First Article Inspection (FAI) for Aerospace Parts: What It Includes
First article inspection (FAI) for aerospace parts: what it includes. AS9102 requirements, documentation, and what buyers should expect from suppliers.
First Article Inspection (FAI) for Aerospace Parts: What It Includes
First article inspection is the formal, documented verification that a production process produces a part meeting every requirement on the engineering drawing and associated specifications. In aerospace and defense manufacturing, FAI is not optional—it is a contractual requirement governed by AS9102 and enforced through quality system audits, customer source inspections, and NADCAP assessments.
Yet FAI remains one of the most frequently misunderstood and poorly executed quality activities in the supply chain. Incomplete FAI packages delay shipments, trigger customer rejections, and create audit findings that can suspend a supplier's approved status. This guide explains what FAI includes, how to prepare a compliant package, and where the common failure points are so engineering and procurement teams can set clear expectations and avoid costly rework.
What FAI Is and Why It Exists
FAI answers one question: does the production process, as actually executed, produce a part that meets every requirement? It is not a prototype inspection, not a receiving inspection, and not a statistical process study. It is a complete, one-time verification of every characteristic on the drawing, performed on a part manufactured using the production-intent tooling, equipment, processes, and personnel.
FAI exists because aerospace parts are produced in relatively low volumes where statistical process control (SPC) may not be practical, design requirements are complex (hundreds of dimensions, multiple material specifications, numerous special processes), and the consequences of a nonconforming part reaching service can be catastrophic. By verifying every requirement on the first production article, FAI creates a baseline that subsequent production can be measured against.
The governing standard is AS9102 (Aerospace First Article Inspection Requirement), currently at Revision C. AS9102 defines the forms, content, and documentation requirements for FAI across the aerospace industry. Most prime contractors and government programs flow AS9102 down to their supply chains as a mandatory requirement.
The Three AS9102 Forms
AS9102 structures FAI documentation into three standardized forms that together provide complete traceability from the part number to every individual requirement.
Form 1: Part Number Accountability
Form 1 is the header that identifies the part and the FAI scope. It captures: part number and revision level, part name, serial number of the FAI article, drawing number and revision, the reason for FAI (new part, design change, process change, etc.), the organization performing FAI, and identification of any partial FAI (if the full FAI is being completed in stages).
Form 1 also identifies the FAI completion date and the signature/approval of the responsible quality representative. For assemblies, Form 1 lists each sub-component with its own FAI status (completed, existing, or not required).
Form 2: Product Accountability—Raw Material, Specifications, and Special Processes
Form 2 documents every material, specification, and special process called out on the drawing or in the technical data package. This form verifies that the correct materials were used, the correct processes were applied, and each was performed by an approved source.
Materials are listed with their specification (e.g., AMS 4999 for Ti-6Al-4V, AMS 5662 for Inconel 718), the actual material certificate/lot number, and verification that the material meets the specification. For titanium powder used in additive manufacturing, this includes powder chemistry, particle size distribution, and lot traceability.
Specifications include material specs, process specs (heat treat, HIP, plating, coating), and any customer-specific requirements. Each is listed with the specific revision and verification method.
Special processes (heat treatment, HIP, welding, brazing, NDE, plating, coating) must be performed by approved sources. Form 2 records the process specification, the performing facility, their approval status (NADCAP accreditation number, customer approval letter, or quality system certification), and objective evidence (furnace charts, process records, test reports).
Form 2 is where most FAI packages fail. Missing material certificates, expired NADCAP accreditations, wrong specification revisions, and absent special-process records are the most common deficiencies found during customer review.
Form 3: Characteristic Accountability
Form 3 is the heart of FAI: every dimensional, surface finish, material property, and functional requirement on the drawing is listed with its nominal value, tolerance, and actual measured result. This is the "ballooned drawing" concept—each requirement is numbered (ballooned) on the drawing, and Form 3 records the measured value for each balloon number.
Dimensional characteristics are measured using calibrated equipment (CMM, optical, manual gages) traceable to national standards. The measurement method must be capable of measuring the tolerance—a gage R&R study or equivalent capability evidence may be required for critical dimensions.
Surface finish requirements (Ra, Rz) are measured with calibrated profilometers on the specified surfaces. For additively manufactured parts, both as-built and machined surface roughness values may be required.
Material and mechanical property requirements (hardness, tensile strength, elongation) are recorded from test reports on the FAI article or its associated test coupons. The test method, specimen identification, and results must be traceable to the specific FAI part.
Functional and visual requirements (threads, assemblability, cosmetic appearance, marking) are verified and recorded as conforming or nonconforming. Any nonconformance must be dispositioned through the formal MRB (Material Review Board) process before the FAI can be approved.
Common FAI Failure Points
Based on industry experience, the most frequent causes of FAI rejection include:
Incomplete Form 2. Missing material certs, expired process approvals, or specifications listed at the wrong revision. The fix is a pre-FAI checklist that cross-references every drawing callout against available documentation before the FAI article is even built.
