AML STC expansion
Instructions for Continued Airworthiness support for an AML STC expansion
This work reviews the Instructions for Continued Airworthiness supporting an approved model list expansion, confirming the ICA cover the added aircraft and match the approved configuration. It serves avionics and equipment suppliers extending an STC to new models, before submission. The review checks maintenance tasks, airworthiness limitations, parts data, and configuration coverage so the ICA describe the installation as approved rather than lagging behind it. You receive a gap assessment, a configuration-to-ICA coverage map, and a closure plan for the instructions that need to catch up.
When this review is needed
- The expansion adds aircraft the existing ICA never named, so their coverage has to be confirmed or created.
- The installation differs on the added models, changing maintenance tasks, access, or parts.
- An airworthiness limitation from the safety assessment has to be reflected in the ICA for the new effectivity.
- A reviewer will check the ICA against the approved configuration and the supplier wants that check done first.
The problem
The ICA are often the last document to catch up to an expansion. The certification effort focuses on showing compliance, and the continued-airworthiness instructions get treated as an afterthought that inherits the launch model's tasks. But the added aircraft can mount the equipment differently, with different access, different consumables, or a different inspection interval, and an airworthiness limitation set by the safety assessment has to appear here or it is not enforceable in service. The ICA end up describing the aircraft the STC started on, not the ones it now covers.
What gets reviewed
- ICA effectivity checked against the full list of added aircraft models
- Maintenance tasks reviewed for the installation differences on the new airframes
- Airworthiness limitations from the safety assessment reflected in the ICA
- Data for parts and consumables confirmed for the added installations
- Access, inspection, and interval instructions matched to the approved configuration
- Coverage gaps assembled into a closure plan for the STC holder
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
- The ICA effectivity names every aircraft model the expansion adds
- Maintenance tasks reflect the installation as approved on each added model
- Every airworthiness limitation from the safety assessment appears in the ICA
- Parts and consumables data match the configuration for the added installations
- Inspection intervals and access instructions agree with the approved configuration
Evidence normally required
- The existing ICA from the original AML STC
- The approved configuration and installation data for the added models
- The airworthiness limitations and safety-driven maintenance tasks
- Parts, consumables, and access data for the new installations
- The effectivity list for the expanded approved model list
Common discrepancies
- ICA effectivity that omits one or more of the added aircraft models
- A maintenance task written for the launch installation that does not fit the new access or mounting
- An airworthiness limitation from the safety assessment that never made it into the ICA
- Parts or consumables data that does not match the configuration on an added model
What is at stake
ICA that lag the approved configuration leave the operator maintaining the added installation against instructions written for a different one, which is both a compliance gap at approval and a safety exposure in service. An airworthiness limitation that never reaches the ICA cannot be enforced, so a mandatory task can silently go unperformed. A reviewer checking ICA coverage against the effectivity finds the gap, and closing it late holds up the whole expansion.
How the work runs
Check effectivity
Confirm the ICA name every aircraft model the expansion adds to the approved model list.
Match tasks to installation
Review maintenance tasks against the access, parts, and intervals of the added installations.
Confirm the limitations
Verify every airworthiness limitation from the safety assessment appears in the ICA.
Plan the updates
Sequence the coverage gaps into a closure plan before submission.
What the buyer receives
Who uses the output
- STC holders confirming the ICA cover every added model as approved
- Certification leadership ensuring airworthiness limitations are enforceable in service
- Program managers scoping the ICA updates the expansion requires
How the work fits into the transaction or program
The ICA close the loop between certification and service. They carry the airworthiness limitations the safety assessment set and describe how the approved configuration is maintained, so this review runs after the safety assessment and the configuration are fixed, and it is one of the last checks before the expansion is submitted.
Start with a single asset
Reduce finding cycles by checking the package first.
Jurisdiction-specific considerations
FAA and EASA both require ICA and both scrutinize the airworthiness limitations section, but the format and the way limitations are called out can differ between the systems. The review notes where the ICA structure or limitation wording may need adjustment so the instructions are accepted on either register.
Regulatory limits
This work reviews the ICA for coverage and consistency with the approved configuration. It does not author the maintenance program, approve the ICA, or make a compliance finding on the instructions.
What this review does not cover
- Authoring the operator's maintenance program from the ICA
- Approving the ICA or the airworthiness limitations section
- Any airworthiness determination on the added installations
Specific to this review
- The ICA are usually the last document to catch up to an expansion, so they most often still describe the launch aircraft rather than the added ones.
- An airworthiness limitation that never reaches the ICA is unenforceable in service, which turns a documentation gap into a missed mandatory task.
- Installation differences on the added models, access, consumables, or intervals, are where the inherited tasks quietly stop fitting.
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.
Frequently asked questions
Can the existing ICA just carry over to the new models?
Only where the installation is identical. The added aircraft often mount the equipment with different access, consumables, or inspection intervals, and any airworthiness limitation from the safety assessment has to be present for the new effectivity or it is unenforceable. The review confirms coverage model by model rather than assuming the launch ICA suffice.
Relevant glossary terms
Related pages
Where this fits
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