AS9102 Rev C CNC FAI: Process, Checklists & Compliance

Key Takeaways for AS9102 Rev C CNC FAI

• AS9102 Rev C FAI provides formal, documented verification that the initial CNC-machined aerospace part meets all drawings, CAD models and specifications before full-rate production.
• The three interdependent AS9102 Rev C forms, Part Number Accountability (Form 1), Product Accountability (Form 2) and Characteristic Accountability (Form 3), align with CNC programming, material traceability and dimensional inspection phases.
• A 7-step CNC FAI process covers programming verification, setup and fixture checks, first-piece production, CMM measurement, material traceability, documentation assembly and final approval with retention requirements.
• Common FAI failures arise from datum misalignment, tooling wear, missing special-process evidence, incomplete characteristic capture and thermal distortion, and each issue requires a defined root-cause fix.
• Precision Advanced Manufacturing executes every step of the AS9102 Rev C FAI playbook in-house under AS9100D and ITAR-registered systems; discuss FAI execution for an aerospace CNC program with the team.

The Three AS9102 Rev C Forms in CNC Production

AS9102 Rev C structures every FAI around three interdependent forms. Each form aligns with a specific CNC production phase: Form 1 governs program and drawing verification, Form 2 controls material and process traceability and Form 3 documents dimensional inspection results.

Form 1 — Part Number Accountability captures part number, name, drawing revision, serial or lot identification, FAI status (full, partial or delta) and customer and internal references such as the purchase order or work order. A single signature on Form 1 locks all three forms, replacing the prior requirement for separate sign-offs on each. The total number of design characteristics declared on Form 3 must match the balloon count on the inspection drawing.

Form 2 — Product Accountability records every material specification, lot or heat number, special process (heat treat, NDT, welding, plating, coating) and functional test requirement. Every special process must reference the applicable specification and show the processor’s current Nadcap or customer-approved status. Expired certificates make those entries invalid.

Form 3 — Characteristic Accountability lists every ballooned dimension, tolerance, GD&T frame, surface finish callout and drawing note alongside the measured result, acceptance status, measurement method and operator. On AS9102 Rev C Form 3, the Results column must list numeric measurements for dimensional characteristics but may record attribute results (pass/fail, accept or statement of conformance) when qualified tooling, automated inspection, visual verification or process requirements apply.

Discuss CNC FAI requirements with Precision Advanced Manufacturing for an upcoming aerospace program.

7-Step CNC FAI Process for AS9102 Rev C

1. Programming verification. Confirm the CNC program references the correct drawing revision, datum structure and feature sequence before cutting the first piece. A new CNC program, created due to altered toolpaths, datums or feature relationships, triggers a new FAI.
2. Setup and fixture check. Verify workholding enforces the datum precedence order shown in the feature control frame. CMM fixture design must enforce this datum structure, not approximate it with a convenient surface.
3. First-piece run. Machine the part under production conditions, including production location, equipment, operation sequence, approved sub-tier processors and production material. Prototype or development samples that do not represent the production path must be labeled and receive customer direction.
4. CMM measurement. Run the CMM program against every ballooned characteristic. Retain the program for reuse on subsequent inspection lots to control variables such as probe approach angles and part orientation.
5. Material traceability verification. Confirm the heat or lot number on the physical stock matches the Mill Test Report (MTR), cross-check chemistry and mechanical values against specification limits and attach the MTR to the FAI package.
6. Documentation assembly. Compile Forms 1, 2 and 3 with the ballooned drawing, MTR, special-process certificates, CMM report and any functional test records. Resolve all open nonconformances before submission.
7. Approval and retention. Obtain the Form 1 signature, which locks the full report. Retain the complete package, including the CMM program, for the duration required by AS9100D and applicable contract terms.

CMM Ballooned-Drawing Checklist for AS9102 Rev C

AS9102 Rev C requires a ballooned drawing (or equivalent) to accompany the FAI package so every Form 3 row can be traced to a design characteristic, with the rule located in characteristic-accountability provisions rather than Section 4.1. Submitting an unballooned print triggers automatic rejection.

