TSO finding closure
Closing requirements that have no means of compliance in a TSO program
This is support for equipment suppliers whose compliance matrix has requirements with no declared means of compliance and no one owning the evidence. A specialist reads each open requirement, selects an acceptable means of compliance for it, names the evidence source that will satisfy it, and assigns a closure owner, so the matrix carries a plan for every requirement rather than only for the easy ones. The work is done during the program, before the matrix reaches a reviewer who will ask how each requirement is shown. You receive a closure brief listing every requirement without a means of compliance, an evidence request list for what each one needs, and a disposition package showing a MOC, a source, and an owner against every requirement.
When this review is needed
- The compliance matrix has requirements with the means-of-compliance column blank or set to a placeholder.
- A reviewer asks how a specific requirement is shown, and the supplier has no declared method.
- Several requirements were expected to be covered by a report that was never commissioned.
- A requirement has evidence attached but no stated method connecting the evidence to the requirement.
The problem
A means of compliance is the declared method by which a requirement is shown: test, analysis, inspection, or a combination. When a requirement has no means of compliance, it also tends to have no owner, because the two go together, and the requirement sits in the matrix looking tracked while nobody is actually responsible for showing it. These are the requirements that get skipped in planning because they were hard to method, and they surface late, when the article is built and there is little room to add the test or analysis they turn out to need.
What gets reviewed
- Every requirement in the matrix with no declared means of compliance identified
- An acceptable means of compliance selected for each, matched to the requirement and the article class
- The evidence source named for each method, whether an existing report or work to be commissioned
- A closure owner assigned to every open requirement so responsibility is explicit
- Requirements with evidence but no stated method connected to a declared means of compliance
- A reconciled matrix showing a method, a source, and an owner against every requirement
What gets validated
- Every requirement carries a declared means of compliance appropriate to what it demands
- Each selected method has a named evidence source, existing or planned, rather than a placeholder
- Requirements with attached evidence state the method that ties the evidence to the requirement
- Every open requirement has a single accountable closure owner, not a shared blank
- No requirement is closed by a method the article class does not support for that requirement
Evidence normally required
- The compliance matrix in its current state, including blank and placeholder cells
- The certification basis and the requirements it sets
- Existing reports, analyses, and test results that could serve as evidence sources
- The article definition needed to judge which methods are feasible
- Any reviewer comments asking how a requirement is shown
Common discrepancies
- A cluster of requirements expected to be covered by a report that was never commissioned
- A requirement with evidence attached but no method stated to connect it
- A hard-to-method requirement skipped in planning and never picked back up
- A placeholder means of compliance left in the matrix and never resolved to a real method
What is at stake
A requirement with no means of compliance is unshown, and a reviewer will not accept a requirement that has no declared method behind it. Closing it late is the expensive case, because selecting a means of compliance can commit the program to a test or analysis that needs the article, a lab, or an analyst who is already fully booked. A matrix that reaches review with blank methods signals that the compliance plan was never finished, which invites the reviewer to probe the requirements that do have methods too.
Move from findings to resolution
Identify the missing data behind the finding.
How the work runs
Find the unmethoded
Identify every requirement in the matrix with no declared means of compliance or only a placeholder.
Select the method
Choose an acceptable means of compliance for each, matched to the requirement and the article class.
Name source and owner
Assign an evidence source and a single closure owner to each open requirement.
Reconcile the matrix
Deliver a matrix with a method, source, and owner on every requirement, plus a disposition package.
What the buyer receives
- A closure brief listing every requirement without a means of compliance
- An evidence request list naming the report, analysis, or test each requirement now needs
- A disposition package showing a means of compliance, a source, and an owner against every requirement
Who uses the output
- Certification leadership choosing methods that fit the program's remaining schedule
- Engineering leads who now know which tests and analyses to commission
- Program management tracking method assignment to completion across the matrix
How the work fits into the transaction or program
This finishes the compliance planning the matrix started, sitting between the certification plan and the evidence campaign. It converts blank and placeholder cells into declared methods with owners, so the campaign the supplier runs covers every requirement and the reviewer sees a plan rather than a gap.
Start with a single asset
Confirm each requirement maps to substantiating evidence.
Jurisdiction-specific considerations
FAA and EASA both expect each requirement to be shown by a declared, acceptable means of compliance, and both will treat a blank method as an open item. The available means of compliance can differ slightly by authority and article, so a method acceptable to one may need adjustment for the other, and the selection is made per authority.
Regulatory limits
The work selects and assigns means of compliance and names owners and sources. It does not execute the methods, does not determine airworthiness, and does not accept a means of compliance on behalf of an authority; the authority decides whether the declared method is acceptable.
What this review does not cover
- Running the tests, analyses, or inspections that the assigned methods require
- Setting the certification basis or the requirements themselves
- Design changes to make a requirement satisfiable by an easier method
Specific to this review
- A requirement with no means of compliance usually has no owner too, because method and ownership are assigned together or not at all.
- The requirements left without a method are the ones that were hard to method, so closing them tends to commit real test or analysis, not paperwork.
- Evidence with no stated method is a hidden gap: the report exists but nothing declares how it shows the requirement, so a reviewer treats the requirement as unshown.
- Placeholder methods are worse than blanks, because they read as planned in a glance and only fail on a close read.
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. FAA type certification process, certification basis establishment, and compliance findings.
SAE International. Development assurance process at aircraft and system level, including requirements capture and validation.
Frequently asked questions
Some requirements already have evidence attached. Why do you say the means of compliance is missing?
Evidence and a means of compliance are not the same thing. A means of compliance is the declared method, such as test or analysis, that says how the evidence shows the requirement. A requirement can have a report attached with no statement of the method connecting them, and a reviewer will treat that requirement as unshown until the method is declared and the evidence is tied to it.
Relevant glossary terms
Related pages
Where this fits
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