A certificate on file, a completed self-assessment, a clean scorecard. For many European OEMs, that is what supplier qualification for a US source looks like in practice. It is efficient. It is also blind in three places that only show up when someone stands on the shop floor.
What the standards ask for
ISO 9001:2015 clause 8.4.1 requires organisations to determine and apply criteria for the evaluation, selection, monitoring of performance and re-evaluation of external providers. Aerospace raises the bar: the IAQG’s IA9100 Key Change Summary (November 2023) restructures clause 8.4 to add „direct and sub-tier control“ and turns counterfeit-part prevention notes into requirements in 8.1.4, including training, obsolescence monitoring and traceability. None of that can be verified fully from a desk.
Blind spot 1: the sub-tier
From my own supplier audit experience: the document package describes the supplier. It rarely describes the supplier’s suppliers. Heat treatment, plating, NDT and special processes are often outsourced. On site, you can ask for the last three purchase orders to sub-tier sources and check whether your flow-down requirements appear on them.
Blind spot 2: the revision on the bench
The quality office holds the current drawing. The machine on the floor holds the one that was printed last year. Only a walk to the workstation shows which one is used.
Blind spot 3: the people behind the certificate
A certificate confirms that a system existed on the audit day. It does not show staff turnover since then. In a tight US labour market, the inspector who knew your part last year may be gone. On site, a ten-minute conversation tells you more than the training matrix.
When a desk review is enough
Low-risk, catalogue items with stable history. For anything with special processes, safety relevance or a new part number, plan a visit — or have someone local visit for you.
Three actions
1. Rank your US suppliers by risk: special processes, safety-relevant parts, new part numbers.
2. For the top tier, request sub-tier purchase orders before the audit.
3. Put one bench-level drawing check on every audit agenda.
Sources
- ISO — ISO 9001:2015 Quality management systems — Requirements, clause 8.4.1, iso.org
- IAQG — IA9100 Key Change Summary, clause view (November 2023), iaqg.org