• Assign sequential balloon numbers to every dimension, tolerance, GD&T frame, surface finish callout, note and title-block callout so the balloon count matches total design characteristics declared on Form 3.
• Confirm datum precedence matches the feature control frame, and verify the CMM fixture and program enforce the same datum structure to keep measurements valid.
• Capture all GD&T callouts, including MMC bonus tolerance application, and document MMC modifiers without leaving any GD&T incomplete.
• Link each Form 3 row to its balloon number, measurement tool ID and operator so every characteristic is traceable to a specific balloon, tool and operator.
• Verify the drawing revision on the ballooned print matches Form 1 and the purchase order to prevent revision mismatch.
• Record numeric measurements for dimensional characteristics on Form 3, and use attribute results only in the qualified cases described in AS9102 Rev C.
• Retain the CMM program for reuse on subsequent inspection lots, since the program controls probe approach angles, datum setup and part orientation.

Material Traceability Checklist for CNC FAI

A part can pass dimensional CMM inspection yet fail FAI if the material certification is missing, the heat treat cycle is undocumented or a special process was performed by an unapproved source.

1. Verify heat or lot number at receiving. Confirm the heat number stamped on the material matches the MTR before logging the stock into the digital tracking system and releasing it for CNC machining.
2. Cross-reference chemistry and mechanical values. Confirm chemistry and mechanical values fall within specification limits and verify the specification revision level matches the drawing.
3. Confirm material source is on the Approved Vendor List. Aerospace suppliers typically maintain an AVL of material sources that meet relevant quality system requirements to reduce the risk of counterfeit or untraceable alloys.
4. Transfer heat or lot markings to cut pieces. When stock is cut into smaller pieces for multiple CNC-machined components, transfer the heat number to each piece before removing the original marking.
5. Attach MTR and special-process certificates to the FAI package. Include the applicable material specification, the MTR or certificate and explicit confirmation that the raw material conforms to requirements, along with special-process certificates when applicable.
6. Confirm Nadcap or customer-approved status for every special process. Include cure charts, pyrometry data, NDT records or plating certifications, not just references.
7. Retain records for the required period. Aerospace traceability records, including MTRs linked to FAI documentation, must be retained for the period required by applicable standards, customer contracts and the organization’s quality management system.

Common CNC FAI Failures and Practical Fixes

Datum misalignment. Datum disputes are the root of most measurement conflicts. The fix is to enforce a 3-2-1 datum strategy in the CMM fixture and verify the CNC program references identical datum targets before the first cut.

Tooling wear and incorrect setup. Incorrect machine setup, worn tooling and fixture drift are process root causes of FAI failure. Corrective action requires producing a new part under modified production conditions, not reworking the failed first article.

Thermal distortion. Heat generated during aggressive CNC operations can shift critical features outside tolerance. Precision welding and machining techniques that limit thermal input, combined with in-process temperature monitoring, reduce this risk on tight-tolerance assemblies.

Missing special-process evidence. Missing special process evidence is a recurring FAI failure mode, occurring when parts sent for heat treat or NDT have the process referenced in the FAIR but lack attached supporting records such as cure charts, pyrometry data or inspection records. The fix is to attach all process evidence before submission.

Incomplete characteristic capture. Notes, general tolerances and material callouts buried in the drawing’s title block are commonly missed during ballooning. Every note and callout must be ballooned and recorded on Form 3.

FAI Triggers When Machines or Processes Change

AS9102 treats a completed FAI as valid only for the specific design-process-location combination under which it was performed. The following changes require a documented FAI review and typically a new or partial FAI.

Triggers for a full FAI:

• First production run of a new part number
• Design change affecting fit, form, function, safety or reliability
• Change in manufacturing source, site or facility
• Major programming or setup strategy changes on CNC or automated equipment
• A production lapse exceeding two years requires an FAI (full or partial) for any characteristics that may be impacted under AS9102 Rev C
• Major nonconformance or systemic process issues showing the original FAI is no longer representative

Triggers for a partial or delta FAI:

• New fixture affecting datum control and repeatability
• New heat-treatment route or coating vendor
• Change in sub-tier supplier for raw material
• Limited engineering change affecting only certain characteristics

Customer contract language and quality clauses take precedence over AS9102 Rev C and can mandate a full FAI at each revision change or add triggers such as new sub-tier suppliers. Document the full-versus-partial FAI determination with a clear rationale before proceeding.

