Aerospace Accreditation Explained: NADCAP, AS9100 and ISO 9001

Aerospace procurement is gated by three accreditations that buyers reference in tenders and suppliers carry on their capability statements: ISO 9001, AS9100, and NADCAP. They are often discussed in the same breath but are not interchangeable, do not certify the same thing, and are not issued by the same body. For procurement teams at GCC airports, airlines, and MROs — and for the regional and international suppliers bidding into them — understanding what each one actually certifies (and, just as importantly, what it does not) determines whether a tender requirement is correctly written, whether a bidder is genuinely qualified, and whether an investment in certification will pay back.

This brief explains each accreditation, how they layer in real aerospace supply chains, how to specify them in a Gulf-market tender, and when a supplier should invest in which.

What Each Accreditation Is and Who Issues It

ISO 9001

ISO 9001 is the generic quality management system (QMS) standard published by the International Organization for Standardization (ISO), based in Geneva. The current revision in force is ISO 9001:2015. It is industry-agnostic: a printer, a logistics firm, a food manufacturer and a metals stockholder can all hold ISO 9001 certification against the same baseline requirements.

The standard defines a process-based QMS built around customer focus, leadership, planning, support, operation, performance evaluation, and improvement. Certification is carried out by accredited third-party registrars (certification bodies) under the oversight of national accreditation bodies — UKAS in the United Kingdom, ANAB in the United States, ENAC in Spain, EIAC and ESMA in the UAE, and so on — all coordinated under the International Accreditation Forum (IAF) for mutual recognition.

In aerospace, ISO 9001 is the floor, not the ceiling. It is assumed of any credible supplier but is not, on its own, sufficient to bid into the supply chains of major airframers or tier-one integrators.

AS9100

AS9100 is the aerospace, defence and space QMS standard maintained by the International Aerospace Quality Group (IAQG) — an industry body whose members include major airframers, engine manufacturers and primes from the Americas, Europe and Asia-Pacific. AS9100 is published as a family of related standards under different designations in different regions (AS9100 in the Americas through SAE International, EN 9100 in Europe through ASD-STAN, JISQ 9100 in Japan), but they are technically identical.

AS9100 incorporates the full text of ISO 9001 and adds aerospace-specific requirements. These cover, among other areas, configuration management, risk management, counterfeit parts prevention, product safety, special-process controls, first-article inspection, supply-chain flow-down of requirements, and traceability obligations far stricter than ISO 9001's baseline.

The current family has three principal variants:

• AS9100D — the QMS for organisations that design and manufacture aerospace, defence or space products.
• AS9110C — the QMS for aviation maintenance organisations (MROs), aligned to the regulatory expectations of EASA Part-145, FAA Part 145, and equivalent national rules.
• AS9120B — the QMS for stockist distributors of aerospace parts and materials, addressing the specific risks of pass-through traceability, repackaging, and counterfeit prevention in the distribution chain.

Certification is performed by IAQG-recognised certification bodies through the Industry Controlled Other Party (ICOP) scheme, which adds aerospace-specific oversight over and above generic ISO/IEC 17021 accreditation. Audits are conducted on a three-year certification cycle with annual surveillance.

NADCAP

NADCAP — the National Aerospace and Defense Contractors Accreditation Program — is administered by the Performance Review Institute (PRI), a not-for-profit affiliate of SAE International based in Warrendale, Pennsylvania. PRI runs NADCAP on behalf of a subscriber group of airframers, engine makers and primes who collectively define the audit criteria.

The defining feature of NADCAP is that it is process-specific, not company-wide. A facility is not "NADCAP certified" as an organisation; rather, individual special processes performed at a specific site are accredited against a published audit checklist. The current NADCAP commodity scope includes, among others:

• Heat treating
• Welding and brazing
• Non-destructive testing (NDT)
• Chemical processing (including anodising, plating and conversion coatings)
• Coatings (thermal spray, paint)
• Composites
• Materials testing laboratories
• Electronics
• Fluid distribution systems
• Aerospace quality systems (a complementary AQS audit programme)
• Sealants
• Fasteners

Audits are conducted by PRI staff auditors against checklists agreed with the subscriber primes, and accreditations are awarded process-by-process with a typical 12- to 24-month renewal cycle depending on the supplier's audit history. The Subscriber Members — Boeing, Airbus, Lockheed Martin, Bombardier, Rolls-Royce, GE Aerospace, Pratt & Whitney, Safran and others — flow NADCAP requirements down to their supply chains and rely on the central audit so that they do not each have to audit every supplier individually.

What Each One Certifies vs Assumes

The three accreditations are not alternatives — they are layered, and each answers a different question.

• ISO 9001 answers: "Does this supplier run a recognisable, documented quality management system?" It is the baseline expectation of any serious B2B supplier in any sector.
• AS9100 answers: "Does this supplier run a QMS that meets the specific risk-management, traceability and configuration-control expectations of aerospace?" It assumes ISO 9001 underneath and adds the sector overlay.
• NADCAP answers: "Has this specific special process, at this specific facility, been audited against industry-agreed technical criteria?" It assumes AS9100 (or an equivalent QMS) underneath and adds a process-level technical stamp.

A supplier holding AS9100D is presumed to satisfy ISO 9001:2015 — the standard is written as a superset. A supplier holding NADCAP accreditations is normally expected to also hold an AS9100-family certification; the NADCAP AQS audit specifically references AS9100 as the underlying QMS.

The mistake to avoid is treating these as substitutes. "We have ISO 9001" does not meet a clause requiring AS9100D. "We have AS9100D" does not satisfy a clause requiring NADCAP welding accreditation. And NADCAP welding accreditation at one site does not extend to a sister site that has not been separately audited.

