KEY TAKEAWAYS

✓
NADCAP accreditation is mandatory for most special processes on aerospace and defense hardware — it is not optional when called out on a drawing or PO.

✓
Accreditation is process-specific and commodity-specific — a shop certified for heat treating is NOT automatically certified for NDT or coatings.

✓
NADCAP audits are conducted by PRI (Performance Review Institute) and are far more rigorous than standard ISO or AS9100 audits.

✓
Always verify a supplier’s NADCAP accreditation directly in the eAuditNet database before releasing a purchase order.

✓
If your part requires a NADCAP special process, source it early — lead times for accredited processors can be significantly longer than standard shops.

NADCAP stands for National Aerospace and Defense Contractors Accreditation Program. It is an industry-managed accreditation program administered by the Performance Review Institute (PRI), a not-for-profit organization. NADCAP was established in 1990 to create a single, unified audit standard for special processes used in aerospace and defense manufacturing — replacing the inefficient system where each prime contractor (Boeing, Lockheed, Raytheon, etc.) would independently audit the same supplier shops, often repeatedly and inconsistently.

The core idea is supplier audit harmonization. When a supplier earns NADCAP accreditation for a specific process, that accreditation is recognized by all NADCAP-subscribing prime contractors and government agencies simultaneously. This reduces audit burden on suppliers while raising the overall quality floor across the industry. PRI manages the program under the governance of major aerospace primes and the U.S. Department of Defense, which gives it genuine regulatory weight — not just a voluntary quality badge.

NADCAP is not a product certification and not a company-wide certification. It is a process-specific and commodity-specific accreditation. A supplier can be NADCAP-accredited for chemical processing but not for welding. Always check the specific commodity category before assuming a shop is covered.

NADCAP is NOT a company-wide certification. A supplier certified in one commodity (e.g., heat treating) is NOT certified in others (e.g., NDT). Verify each process independently in eAuditNet.

NADCAP covers what the industry calls special processes — manufacturing operations where the final quality of the output cannot be fully verified by inspection alone. The result is largely dependent on the process itself being executed correctly, with qualified equipment, procedures, and personnel. These are high-stakes processes where an undetected defect can cause catastrophic failure in flight.

The primary NADCAP commodity categories include:

• Heat Treating — stress relieving, annealing, aging, solution treating of metals
• Chemical Processing — anodizing, chromate conversion, passivation, etching, plating
• Non-Destructive Testing (NDT) — fluorescent penetrant inspection (FPI), magnetic particle inspection (MPI), ultrasonic testing (UT), radiographic testing (RT)
• Welding — fusion welding of structural and pressure-containing aerospace hardware
• Coatings — thermal spray, HVOF, plasma spray, and related processes
• Composites — layup, cure, bonding of fiber-reinforced polymer structures
• Fluid Distribution Systems — tube bending, swaging, and assembly for aerospace fluid lines
• Electronics — soldering, conformal coating, and PCB fabrication for aerospace electronics

If any of these processes appear on your engineering drawing, specification, or purchase order for an aerospace or defense application, NADCAP-accredited processing is almost certainly required.

NADCAP audits are performed by PRI-approved industry auditors — typically experienced aerospace engineers who have deep subject-matter expertise in the commodity being audited. Unlike ISO 9001 audits, which tend to assess quality management systems at a relatively high level, NADCAP audits are extremely detailed and technically specific. Auditors use standardized checklists (called Audit Criteria) that drill into equipment calibration records, process specifications, personnel training and qualification records, bath chemistry logs, test result traceability, and much more.

The audit cycle varies by accreditation status. New suppliers typically start with an 18-month accreditation period. Suppliers with strong audit histories can achieve Merit status, which extends the audit interval to 24 or even 36 months. Suppliers with findings or nonconformances may be placed on shorter review cycles or have their accreditation suspended or revoked entirely. Accreditation status is public — every active and lapsed NADCAP accreditation is searchable in PRI’s eAuditNet database at eauditnet.com.

Preparing for a NADCAP audit is a major undertaking. Suppliers must have documented, controlled process specifications that comply with applicable industry standards (such as AMS, MIL-SPEC, or ASTM), qualified and certified personnel, calibrated and maintained equipment, and robust records. Many shops invest months of preparation before their first audit.

Before awarding a PO for any special process, verify accreditation status at eauditnet.com. Accreditations expire. A shop that was certified last year may not be certified today.

AS9100 is a quality management system (QMS) standard. It governs how a company plans, controls, documents, and continuously improves its overall quality processes across the organization. It is broad and system-level — covering everything from supplier management to design control to corrective action processes. AS9100 certification tells you a company has a functioning, audited quality system that meets aerospace industry requirements. It does not tell you anything specific about the technical competency of a particular manufacturing process.

NADCAP, by contrast, is a process-level technical accreditation. It answers a very specific question: does this shop’s heat treating process, or NDT process, or plating process, meet the detailed technical requirements needed to produce aerospace-quality results? The two are complementary, not interchangeable. Many NADCAP-accredited processors also hold AS9100 certification, but neither one substitutes for the other in a prime contractor’s supply chain requirements.

For engineers sourcing aerospace parts: a machine shop can be AS9100-certified and still be completely ineligible to perform NADCAP-required special processes. The correct approach is to flow NADCAP requirements down to the appropriate sub-tier supplier who holds the specific commodity accreditation. This is a common gap in less experienced supply chains — and a common source of NCRs during customer source inspections.