Approval-Packet Assembly Checklist for AS9102 Rev C

• Form 1 signed and dated, with total design characteristic count on Form 3 matching balloon count
• Form 2 complete with all material specifications, lot or heat numbers and special-process references
• Form 3 complete with measurements that follow the numeric-versus-attribute rules described earlier
• Ballooned inspection drawing at the correct revision level matching Form 1 and the purchase order
• MTR attached and heat or lot number verified against physical material
• Nadcap or customer-approved certificates for every special process, with expiration dates confirmed
• CMM report with calibration traceability and measurement uncertainty documentation
• Functional test records where required by design
• Full-versus-partial FAI determination documented with rationale
• All NCRs and MRB dispositions resolved and referenced in the package

Plan an FAI package with Precision Advanced Manufacturing that covers documentation from first cut through final approval.

How Precision Advanced Manufacturing Runs FAI In-House

Precision Advanced Manufacturing consolidates multi-axis CNC machining, precision fabrication, specialty welding, secondary finishing and engineering support under one roof at facilities in California and Texas. That integration reduces handoffs between machine shop, heat treater, plater and inspection lab that create documentation gaps and schedule risk on FAI programs.

The company operates under AS9100D and ISO 9001:2015 certified quality management systems and is ITAR registered. Every production step follows defined quality checkpoints, full material traceability and complete documentation aligned to AS9102 Rev C requirements. In-house CNC programming and tooling development allow the engineering team to verify datum structures, toolpath strategies and fixture designs before the first piece runs.

Supplier quality engineers and program managers gain a single accountable partner for the entire FAI package, including ballooned drawings, CMM reports, MTR verification, special-process certificates and Forms 1 through 3.

Frequently Asked Questions

What triggers a full FAI under AS9102 Rev C for CNC parts?

A full FAI is required for the first production run of a new part number, a design change affecting fit, form, function, safety or reliability, a change in manufacturing source or site, major CNC programming or setup strategy changes, a production lapse exceeding two years requiring an FAI (full or partial) for any characteristics that may be impacted and systemic nonconformances showing the original FAI is no longer representative. Customer contract language and purchase order clauses can add triggers or shorten the production-lapse threshold, and those flowdowns control the requirement in practice.

What is the difference between a full, partial and delta FAI under AS9102 Rev C?

A full FAI covers all design characteristics on the drawing or model and is required when the prior FAI is no longer representative of the production process. A partial FAI applies when a manufacturing process, location, tooling or equipment change affects only a portion of the part and the design data is unchanged, and it must reference the previous full FAI and clearly identify what changed. A delta FAI applies when an engineering change affects only certain characteristics and documents only those affected characteristics while the prior FAI remains the baseline for unaffected features.

Can a part pass CMM inspection and still fail FAI?

A part can pass dimensional CMM inspection and still fail FAI if the material certification is missing, the heat treat cycle is undocumented, a special process was performed by an unapproved source, the drawing revision on the ballooned print does not match the purchase order or the Nadcap certificate for a required process has expired. AS9102 Rev C requires objective evidence across all three forms, and dimensional conformance alone does not satisfy FAI approval.

How long must FAI records and MTRs be retained for aerospace CNC parts?

Aerospace traceability records, including MTRs linked to FAI documentation, must be retained for the period required by applicable standards, customer contracts and quality management system requirements. Customer contracts and program-specific quality clauses may extend this requirement further, and those terms take precedence.

What are the most common reasons an AS9102 Rev C FAI package is rejected?

Common rejection causes include a drawing revision mismatch between the ballooned print and the purchase order, missing or expired Nadcap certifications for special processes, incomplete GD&T recording that omits MMC bonus tolerance application, use of qualitative entries where numeric measurements are required on Form 3, missing special-process evidence such as cure charts or NDT records and absence of a documented full-versus-partial FAI rationale. Submitting an unballooned print or a balloon count that does not match the total declared on Form 3 also triggers automatic rejection.

Conclusion: Coordinated CNC FAI for AS9102 Rev C

Executing AS9102 Rev C FAI on CNC-machined aerospace parts requires precise coordination across programming verification, CMM metrology, material traceability and documentation assembly. Each of the three forms maps to a specific phase of CNC production, and gaps in any area, such as a missing MTR, an expired Nadcap certificate or an unballooned note, cause rejection and program delay.

Precision Advanced Manufacturing’s integrated capabilities, AS9100D and ITAR quality system and in-house engineering support are structured to run every step of this playbook without the handoffs that introduce risk. From ballooned drawing preparation through final approval-packet assembly, the team delivers complete, traceable FAI documentation alongside conforming hardware.

Connect with Precision Advanced Manufacturing to review aerospace CNC FAI requirements for an upcoming program.