AML STC expansion
Finding and action-item register review for an AML STC expansion
This review examines the finding and action-item register a supplier carries into an approved model list expansion and confirms each entry is genuinely closed rather than closed in status only. A certification specialist reads the register before the package goes to the authority, tracing every finding to its owner, its evidence, and the certification basis it answers. The check separates findings that carry closure evidence from those marked resolved with nothing behind them. You get a gap assessment, a finding-to-evidence map, and a closure sequence that lets the expansion move without reopening settled items.
When this review is needed
- New models are being added to an existing STC and the register carries findings inherited from the original approval.
- A finding was marked closed months ago and no one has confirmed the closure evidence is still in the package.
- The authority has asked how each open item will be resolved before the expansion is accepted for review.
- Two engineers have handed the register back and forth and ownership of several items is now unclear.
The problem
A register accumulates findings across the life of the original STC, and each added model reopens the question of which of those findings still apply and which carry evidence. Items get marked closed to clear a status column while the substantiation that would defend the closure never makes it into the package. By the time the expansion reaches formal review, no one can say with confidence that a green register is actually a defensible one.
What gets reviewed
- Every open and closed finding on the register read against the certification basis it is meant to answer
- Ownership confirmed for each action item so no finding sits without a responsible engineer
- The evidence linked to each closed finding checked for existence, currency, and relevance
- Findings inherited from the original STC screened for whether they still apply to the added models
- Duplicate and superseded findings identified so the register does not carry conflicting closure claims
- The closure state of each item classified as evidenced, partial, or asserted-only
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 finding marked closed points to a specific document, not to a status field or a meeting note
- The linked evidence actually addresses the finding as written rather than a related but different concern
- Findings that apply only to the original models are separated from those the expansion inherits
- No two register entries make contradictory claims about the same compliance item
- Every open finding names an owner and a defined path to closure evidence
Evidence normally required
- The current finding and action-item register with its closure status
- The certification basis and issue papers for the original STC and the expansion
- The evidence documents referenced by each closed finding
- The added-model list and any effectivity notes that scope the expansion
- Correspondence with the authority that raised or accepted findings
Common discrepancies
- A finding shown as closed whose referenced report was never added to the package
- An original-STC finding carried forward that does not apply to the models being added
- Two entries for the same concern with different owners and different closure claims
- A closure note that summarizes a fix but points to no substantiating document
What is at stake
A finding closed without evidence resurfaces as an authority question at exactly the point where the schedule has no room, and the engineer who closed it has often moved on. The supplier then rebuilds the closure argument under deadline pressure, or accepts a limitation on the added models that a clean register would have avoided.
How the work runs
Inventory the register
List every finding with its current status, owner, and referenced evidence so nothing is read from the status column alone.
Test each closure
Open the referenced document for each closed item and confirm it addresses the finding as written.
Screen inherited items
Separate findings that still apply to the added models from those the expansion does not carry.
Sequence the open work
Order the remaining items by dependency and authority sensitivity into a closure plan.
What the buyer receives
- A gap assessment listing each finding whose closure is asserted but unevidenced
- A finding-to-evidence map linking every closed item to the document that defends it
- A closure sequence ordering the open items by dependency and authority sensitivity
Who uses the output
- Certification leadership deciding whether the register is ready to submit
- The STC holder answering the authority's questions on individual findings
- Program managers tracking which action items still block the expansion
How the work fits into the transaction or program
The register review runs after the technical work on the added models is largely done but before the package is offered to the authority. It converts a status list into a defended one, and its closure sequence feeds the submission plan so the expansion enters review with no finding standing on an empty reference.
Start with a single asset
Reduce finding cycles by checking the package first.
Regulatory limits
The review reads the register and its evidence for internal consistency and traceability. It does not close findings on the authority's behalf, make any airworthiness determination, or grant, approve, or extend the STC to the added models.
What this review does not cover
- Performing the engineering that would substantiate an open finding
- Corresponding with the authority in the supplier's place
- Deciding which findings the authority will accept as closed
Specific to this review
- A register can read fully green and still be indefensible, because a status column closes faster than the evidence behind it is assembled.
- Findings inherited from the original approval are the ones most often carried forward without checking whether the added models change their applicability.
- The engineer who closed a finding is frequently gone by the expansion, so a closure that lives only in memory is a closure at risk.
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.
Federal Aviation Administration. FAA type certification process, certification basis establishment, and compliance findings.
Frequently asked questions
Our register shows every finding closed. Why review it?
A closed status confirms someone changed a field, not that the evidence is present and on point. The review opens each referenced document and checks it against the finding as written, which is where asserted closures separate from defended ones.
Does the review decide which findings the authority accepts?
No. It confirms that each closure is traceable and that the evidence answers the finding. The authority makes the acceptance decision, and the review is meant to remove the surprises that make that decision take longer.
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.