Confusion reigns over first article inspection and whether it is a qualification requirement. (It isn’t.)

SAE AS9102 defines a first article inspection (FAI) as a complete, independent and documented physical and functional inspection process to verify that prescribed production methods have produced an acceptable item as specified by engineering drawings, planning, purchase order, engineering specifications, and/or other applicable design documents. The purpose of an FAI is to provide objective evidence that all engineering, design and specification requirements are correctly understood, accounted for, verified and recorded.¹

These are industry definitions of an FAI and its purpose; however, there is often confusion regarding the definition of a first article inspection and its importance to an original equipment manufacturer, which, for the purposes of this article, will be considered the customer. This misunderstanding results in lost money and time. The customer often does not understand the purpose of an FAI and flows down its purpose incorrectly. The supplier does not understand its importance and often treats a first article inspection like a “check in the box.” These concerns cause havoc in both the design and production worlds.

The confusion often initiates with the customer. Customer design centers often do not understand the definition of a first article inspection. Often, FAI is interpreted as a qualification requirement by the customer design centers. This misguided interpretation is clearly prohibited by AS9102A, but nevertheless is conveyed to their suppliers under contract. The requirement is normally flowed down in a purchase order via a Quality Note or a Statement of Work, which references an FAI instead of Qualification. What the customer design center expects is a qualification report for a new part that verifies all design characteristics have been met either with inspection, test, analysis or demonstration. This misunderstood first article inspection definition by the customer results in a document from the supplier that does not meet the customer’s intent, resulting in lost budget and schedule. It is imperative that customer design centers understand the definitions of a “First Article Inspection” and “Qualification” and use the words in accordance with their definitions. This is very important because when these requirements are flowed down to a supplier in a contract, such as a purchase order, there are legal bindings.

Figure 1. The Quality engineer should validate that all requirements, including drawing notes, have been reviewed.

In AS9102, the definition of First Production Run Parts, prototype parts, or parts built using methods different from those intended for the normal production process, stipulates that these parts shall not be considered part of the first production run.¹ However, further into AS9102 under the section identified as Parts Requirements, AS9102 states, “This Standard may be used to verify conformance of a prototype part to design requirements.”1 On the surface these two sections appear to be in conflict and, therefore, contribute to the confusion. For qualification, the subject parts should follow an approved qualification process, which often looks at many more design characteristics than the production process inspects or tests. The qualification data produced should be captured in a qualification report that captures each and every design characteristic, including any reliability data required. Qualification often includes parts that may go through destructive testing.
Once a part is qualified and the supplier is ready to go turnkey, a first article inspection shall take place as required by the customer purchase order. The data should be produced in a format that complies with AS9102.

A first article inspection is very important to ensure that the supplier’s process, which was qualified, still produces the expected output during normal production builds. It does not apply to procured vendor parts not controlled by the customer’s drawing. It is typically used when custom parts – parts built to the customer’s Technical Data Package (TDP) – are being purchased and the supplier has never previously built them, such as sheet-metal assemblies or tailored off-the-shelf parts. This inspection standard process is used to ensure the design characteristics that are flowed down will actually meet design intent during a first production run. An FAI may also be repeated in full or in part when one of the following events occurs:

• The source or location where the item is produced changes.
• A significant change in the design affects form, fit, or functions of the part.
• A significant change in the manufacturing, assembly, inspection, or test process.
• A significant change in manufacturing equipment.
• A natural or manmade occurrence that may adversely affect the manufacturing process.
• A break in the production process for some significant time.
• Significant degradation in test yields.
• Any change in manufacturing and/or test personnel on the product line and/or operational control, like a buyer, process engineer, or quality assurance engineer.
• Any change in a vendor of supplied items that may have an age factor or revision factor.

It is essential a supplier get clarity of the purpose of the first article inspection during a pre-award meeting with the customer to mitigate the latter type of issues described above. But what is also important for the supplier to understand is that this process is not just a check in the box.

