the package and grants approval, interim approval, or rejection. The supplier cannot self-approve.
How long does the production part approval process take? It depends on part complexity, the submission level, and how clean your data is. A well-prepared Level 3 package can be reviewed in days. Missing or inconsistent records are what stretch approval into weeks.
Do I need PPAP if only my process changed? Usually yes. Process changes, tooling moves, and new sub-suppliers are common triggers even when the design is untouched. When in doubt, notify the customer and let them set the level. If you want that requirement mapped for your specific parts, contact our team.
Preparing a PPAP submission for an aerospace or defense customer?
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