How They Layer in Real Procurement

In practice, the three standards stack from generic to specific as a contract moves down the supply chain.

A major airframer awarding a structural assembly contract to a Tier 1 aerostructures supplier will typically require that supplier to hold AS9100D at the manufacturing site, and will further require that any special processes in scope (heat treatment of forgings, welding of titanium assemblies, NDT of finished parts, chemical conversion coatings) are NADCAP-accredited, either in-house at the Tier 1 or at sub-tier specialists named in the bill of process. The Tier 1 then flows these requirements down to its own subcontractors via purchase-order quality clauses, so a Tier 3 heat-treat shop in a small industrial town can find itself audited to NADCAP HT criteria because its work ends up on a Boeing or Airbus structure two tiers above.

On the maintenance side, GCC carrier MROs such as Emirates Engineering, Etihad Engineering, Joramco, Oman Air Engineering and Gulf Air Technical Services operate under EASA Part-145 and/or FAA Part 145 approvals for the regulatory side, and typically hold AS9110 as the industry-standard QMS overlay. Their parts suppliers — distributors, OEMs, repair specialists — are expected to hold AS9100D (for manufacturers), AS9120B (for stockist distributors) or AS9110C (for repair stations), with regulatory release documentation (EASA Form 1, FAA 8130-3) on top.

GCC airport infrastructure procurement — the master-plan packages at DXB, AUH, DOH, JED, RUH, MCT and elsewhere — sits in a different category. Baggage handling, screening, ground support equipment, jet bridges, fuel hydrant systems, signage and airfield lighting do not normally trigger NADCAP requirements, because these are not aerospace special-process commodities. They do, however, typically require ISO 9001:2015 as a minimum, with AS9100 or sector-specific equivalents (ISO 14001, ISO 45001) layered in for the more critical packages. Defence-aviation procurement in the region — UAE Ministry of Defence, GAMI in Saudi Arabia, Qatar Armed Forces — follows the prime contractor's flow-down, which is where NADCAP appears, usually via the foreign airframer or systems integrator at the head of the contract.

Buyer-Side Use: How to Specify These in a Tender

For procurement teams writing aerospace tender documents — whether at a GCC airline, MRO, airport authority or defence-aviation buyer — accreditation clauses should be precise, proportionate and technically defensible.

Standard clauses that work well include:

• "Bidder shall hold AS9100D (or EN 9100 / JISQ 9100) certification at the manufacturing location supplying this contract, issued by an IAQG-recognised certification body, and shall provide a copy of the current certificate at bid submission."
• "For MRO services, bidder shall hold AS9110C certification covering the scope of work, in addition to the applicable regulatory approval (EASA Part-145, FAA Part 145, or GCAA CAR-145 as applicable)."
• "Distributors shall hold AS9120B certification covering the product categories supplied under this contract."
• "Where the scope of work includes special processes as defined by the NADCAP commodity list — including but not limited to heat treatment, welding, NDT, chemical processing, and coatings — those processes shall be performed at NADCAP-accredited facilities and the relevant accreditation references shall be provided in the bid."
• "For non-critical commodity items [list], ISO 9001:2015 from an IAF-recognised certification body shall be considered the minimum acceptable QMS."

The pitfall to avoid is over-specification. Requiring NADCAP for processes that PRI does not even audit (machining, assembly, kitting, packaging) is a tender error: it adds nothing to quality assurance, narrows the bidder pool unnecessarily, and signals to experienced suppliers that the buyer does not understand the framework. Equally, applying AS9100 requirements to building-services, commercial-furniture or non-flight-critical infrastructure packages tends to inflate cost without proportionate risk reduction. The right level is the highest level genuinely necessary for the risk class of the goods or service.

Supplier-Side Use: When to Invest in Which

For aerospace suppliers — particularly those building a position in the Gulf market — the certification roadmap follows a clear order of priority.

ISO 9001:2015 is the entry ticket. The investment is modest, certification bodies are easily available in the region (UAE, Saudi Arabia, Qatar and Oman all have an active registrar market under IAF mutual recognition), and the absence of ISO 9001 will eliminate a bidder from almost any serious procurement process. Any aerospace-adjacent business that does not yet hold it should treat it as table-stakes.

AS9100D (or AS9110C / AS9120B as appropriate to the business model) is the highest-leverage single investment for a supplier targeting credible aerospace work. It unlocks bids into prime and Tier-1 supply chains, into GCC carrier MRO panels, and into airport packages where AS9100 is specified. The cost is materially higher than ISO 9001 — both in registrar fees and in the internal QMS rigour required — but the doors it opens are doors that simply do not open without it.

NADCAP is the most specialised investment and should be approached selectively. The annual cost of maintaining a NADCAP accreditation, the technical depth required to pass an audit, and the prime-driven nature of the customer base mean it makes sense only when a supplier already performs one of the NADCAP commodity processes for prime or tier-one customers (or has a credible plan to). For a GCC supplier doing heat treatment, welding, NDT, plating or coatings work for aerospace primes, NADCAP is necessary. For a supplier doing general machining, assembly, distribution or services, NADCAP is the wrong investment and AS9100 is the right one. Pursuing NADCAP without an existing customer mandate is a common — and expensive — strategic mistake.

Closing

For Gulf aerospace buyers, the practical takeaway is that ISO 9001, AS9100 and NADCAP are layered, not parallel — each answers a different procurement question, and tender language should match the actual risk class of the commodity or service being purchased. For suppliers, the order of investment is almost always ISO 9001 first, then the appropriate AS9100-family standard, with NADCAP added only when a specific special-process customer requirement justifies it. Getting this layering right makes tenders cleaner, bids more competitive, and supply-chain qualification faster on both sides of the table.