AML STC expansion
DO-160G environmental qualification support for an AML STC expansion
This work reviews the DO-160G environmental qualification behind an approved model list expansion, confirming the qualified categories and test levels cover the environment of the aircraft being added. It supports avionics and equipment suppliers extending an STC to new models, before the package is submitted. The review compares the equipment's qualification envelope against the installation environment on each added airframe and finds where the two do not match. You receive a gap assessment, an environment-to-qualification map, and a closure plan for the categories that need re-test.
When this review is needed
- The equipment is qualified to categories set for the launch aircraft and the added models put it in a different zone or environment.
- A new installation location changes the vibration, temperature, or electromagnetic environment the box actually sees.
- The qualification report predates the expansion and its installation assumptions have to be re-checked against the new airframes.
- A reviewer will compare qualified categories to the installation and the supplier wants the comparison done first.
The problem
A DO-160G qualification report is written against a set of installation assumptions: a zone, a mounting, a power quality, an electromagnetic environment. Those assumptions were true for the launch aircraft. On an added model the box can sit in a different location with different vibration and temperature, and the report's qualified categories may no longer bound what the equipment experiences. The report looks complete because it is; it just may not cover the new installation.
What gets reviewed
- The equipment's qualified DO-160G categories and levels compared to each added installation environment
- Installation assumptions in the report re-checked against the new zones and mountings
- Environmental categories where the added airframe is more severe than the launch model identified
- Sections whose qualification carries over unchanged confirmed for the added effectivity
- Test-level shortfalls scoped to the specific categories that need re-test
- Open categories 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
- Each qualified category and level bounds the corresponding environment on every added aircraft model
- The installation assumptions in the report match the actual zone and mounting on the new airframes
- Vibration and temperature categories reflect the new installation location, not the launch position
- Electromagnetic and power-quality categories fit the environment of the added models
- Categories that carry over unchanged are confirmed rather than assumed
Evidence normally required
- The DO-160G qualification report and test plan for the equipment
- The installation description, zone, and mounting for each added aircraft model
- The environmental envelope defined for the added airframes
- The category selection rationale from the original qualification
- Any electromagnetic environment or power characteristics data for the new installation
Common discrepancies
- A vibration category qualified for the launch position that is too low for the added installation zone
- Installation assumptions in the report that no longer describe the new mounting
- A temperature category set by the original airframe that the added model exceeds
- An electromagnetic environment on the new airframe outside the qualified category
What is at stake
If a qualified category falls short of the added installation environment, the equipment is not shown to survive where it now flies, and that is a substantive compliance gap rather than a paperwork one. Closing it can mean re-testing to a higher category, which is schedule and cost the program did not plan for. Catching the mismatch before review is the difference between a planned test and a finding raised against the package.
How the work runs
Read the qualified envelope
Extract the DO-160G categories, levels, and installation assumptions the report was built on.
Characterize the new environment
Define the environment each added aircraft model imposes at the actual installation location.
Compare envelope to environment
Match qualified categories against the added installation and mark every shortfall.
Scope the re-test
Build a closure plan for the categories that need re-test before submission.
What the buyer receives
- A gap assessment of the qualified categories that fall short of the added environment
- An environment-to-qualification map covering each added aircraft model
- A closure plan scoping the re-test needed to cover the shortfalls
Who uses the output
- STC holders confirming the equipment is qualified for where it will now be installed
- Certification leadership deciding which categories justify a re-test
- Program managers planning re-test cost and schedule into the expansion
How the work fits into the transaction or program
The qualification review is where the compliance map's environmental requirements meet real test evidence. It runs after the means-of-compliance map fixes which environmental categories apply, and its shortfalls feed the verification trace and the safety assessment, since a category gap can ripple into a failure-condition argument.
Start with a single asset
Reduce finding cycles by checking the package first.
Jurisdiction-specific considerations
FAA and EASA both accept DO-160G, but expectations on how installation assumptions are documented and how category selection is justified can differ. The review notes where the rationale is thin enough that one authority may ask for more, so the qualification stands on either register.
Regulatory limits
This work compares qualification evidence to the installation environment. It does not perform or witness the environmental testing, accept a qualification result, or make a compliance finding on the equipment.
What this review does not cover
- Conducting the DO-160G environmental testing itself
- Defining the aircraft-level environmental envelope
- Any finding of compliance on the qualified equipment
Specific to this review
- DO-160G qualification is only as good as its installation assumptions, and those assumptions were written for the launch aircraft, not the models being added.
- Vibration and temperature categories break most often on an expansion, because a new installation zone changes exactly what the equipment experiences.
- A category shortfall is a real physical gap, not a documentation one: the box is simply not shown to survive the environment it now sees.
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.
Frequently asked questions
Do we have to re-run the whole DO-160G qualification for the new models?
Rarely the whole thing. The review isolates the environmental categories where the added installation is more severe than the launch aircraft, so re-test is scoped to those categories. Sections whose environment is unchanged carry over once confirmed, which keeps the re-test to what the expansion actually requires.
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.