First Article Inspection (FAI): Validating Reliability of Production Processes
- Galip
- Oct 31
- 3 min read
Updated: Nov 5
What is First Article Inspection?
First Article Inspection (FAI) is a systematic validation of the first parts produced in a new or revised manufacturing process. It’s the process of taking one or a few samples from the initial production run, fully inspecting them against the technical drawing and specifications.
The goal is to confirm that the manufacturing process (machines, tools, materials, and methods) can reliably produce parts that meet all design requirements (dimensions, material, and finish meet the requirements).
FAI is typically performed by the manufacturing supplier, with the results reviewed by the customer. By catching errors early, FAI helps align supplier and buyer expectations, preventing any mistakes from repeating during the production of larger volumes
Why FAI Matters?
FAI answers critical questions for both sides:
For engineers and buyers, “Can this process deliver what we designed?”
For manufacturers, “Can our process reliably produce conforming parts?”
Done right, it:
Prevents costly defects: By inspecting pre-production samples, we catch errors before the full run. This saves time and money, and it prevents material waste by reducing the chance of remakes and rejected production batches.
Validates the process: Passing the FAI confirms that the exact tools and workflows planned for production are suitable to manufacture the design. It proves that subsequent parts will conform if the process remains unchanged.
Shortens time-to-market: A structured FAI helps identify and fix issues early, preventing delays when ramping up production.
Builds confidence: It provides both sides know what “good” looks like, documented, measured, and agreed upon. Suppliers demonstrate capability to customers, and customers gain confidence in incoming quality.
In industries like aerospace, medical, automotive, in many cases, FAI is required. But even in less regulated industries, it’s simply good engineering practice.
When Do You Need FAI?
At Rototip, we recommend FAI whenever:
A new part goes into production.
A drawing revision changes a critical feature.
The manufacturing process needs to change due to new tooling, machines, materials, operators, or suppliers.
Batch sizes exceed 50 parts (number can change depending on many factors such as the design, end use, part’s cost)
A long production gap requires re-validation.
A customer requests it as part of their quality requirements.
Sometimes, only a partial FAI is necessary, for example, when only a coating or surface treatment has been changed.
What Happens During an FAI?
During FAI, each critical feature of the part is meticulously measured and tested to ensure the part is as intended
Dimensional inspection: Measure all specified dimensions and geometric features. Record actual values for numeric specs and Pass/Fail for attribute specs
Material verification: Check that the part’s material matches the spec. This may involve reviewing material test reports or performing quick checks.
Visual and surface checks: Inspect for defects (scratches, cracks, weld quality, etc.) and verify finishes or markings (labels, part numbers). Confirm that the part’s appearance meets requirements.
Functional testing: If the design specifies it, perform any operational tests to validate performance.
Together, the FAI report provides evidence that the first part meets all specified criteria. It becomes the baseline for future production runs.
While the FAI principles are universal, it is how they’re executed that makes the real difference.
How Rototip Approaches FAI
We treat FAI as a structured quality milestone. Here’s how:
Identify key characteristics: We balloon the drawing so every feature is traceable. We then get agreement from all stakeholders, including the designer, buyer, and inspector, on the features to be validated.
Manufacture first samples: We manufacture samples using the same process intended for production.
Perform inspections/tests: Our QC team performs a full inspection of the sample parts, covering dimensional checks, material verification, and a thorough surface/visual inspection.
Document and review: We compile the results into the formal First Article Inspection Report (FAIR), creating a clear record of all measurements and findings.
Communicate the results: We walk you through the report. If the part passes, we get your approval to start full production.
Analyze and adjust (if needed): If any feature is non-conforming, we don't just "repeat" the process. We work with the manufacturing partner to find the root cause, adjust the process, and produce a new sample for verification.
At Rototip, we perform FAI as a standard process for all manufacturing technologies, ensuring every new production run for our customers starts right.
Conclusion: FAI as a Partnership
A First Article Inspection (FAI) provides both parties with peace of mind, ensuring that the design intent is met and that the manufacturing process is ready for consistent production.
At Rototip, we treat FAI as more than a quality checkbox. It's a critical alignment tool that ensures expectations are met, processes are validated, and your parts arrive ready to perform.
