A first article inspection is the gate between “we think the process is right” and “we have proved it, feature by feature, before the lot runs”. In aerospace it is not a courtesy: AS9102 makes it a contractual deliverable with a defined form set, and Revision C has been in force since June 2023.
This guide is written for the buyer who has to accept or reject the package. It covers what AS9102 actually requires, what triggers a full or partial FAI, what should arrive with the parts, and how to read the file well enough to sign it — or send it back.
Key takeaways
- AS9102 Rev C, released 23 June 2023, defines three forms: Form 1 part number accountability, Form 2 product accountability for materials, special processes and functional testing, and Form 3 characteristic accountability.
- Rev C made Form 1 field 14, “reason for full or partial FAI”, mandatory, removed the signature blocks from Forms 2 and 3, and separated the reviewer roles so the same person should not both prepare and approve.
- An FAI is triggered by a new part number, a design change affecting form, fit or function, a change of source, process, tooling, location or NC program, an event affecting the process, and a production lapse of two years.
- Every characteristic on the drawing must be ballooned and accounted for on Form 3. A report with fewer rows than the drawing has characteristics is incomplete, not concise.
- The gauge listed against a characteristic must be able to resolve it. A caliper reading to 0.01 mm cannot prove a ±0.01 mm band — the worked example below shows the arithmetic.
- MW+ ships a certificate of conformity, a CMM inspection report and material certificates with every order; FAI to AS9102 and PPAP Level 3 are quoted per programme on request.
- What does AS9102 actually require of a first article inspection?
- What triggers an FAI, and when is a partial FAI enough?
- The three AS9102 forms, and what each one proves
- What should actually arrive with the parts?
- Worked example: does the gauge on Form 3 prove the tolerance?
- How do you accept or reject an FAI package?
- FAI, PPAP, in-process inspection or a CMM report: which do you need?
- Which sectors treat FAI as contractual rather than optional?
- When is a full FAI the wrong thing to ask for?
- How MW+ runs first article inspection
- Frequently asked questions
What does AS9102 actually require of a first article inspection?
A first article inspection is a documented verification that a production process, using production tooling, production people and production methods, produces a part that meets every requirement on the drawing and the purchase order. The emphasis is on the process, not the part: the part is evidence, the process is the subject.
That distinction matters commercially. A part measured off a hand-tuned setup by the best operator on day shift proves nothing about the lot. AS9102 therefore requires the first article to be produced under the same conditions the production run will use, and requires the report to record which process produced it.
The standard sits inside the aerospace quality system defined by AS9100D, which builds on ISO 9001:2015. AS9100D requires the organisation to maintain first article inspection; AS9102 defines the form it is reported in, so customer, prime contractor and auditor read the same structure.
What triggers an FAI, and when is a partial FAI enough?
Buyers often assume FAI applies only to the first order ever placed. It does not. The trigger list is about change, and a change at the supplier can require a new FAI on a part you have bought for years.
| Trigger | Full or partial | What the buyer should do |
|---|---|---|
| First production run of a new part number | Full | Require FAI on the purchase order, not after delivery |
| Design change affecting form, fit or function | Partial, covering affected characteristics and anything the change influences | Send the revised drawing and state the revision on the PO |
| Change of manufacturing source, location or supplier | Full | Treat as a new qualification even for an unchanged drawing |
| Change of process, tooling, fixture or NC program | Partial or full depending on reach | Ask which characteristics the supplier judged affected, and why |
| Event adversely affecting the process | Partial or full | Ask for the containment record alongside the FAI |
| Lapse in production of two years | Full | Check the date of the last delivery before reordering |
| Corrective action closing a previous failed FAI | Partial on the failed characteristics | Require the nonconformance record with the re-issued report |
The practical risk sits in the middle rows. A supplier that moves a job from a 3-axis to a 5-axis machine, or re-posts the NC program, has changed the process; if nobody raises a partial FAI, the first evidence arrives with the parts. Putting the trigger list into the purchase order is the cheapest control a buyer has.
