STC conformity evidence
STC program conformity records evidence support
This review confirms that the conformity records behind an STC tie every test article and installation to a controlled configuration, so the test evidence can be credited. A certification engineer runs it before submittal, once the conformity inspections and their records exist. It reads the article identity, the as-tested configuration, and the eligibility of each test, then checks that what was tested matches what the compliance data claims. You get a gap assessment, a trace map from test evidence to the conformed article, and a closure plan for the records that do not establish eligibility.
When this review is needed
- Environmental or functional testing is complete and the conformity records have to establish the test articles were eligible.
- A test article was modified between conformity and test and the records have to show the as-tested state.
- The installation on the test aircraft has to be tied to the configuration the compliance data claims.
- A supplier ran qualification testing and the modifier needs the conformity of those articles confirmed for the STC.
The problem
Test evidence is only worth the conformity behind it. A DO-160G environmental result or a functional test proves compliance only if the article that was tested is the article the design defines, in the configuration the compliance data claims. When conformity inspections, test setups, and article changes are recorded separately, it is easy to end up with a strong test result on an article whose eligibility no one can actually reconstruct, and that result cannot be credited.
What gets reviewed
- Article identity tied to the design definition for each test
- As-tested configuration against the configuration the compliance data claims
- Inspection records covering the conformity of the articles and installations tested
- Test eligibility established before each conformity-dependent test
- Changes to test articles between conformity and test, and their disposition
- Installation conformity on the test aircraft where the STC uses in-service testing
Scope this review
Tell us the asset, the event, and the evidence in scope, and we will outline a focused first engagement.
Identify what is missing against the means of compliance.
What gets validated
- Each credited test traces to a conformed article at the configuration the data claims
- Article changes between conformity and test are captured and re-conformed where required
- Conformity inspection records identify the article by part and serial number
- The as-tested configuration matches the baseline the compliance evidence references
- Supplier qualification articles carry conformity the modifier can credit on the STC
Evidence normally required
- Conformity inspection records for the test articles and installations
- The design definition and configuration the articles were built to
- Test setup and as-tested configuration records
- Change records for articles modified during the test program
- The certification basis and the test plans requiring conformity
Common discrepancies
- A credited test on an article whose conformity cannot be reconstructed
- An article modified after conformity without re-established eligibility
- As-tested configuration that does not match the compliance data's claimed baseline
- Supplier qualification results without conformity the modifier can credit
What is at stake
A test whose article was not conformed, or was modified after conformity without re-establishing eligibility, cannot support a compliance finding, and the fix is usually a retest. Discovering that at formal review means the schedule absorbs both the finding and a return to the test facility. On qualification testing run by a supplier, an eligibility gap can strand results the whole STC was counting on.
How the work runs
Identify the articles
Tie each test article to its part and serial identity and the design definition it was built to.
Confirm as-tested state
Check the as-tested configuration against the baseline the compliance data claims.
Establish eligibility
Confirm conformity was established before each credited test and after any article change.
Close the eligibility gaps
Plan the re-conformity or retest for articles whose eligibility does not hold.
What the buyer receives
- A gap assessment on conformity across the test articles and installations
- A trace map from each credited test to the conformed article and configuration
- A closure plan for the records that do not establish test eligibility
Who uses the output
- Certification engineers confirming test results are eligible for compliance credit
- Quality and conformity staff reconciling as-tested state to the inspection records
- Program managers deciding whether a retest is needed before submittal
How the work fits into the transaction or program
Conformity is the bridge between the physical test program and the compliance data package. This review confirms the bridge holds before the results are cited for credit, so a test the program spent time and money on is not stranded by an eligibility gap the authority would catch at formal review.
Start with a single asset
Reduce finding cycles by checking the package first.
Jurisdiction-specific considerations
FAA and EASA both require conformity behind credited test evidence, and where the STC is validated across both, the review notes where the conformity trail has to satisfy a second authority reviewing whether the tested article represents the type design.
Regulatory limits
The review confirms the conformity records establish test eligibility against the configuration. It does not perform conformity inspections, witness or approve tests, sign a compliance finding, or make an airworthiness determination.
What this review does not cover
- Performing conformity inspections or witnessing tests
- Re-running any test whose eligibility is in question
- Signing a compliance finding on the tested article or granting the STC
Specific to this review
- A strong test result carries no compliance credit if the article it was taken on was not conformed to the design at the configuration the data claims.
- An article modified after conformity but before test is a frequent eligibility break, because the change disturbs the very configuration the conformity established.
- Supplier qualification results can be stranded on the STC if the modifier cannot credit the conformity of the articles the supplier tested.
Sources
U.S. Government (eCFR). Type certificates, STCs (Subpart E), TSO authorizations (Subpart O), PMA (Subpart K), and export airworthiness approvals (Subpart L).
Federal Aviation Administration. STC application process, certification basis, and continued airworthiness obligations of an STC holder.
European Union / EASA. EASA design and production certification, STCs, ETSO authorizations, and EASA Form 1 release.
RTCA. Environmental qualification test categories and procedures referenced by TSO and equipment qualification.
Federal Aviation Administration. FAA type certification process, certification basis establishment, and compliance findings.
Frequently asked questions
The test passed. Why does conformity change whether we can use it?
A passing result only supports compliance if the article tested is the article the design defines, in the claimed configuration. If conformity cannot tie the tested article to that baseline, an authority cannot credit the result, no matter how the test went, and the usual remedy is to re-establish eligibility or retest.
Relevant glossary terms
Related pages
Where this fits
Talk to an engineer who has done this work
We will walk through your current state, the records or evidence involved, and a scoped first engagement.
Talk through the aircraft, records, evidence, deadline, and next useful step.