An engine may be developed in one country, installed in another and operated globally.
Consequently, certification evidence often travels between authorities.
This process is known as validation.
What Is Validation?
Validation occurs when one authority evaluates certification findings generated under another authority’s system.
Examples include:
- FAA certification validated by EASA.
- EASA certification validated by the UK CAA.
- FAA certification validated by other national authorities.
Validation supports international aircraft operations while maintaining sovereign regulatory oversight.
Why Validation Is Necessary
Although regulations are broadly similar, authorities retain independent responsibility for aviation safety.
Consequently:
- Rules may differ.
- Guidance may differ.
- Interpretation may differ.
- Special conditions may differ.
Validation ensures these differences are properly assessed.
The Challenge for Fire Testing
Fire-testing programmes often rely on:
- Guidance material.
- Means of compliance.
- Accepted standards.
Differences in interpretation can affect whether evidence generated for one authority is considered sufficient by another.
A Practical Example
The deep-dive highlights the importance of AC 21-16G.
This is FAA guidance.
While highly influential, it should not automatically be treated as an EASA position.
For EASA programmes, applicants must map evidence into the applicable CS-25, CS-E, AMC and guidance framework before assuming acceptance.
The Importance of Early Authority Engagement
One of the most effective methods of reducing validation risk is early engagement.
Key questions include:
- Which authority is primary?
- Which authorities will validate?
- What standards are proposed?
- What means of compliance are planned?
- What evidence will be reused?
These questions should be resolved before certification testing begins.
Why Traceability Matters
Validation authorities rarely focus solely on the test report.
They focus on traceability.
They want to understand:
- The requirement.
- The certification basis.
- The certification BOM.
- The test method.
- The representative conditions.
- The resulting evidence.
Strong traceability simplifies validation.
Weak traceability creates risk.
Conclusion
Validation is not a paperwork exercise.
It is a technical process that confirms certification findings remain valid within a different regulatory framework.
Successful aerospace fire-testing programmes therefore begin by identifying not only the test method, but also the authorities, certification basis and validation strategy that will ultimately govern acceptance of the resulting evidence.