AS9100 = quality management system. NADCAP = technical process accreditation. You need both for most aerospace production programs. They are not interchangeable.

The short answer: when your customer or their flow-down requirements say it is. NADCAP is not a blanket legal requirement for all aerospace manufacturing — it is contractually mandated by the prime contractors and government programs that subscribe to the NADCAP program. In practice, this means virtually all Boeing, Airbus, Lockheed Martin, Northrop Grumman, Raytheon, GE Aerospace, and Pratt and Whitney production programs require NADCAP-accredited processing for applicable special processes.

The requirement is typically communicated in one of three ways: explicitly called out on the engineering drawing or applicable material/process specification, referenced in the purchase order quality clauses, or embedded in the prime contractor’s approved supplier list (ASL) requirements. If you are building to a military specification (MIL-SPEC) or a Federal Aviation Administration (FAA)-related production approval, NADCAP accreditation is frequently required by the underlying process specifications themselves — not just by customer preference.

For research, prototype, and non-flight hardware, NADCAP is often not required. Many programs explicitly allow non-accredited processing for development articles, provided the parts are clearly identified as non-flight hardware. However, once hardware transitions from development to production qualification or flight status, NADCAP requirements typically apply. Verify this transition point explicitly in your program documentation — assuming prototype rules carry forward to production is a costly mistake.

Prototype or R&D hardware often does NOT require NADCAP processing — but confirm this explicitly in your contract and quality plan. Assuming prototype rules apply to production hardware is a common and expensive error.

Finding NADCAP-accredited processors requires going directly to the source. The eAuditNet supplier search at eauditnet.com is the authoritative, real-time database of all active NADCAP accreditations. You can search by commodity, geographic region, and specific process. Always check this database directly rather than relying solely on a supplier’s self-reported certifications — accreditations can lapse, be suspended, or be scoped more narrowly than a supplier’s marketing materials suggest.

When qualifying a NADCAP supplier, request their current accreditation certificate and verify it covers the specific commodity and process you require. Confirm the certificate is current and not in a probationary or suspended status. Ask for their applicable process specification list and verify it includes the specific material and process specifications called out on your drawing (for example, AMS 2750 for pyrometry in heat treating, or AMS 2480 for hard chrome plating). A legitimate NADCAP shop will have these documents immediately available and will be accustomed to providing them.

Nimble’s certified partner network includes suppliers with NADCAP-accredited special process capabilities across heat treating, chemical processing, and NDT. When you submit a part that carries NADCAP requirements, the sourcing team verifies accreditation status and flows the requirements down appropriately — so you are not managing sub-tier compliance manually across multiple vendors.

Poor specification is one of the most common sources of NADCAP-related quality escapes. If your drawing or purchase order does not explicitly call out the NADCAP requirement and the applicable process specification, there is no contractual basis to enforce it — and a non-accredited shop may process your parts without realizing accredited processing was needed.

Best practices for specification include:

• Reference the applicable process specification by number on the drawing (e.g., AMS 2759/1 for low-alloy steel heat treating, or AMS 2470 for anodize). Most NADCAP-required processes have associated AMS, MIL-SPEC, or ASTM specifications that implicitly or explicitly require NADCAP accreditation.
• Add a drawing note or PO quality clause stating: ‘All special processes shall be performed by NADCAP-accredited suppliers for the applicable commodity.’
• List the specific commodity categories required (heat treat, chemical processing, NDT, etc.) so there is no ambiguity about what must be NADCAP-covered.
• Require suppliers to submit a First Article Inspection (FAI) with NADCAP certification documentation included in the data package.

When working with a managed sourcing partner like Nimble, DFM reviews flag specification gaps before parts go to production — catching missing process callouts before they become supplier nonconformances. Getting the drawing right upstream is far less costly than a quality escape downstream.

If your drawing does not explicitly reference a process specification and a NADCAP requirement, your supplier has no contractual obligation to use an accredited processor. Silence on the drawing is not protection.

Even experienced procurement teams run into the same recurring NADCAP compliance problems. Understanding them in advance is straightforward — getting caught by them is expensive.

Pitfall 1 — Assuming accreditation is current. NADCAP certificates expire. A supplier that was accredited when you first qualified them may have lapsed since. Check eAuditNet before every new PO release for a critical special process, or at minimum annually for active suppliers.

Pitfall 2 — Scope mismatch. A supplier accredited for ‘heat treating’ may only be accredited for specific material families (titanium, aluminum, steel) and not others. Verify the scope includes your specific material and specification, not just the broad commodity category.

Pitfall 3 — Flowing down requirements to non-NADCAP sub-tiers. If your machining supplier sub-contracts heat treating or plating to an unaccredited shop, your parts are non-compliant even if your machining supplier holds AS9100 certification. Flow-down clauses and supplier qualification requirements must explicitly address sub-tier NADCAP compliance.

Pitfall 4 — Treating prototype status as permanent. Covered earlier, but worth repeating — development hardware exemptions do not automatically carry into production. Establish a formal design-to-production transition checklist that includes NADCAP compliance review as a required gate.

Scope mismatch is a silent killer. ‘NADCAP Heat Treat accredited’ does not mean accredited for every alloy or specification. Verify the exact AMS or MIL-SPEC coverage before releasing hardware.

READY TO SOURCE?

Table of Contents

Related Services

Get a Quote in 24h

Upload your drawing and get a detailed quote with free DFM review.