Yes, you can usually reuse data from a previous FAIR when performing a delta FAI, but only under controlled conditions. A delta FAI is intended to demonstrate conformity for the changed characteristics while maintaining traceability to the original, full FAI. Reuse is permitted where the original evidence is still valid and clearly linked.
What you can typically reuse
Subject to your customer, contract, and internal procedures, you can often reuse:
- Unchanged characteristics where the design requirement (drawing, model, spec rev) has not changed.
- Unchanged manufacturing process steps (same routing, methods, tooling, NC programs, and work instructions) that are still qualified and under control.
- Previously approved measurement methods (same gages, CMM programs, fixtures, MSA status) that remain valid and calibrated.
- Document references such as certificates, material lots, or process approvals, if they are still applicable and traceable to the parts being delivered.
In practice, this often means you can carry forward much of Forms 1 and 2 from the baseline FAI and reuse some Form 3 entries for characteristics not affected by the change, provided your procedure and customer allow it.
Where you must generate new data
New inspection data is usually required for:
- All characteristics impacted by the change (drawing revision, model change, spec change, NC program change, process change, or new supplier).
- Any operation or tooling that has changed, even if the drawing requirement did not change, where the process change could reasonably affect the result.
- Characteristics previously accepted by similarity or sampling if the basis for that acceptance is no longer valid.
- Characteristics that had past nonconformances or escapes where the risk assessment or RCCA calls for renewed verification.
Even when some values are numerically identical to previous results, a delta FAI is expected to show that you verified the changed condition under the current configuration.
AS9102 and customer-specific constraints
AS9102 (especially Rev C) allows delta FAIs focused on changes, but does not guarantee that reuse of prior data will be accepted in all cases. Common constraints include:
- Customer flowdowns that require full or partial re-FAI at each drawing revision, regardless of internal risk assessment.
- Prime- or Tier-1-specific FAI procedures that restrict reuse of historical data or require fresh measurements at defined triggers (e.g., time since last build, supplier change, NC program change).
- Contractual clauses that override your internal criteria for when a delta vs full FAI is allowed.
Your ability to reuse data ultimately depends on your approved FAI procedure, the purchase order, and any customer FAI specifications. You should be prepared to justify where and why prior data was reused.
Traceability and documentation expectations
When you reuse data in a delta FAI, you should make the reuse explicit:
- Link to the baseline FAI (FAI number, date, revision, and part configuration) in your forms and QMS records.
- Clearly distinguish characteristics with new data from those that rely on previous FAI evidence (e.g., note “verified in baseline FAI #1234” where allowed by your form format or digital system).
- Maintain configuration control to show that the reused data corresponds to the same design revision and process definition as currently authorized, or that your risk assessment confirms continued validity.
- Ensure calibration and approval status of any reused measurement methods or special processes over the time period involved.
In a brownfield environment with multiple systems (MES, ERP, PLM, QMS, and tools like Net-Inspect), gaps in integration and version control are a common failure mode. If your systems do not reliably link drawings, NC programs, work instructions, and FAIs, aggressive reuse of data can create traceability and audit issues.
Operational and risk tradeoffs
Reusing prior data has clear benefits and risks:
- Benefits: less inspection time, reduced CMM and gage load, shorter lead time to restart production after a change, and lower cost of quality effort for stable characteristics.
- Risks: using obsolete requirements, missing hidden process changes, or failing to demonstrate adequate verification to a customer or auditor because the linkage between old data and the current configuration is weak.
In regulated, long-lifecycle aerospace environments, full replacement of existing FAI records and systems every time you update a design or process is rarely practical due to validation cost, downtime risk, and integration complexity. Delta FAI with selective data reuse is a common compromise, but it only works if your change control, configuration management, and digital traceability are strong.
Practical guidance
To use prior FAIR data safely in a delta FAI:
- Start with change analysis: identify exactly which characteristics and processes are affected by the change.
- Define reuse criteria: align with AS9102, customer requirements, and your internal FAI/PPAP procedures.
- Verify data validity: check drawing revision, process routing, NC program rev, gage status, and supplier approvals.
- Document your rationale: record why specific characteristics used prior data and why that is acceptable from a risk and compliance standpoint.
- Use digital tools carefully: if you rely on Net-Inspect or in-house FAI software, ensure that reused entries are correctly linked and that audit trails reflect what changed versus what carried over.
If there is any doubt about the validity of previous data, or if customer instructions are unclear, it is safer to generate new inspection results for the affected characteristics and, when necessary, to extend that to additional features.