The three AS9102 forms, and what each one proves
Rev C keeps the three-form structure and tightens the accountability around it. A complete report is all three forms plus attachments; a PDF of measured dimensions is not an AS9102 FAI, whatever it is called.
| Form | Title | What it records | Rev C change to watch |
|---|---|---|---|
| Form 1 | Part number accountability | Part and drawing numbers, revision, purchase order, part type, assembly bill of materials, reason for the FAI, the prepared-by and approved-by roles | Field 14 reason for full or partial FAI is now mandatory; field 17 changed from part serial number to part type; all BOM parts in an assembly must be listed |
| Form 2 | Product accountability | Materials, special processes and functional testing, with certificate references and the approving authority for each special process | Signature block removed; accountability now closes on Form 1 |
| Form 3 | Characteristic accountability | Every ballooned characteristic with its requirement, the result, the tooling or gauge used, and any nonconformance reference | Signature block removed; nonconformance disclosure is declared on Form 1 field 19 |
Two Rev C changes matter to a buyer. The reviewer separation: whoever prepared the report should not be whoever approved it. And field 19 forces the supplier to declare on the front page whether the report contains a documented nonconformance — previously answerable by burying the detail on Form 3.
What should actually arrive with the parts?
An FAI package is a file, not a certificate. Below is what a complete one contains and what each element proves. Ask for anything missing before the parts go into stores; once they are consumed, the incentive to reconstruct the record disappears.
| Document | What it proves | Common failure |
|---|---|---|
| Forms 1, 2 and 3, completed | The FAI was performed to AS9102 and is accountable | Measured-dimension report supplied in place of the forms |
| Ballooned drawing | Every characteristic is numbered and traceable to a Form 3 row | Balloons applied to only the toleranced features |
| Material certificate with heat or lot number | The material matches the specification and is traceable | Certificate for the grade but not the heat |
| Special process certifications | Heat treat, plating, NDT performed by an approved source | A process performed in-house with no approval reference |
| Functional or performance test results | The part does what the specification says, where called | Test called on the drawing and silently omitted |
| Measurement equipment identification | The gauge used is identified and calibrated | Gauge column left blank or reading “inspection” |
| Nonconformance documentation, if any | Deviations are declared and dispositioned, not hidden | Field 19 marked “no” while Form 3 shows an out-of-tolerance result |
| Certificate of conformity | The shipped lot corresponds to the approved first article | Certificate references a different revision to the FAI |
MW+ ships a certificate of conformity, a CMM inspection report and material certificates with every order. FAI to AS9102 and PPAP Level 3 are quoted per programme, because they carry real engineering hours. The same logic runs through our approach to CNC machining quality control.
Worked example: does the gauge on Form 3 prove the tolerance?
Form 3 names the equipment used for each characteristic, and the buyer’s job is to ask whether it can resolve what it claims to have proved. The conventional rule is 10:1 — the measurement system should discriminate to roughly a tenth of the tolerance band.
Take a bore specified as Ø12.000 mm ±0.01 mm.
- Tolerance band = upper limit minus lower limit = 12.010 − 11.990 = 0.020 mm
- 10:1 rule: required discrimination = 0.020 ÷ 10 = 0.002 mm
- A digital caliper resolving to 0.01 mm gives a ratio of 0.020 ÷ 0.01 = 2:1 — five times worse than the rule, and the instrument’s own uncertainty is larger than its resolution
- A bore gauge resolving to 0.001 mm gives 0.020 ÷ 0.001 = 20:1 — comfortably inside the rule
A Form 3 row reporting “11.997 mm, pass” against a gauge listed as “caliper” has not proved conformance; it has produced a number. It is the most useful check a non-metrologist can run, and it takes seconds per row.
What to do when a result sits near a limit — guard banding, and subtracting uncertainty from the conformance zone — is set by ISO 14253-1; we cover marginal results in the guide to CMM inspection reports. For uncertainty vocabulary, see NIST Technical Note 1297.
How do you accept or reject an FAI package?