Suppliers often miss the first article inspection requirement flow down by the customer’s factory or design center. These FAI parts are often key product characteristics that drive product performance. If the first piece from the lot is not correct, then most likely other parts produced from that lot will also not be correct. It is important that the supplier quality organization, prior to the release of a shipment, has a quality engineer review the first article inspection in detail to ensure items have passed, and mistakes were not made or steps skipped. The quality engineer should also validate that all the requirements called out, i.e., notes on drawings, are carefully reviewed to ensure the product meets all design requirements. If the requirement is a numerical value, then the recorded value should be in a numerical form and not attribute data such as a pass or fail or check mark. The results shall indicate how far the recorded value was from the nominal value and be in the same units as specified by the customer’s drawing. These data points could be indicators of process shift, when they deviate significantly from the expected nominal.

Suppliers should also review the first article inspection reports that they flow down to their suppliers to support the customer’s assembly FAI, such as a circuit board card assembler that receives printed wiring boards. If these bare PCBs do not meet design intent at the supplier’s level or customer’s level, then design stack-up out of tolerances could be an issue. The costs of this defect at the customer’s manufacturing facility are much more expensive at that point to repair. If the mistake is caught earlier in the process, the defect is not as costly. It cannot be stressed enough how important it is for suppliers to review carefully the data they receive, as well as what they ship to customers.

It also cannot be said enough to format presentation. If the data are bunched without any clarity and direction, it will take the customer much longer to sift through the data, and result in many more meetings with the supplier for clarification. Presentation is vital; a first article inspection report should be easily readable. The format shall be easy to understand, such as what certifications go along with each material referenced in the first article inspection report.

Delineated below are required items that make a good first article inspection:

1. Configuration control.
2. A family tree of the product that identifies which products are critical and require an FAI. When creating the family tree, the purchase order and design requirements should be used as a base to determine what is critical.
3. A flow chart of the product build, test and inspection cycles.
4. Assembly, test and quality assurance/quality control procedures.
5. Documentation identification, Certificate of Conformance, lot identification and date of build or manufacturing run so that age check and revision can be determined should a failure analysis be required.
6. Acceptance, functional test, mechanical or inspection data, as required.
7. If acceptance limits are numerical, then data should be numerical. This will permit the customer to better understand if a potential design margin or process capability issue exists.
8. Verify critical performance characteristics have been met as required (reference International Aerospace Standard 9103 for guidance).

In the first article inspection report, the top document shall be the first article inspection report that is complete, showing each dimension, test requirement and data, material requirements, certificate of conformance with lot identification, product run numbers, manufacturing date codes, part number identification, and all other requirements called out on the drawing’s purchase order. Specifications shall be checked, verified and recorded, dated and stamped and/or signed off by a supplier representative. A copy of the drawing package, purchase order and attachments, and purchase order change notices should be included in the report. The product family tree, process flow chart, master configuration control list (MCL) if it is a requirement, a list of all procured parts with parts manufacturer’s name and part number, a list of all processes performed outside a facility, a list of special test equipment, tools and fixtures, all approved acceptance procedures used and all other substantiated data shall be included. All lower-level first article inspections should be submitted if required by the customer.

Most important, the first article report should be in a format that is organized and easily readable by the customer. For example, they should be able to locate a certificate of conformance for a subassembly part in the report.

Incremental first article inspection should be done on complex product to prevent the need for a teardown during verification. If a unit is broken down and parts replaced, the unit will not conform to the data provided in the first article report. Remember, a first article inspection is a nondestructive inspection/test of one or more items from the first lot produced to verify conformance with the P.O. and design requirements from a production perspective.

The bottom line is that the customer should understand the definition of a first article inspection and its purpose. The supplier should clarify with the customer to ensure what they in fact want is a first article inspection. Once it is clearly understood that an FAI is required, the supplier should ensure the quality engineer carefully review all first article inspection reports to ensure production processes have met design intent before the document is signed off. The documented first article report should be clear and concise in a format that is easily readable for the user/customer.

References

1. SAE AS9102, Aerospace First Article Inspection Requirement, January 2004.

Karen Ebner is senior quality engineer II; Charles A. Hill is mission assurance process lead, and G. Wilkish is prime consultant at Raytheon Space & Airborne Systems (raytheon.com); karen_ebner@raytheon.com. Raytheon will present on this topic at PCB West (pcbwest.com) in September in the Silicon Valley.