Ballooning errors. Dimensions on the drawing that are not captured on Form 3, or characteristics that are ballooned but not measured. Every requirement—including notes, general tolerances, and reference specifications—must be accounted for.
Measurement uncertainty. Using measurement equipment that cannot adequately resolve the tolerance. As a rule of thumb, measurement uncertainty should be no more than 10% of the tolerance band (10:1 rule). For tight tolerances on complex AM features, this may require CMM rather than manual measurement.
Non-production conditions. The FAI article was not manufactured using production-intent processes. If the FAI part was made on a different machine, with different tooling, or by a different operator than production will use, the FAI is not representative and will likely be rejected.
Undocumented nonconformances. Features that are out of tolerance but not formally dispositioned. Even minor nonconformances must go through MRB with documented rationale and customer approval (if required by contract).
FAI Considerations for Additively Manufactured Parts
Additive manufacturing introduces additional complexity to FAI because the manufacturing process creates the material simultaneously with the geometry. This means Form 2 must capture AM-specific documentation that does not exist in conventional manufacturing.
AM-specific Form 2 entries include: powder specification and lot certificate (chemistry, PSD, flowability), machine identification (serial number, qualified parameter set), build file and parameter set revision, powder reuse history for the build, stress relief furnace chart, HIP cycle record (temperature, pressure, time, cooling rate per PM-HIP specification), heat treatment furnace chart, and any in-process monitoring data if required by the qualification plan.
Form 3 for AM parts must address features that may not exist on conventional parts: as-built surface roughness on specified surfaces, minimum wall thickness verification (often via CT scanning), internal channel dimensions and depowdering verification, and witness coupon test results (tensile, microstructure, density) traceable to the specific build.
For complex AM parts with internal features that cannot be accessed by conventional measurement, CT scanning data may substitute for CMM measurement on Form 3, provided the CT system is calibrated, the measurement uncertainty is documented, and the customer has approved CT as an acceptable measurement method.
Partial FAI and Delta FAI
AS9102 allows partial FAI when only specific characteristics are affected by a change. This is common when a drawing revision changes a few dimensions but does not alter the overall manufacturing route. Partial FAI re-verifies only the changed characteristics, referencing the original full FAI for unchanged features.
Partial FAI is also used when an FAI is performed in stages—for example, verifying material and process characteristics (Form 2) during manufacturing, and completing dimensional verification (Form 3) after final machining. The FAI is not considered complete until all three forms are finalized and approved.
Triggers for new FAI include: new part number or first production, design change affecting form/fit/function, manufacturing process change (new machine, new process route, new facility), extended production break (typically >2 years, though customer requirements vary), and loss of traceability or nonconformance that calls into question the validity of the previous FAI.
How Metal Powder Supply Supports Your FAI Requirements
A complete FAI starts with complete material documentation. Metal Powder Supply provides titanium, tungsten, molybdenum, tantalum, and niobium powders with full lot traceability, certified chemistry, and particle size distribution data that feeds directly into your AS9102 Form 2.
As a DFARS-compliant, AS9100D-certified, ITAR-registered supplier, our documentation meets the requirements that prime contractors and government auditors expect to see in the material certification section of your FAI package.
Request a quote or contact our technical team to discuss powder requirements and documentation needs for your qualification program.
Explore Our Capabilities
Learn more about how Metal Powder Supply supports aerospace and defense manufacturing:
Need a quote or have questions about your project? Request a quote or contact our team to discuss your requirements.
Frequently Asked Questions
Define coupon strategy at contract review and lock it into the router: coupon geometry, build location/orientation, post-processing lot/charge linkage (stress relief/HIP/heat treat), and identification/serialization. If mechanical properties are required, test specimens should be traceable to the same powder lot and build ID as the part, processed in the same HIP/heat treat charge, and recorded with clear ties to the part serial/lot in the FAI package. Document any specimen machining, test standards, lab accreditation requirements, and acceptance criteria in the FAI evidence set.
Select inspection methods that can demonstrate capability relative to tolerance—commonly by showing calibration status, stated instrument uncertainty, and (where required) gauge repeatability and reproducibility (GR&R) or CMM/scanner verification results. For critical GD&T, document datum simulation, fixturing, alignment strategy, and reporting resolution. Include uncertainty statements or method qualification records when the tolerance-to-uncertainty ratio is tight, and ensure the measurement plan is consistent across FAI and production to avoid approval disputes.
Use a controlled record index that maps each ballooned characteristic to a specific evidence artifact (report ID, page/feature, chart ID, NDE report) and store it under configuration control tied to the part revision and serial/lot. Retain the minimum required by contract and QMS: router/traveler, material certs/CoCs, special process charts, inspection/NDE reports, and NCR dispositions. Ensure record integrity via access control, revision history, and consistent identifiers across systems (ERP/MES/QMS) so an auditor can trace from PO and drawing revision to the as-built route and objective evidence.
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