Acceptance has consequences: signing releases the lot and, in most contracts, moves the argument about conformance to you. A structured pass through the file takes under an hour.
The four checks that catch most problems
- Count the balloons. Compare the number of characteristics on the ballooned drawing with the number of rows on Form 3. They must match. If the drawing has 84 characteristics and Form 3 has 78 rows, six characteristics were not verified.
- Check the revision chain. The drawing revision on Form 1, the revision on the purchase order and the revision on the ballooned drawing must be the same. A revision mismatch invalidates the whole file.
- Read the gauge column. Apply the 10:1 arithmetic above to the tightest three or four characteristics.
- Read field 19 against Form 3. If any Form 3 row shows a result outside its limits, field 19 must declare a nonconformance and a disposition must be attached.
What a rejection should say
A useful rejection names the characteristic, the form and the field. “Form 3 rows 41–46 missing against balloons 41–46 on drawing rev D” gives the supplier something to act on; “FAI incomplete” starts a week of email.
FAI, PPAP, in-process inspection or a CMM report: which do you need?
These four are routinely conflated in RFQs, and asking for the wrong one costs money without buying assurance.
| Document | Question it answers | When it applies | Typical scope |
|---|---|---|---|
| First article inspection to AS9102 | Does this process, as configured, produce a conforming part? | Before release of a new or changed part | Every characteristic, once, with full traceability |
| PPAP Level 3 | Is this process capable and controlled for series supply? | Automotive release under IATF 16949 | FAI plus control plan, PFMEA, MSA and capability study |
| In-process inspection | Is the process still where it was when we approved it? | Continuously, during the run | Key characteristics, sampled |
| CMM inspection report | What did this part actually measure? | Per lot, or on request | Controlled features on the parts inspected |
The relationship is sequential, not competitive: the FAI qualifies the process, in-process inspection keeps it there, the CMM report is the per-lot evidence. Being offered one in place of another is a conversation to have before the order. Our overview of CNC machining capabilities sets out which MW+ runs as standard and which are quoted.
Which sectors treat FAI as contractual rather than optional?
| Sector | Governing requirement | What it means for the FAI |
|---|---|---|
| Aerospace and defence | AS9102 under AS9100D | Full AS9102 form set, flowed down the supply chain, before production release |
| Medical devices | FDA QMSR, in force 2 February 2026, which incorporates ISO 13485:2016 into 21 CFR Part 820 | Process validation evidence; FAI is the practical first step in the validation file |
| Automotive | IATF 16949 with PPAP | PPAP submission, of which the dimensional results are one element |
| Energy and process | Client specification, often with third-party witness | Material traceability to heat number, plus witnessed testing where called |
| Special processes across sectors | NADCAP accreditation | Heat treat, NDT and coatings performed only by accredited sources, referenced on Form 2 |
One currency note: the FDA’s Quality Management System Regulation replaced the old Quality System Regulation content of 21 CFR Part 820 on 2 February 2026, incorporating ISO 13485:2016 by reference. Supplier agreements still citing the pre-2026 clause structure are out of date. MW+ operates to ISO 9001:2015, AS9100D, ISO 13485, IATF 16949 and NADCAP.
When is a full FAI the wrong thing to ask for?
Requiring AS9102 on everything is a common overcorrection, expensive in engineering hours that buy no assurance. The honest counter-case:
- Repeat orders with no change. If drawing, source, process, tooling and program are unchanged and production has not lapsed, a new full FAI re-proves what is already proved. Ask for the CMM report instead.
- Early-stage prototypes. On a part due for two redesigns before freeze, a full AS9102 file documents a geometry you are about to discard. A dimensional report is the right instrument until the design is stable — see our guide to low-volume cost and speed trade-offs.
- Commercial parts with wide tolerances. Where general tolerances to ISO 2768 govern and nothing is safety-critical, the accountability burden can exceed the value of the part.
- When you will not read it. An unread FAI is a cost with no control attached. If nobody will count the balloons, ask for a narrower deliverable and review that.
- As a substitute for a design review. FAI proves the part matches the drawing; if the drawing is wrong, a perfect FAI certifies a part that does not work. Manufacturability review belongs before the first cut — see our guide to design for manufacturability in CNC.
The opposite error is real too: skipping FAI on a part with tight geometric callouts, an ambiguous datum scheme or a special process in the routing is how a whole lot becomes scrap. The judgement is about change and consequence, not paperwork appetite.
How MW+ runs first article inspection
MW+ has machined precision parts in Shenzhen since 2015, across a 15,000 m² facility with 60+ CNC machining centres and 120+ engineering and quality professionals. Where a programme calls for FAI, it is scheduled as a release gate, not written up after delivery.
Characteristics are ballooned against the customer drawing, the first-off part is produced on production tooling and the production program, and results are recorded per characteristic on Form 3, so conformance is visible feature by feature rather than as one headline verdict. General machining is held to ±0.01 mm against ISO 2768-m, precision features to ±0.005 mm and critical features to ±0.001 mm, capability tracked to Cpk ≥1.67. Surface texture is verified against the callout, from Ra 3.2 µm as-machined through Ra 0.4 µm to Ra 0.1 µm polished.
Quotes are returned within 24 hours from STEP, IGES, DXF, DWG, SolidWorks or PDF files. Standard prototypes run 3–5 business days and volume production 10–15 business days, with 48-hour express available; an FAI gate is quoted with the programme so the schedule reflects it. Tight-tolerance work sits under CNC precision parts, the process envelope under CNC machining services.
Frequently asked questions
Is an FAI required on every order, or only on new parts?
Only where a trigger applies: a new part number, a change of design, source, process, tooling, location or NC program, an event affecting the process, or a two-year production lapse. Repeat orders of an unchanged part do not normally require one. Write the trigger list into the purchase order so the supplier raises it unprompted.
What is the difference between an FAI and a PPAP?
An FAI answers whether the process produces a conforming part, reported on the AS9102 forms. PPAP is the automotive release package under IATF 16949, of which dimensional results are one element alongside the control plan, PFMEA, measurement systems analysis and capability study. A PPAP contains FAI-type evidence; an FAI is not a PPAP.
Who is allowed to sign the FAI report?
Under Rev C the roles are separated: whoever prepared the report should not also approve it. Signatures close on Form 1; Forms 2 and 3 no longer carry signature blocks. Check that two distinct names appear and that the approver holds a quality role, not a production one.
What happens if the first article fails?
The nonconformance is declared on Form 1 field 19 and documented against the characteristic on Form 3. The supplier investigates root cause, corrects the process and re-runs the affected characteristics as a partial FAI. What matters contractually is that the failed report is not quietly replaced — the record of failure and correction is part of the file, and an auditor will look for it.
How many characteristics should be on the report?
As many as the drawing has. Every dimension, note, tolerance, surface finish callout, material specification and process requirement is a characteristic and gets a balloon and a row. If the drawing carries 84 and the report carries 78, ask which six were judged not to be characteristics and why.
Can an FAI be done on parts made overseas and still satisfy an audit?
Yes, if the form set is complete, material and special-process certificates trace to identifiable sources, and the supplier’s quality system is certified to a standard the auditor accepts. Location is not the variable an auditor tests; traceability is. Ask for a redacted sample package before a first order.
Does an FAI cover surface finish and material, or only dimensions?
All of them. Material and special processes sit on Form 2; dimensional and other characteristics, including surface texture callouts, sit on Form 3. A finish requirement verified by eye rather than a traced measurement is worth challenging, particularly where the drawing references ISO 21920-2, which supersedes ISO 4287.
How long should an FAI take, and how do I plan around it?
Treat it as a gate rather than a lead-time add-on: the first-off part has to be produced, measured and documented, and you have to review it, before the lot releases. Agree the review turnaround with your own quality team when you place the order — supplier delay is rarely the binding constraint. To price an FAI scope against your drawing, request a CNC machining quote.
