Means-of-compliance gaps
When a certification requirement has no means of compliance assigned
This page is for avionics and airborne-equipment suppliers whose certification basis contains requirements that no means of compliance has been assigned to. The trigger is usually a matrix pass before submittal that surfaces empty MOC cells, or an authority question that exposes a requirement nobody planned to show compliance for. We review the certification basis, the means-of-compliance plan, the requirements set, and the verification record to find every requirement with no MOC or an MOC that does not actually demonstrate the requirement. You receive a coverage map of the unassigned requirements, a proposed means of compliance for each, and the evidence each one will need.
When this review is needed
- A pre-submittal pass through the matrix turns up requirements with an empty means-of-compliance cell.
- An authority question asks how a particular requirement is shown to be met and the team has no method on record.
- The certification basis was amended and the new or changed requirements were never assigned a compliance method.
- Derived requirements came out of the design and safety work but never picked up a means of compliance.
- A program changed scope and requirements migrated faster than the means-of-compliance plan tracked them.
The problem
A means-of-compliance gap is quiet. The matrix row exists, the requirement is written, and the program reads as on track until someone asks which method shows it is met. By then the requirement may need a test that was never planned, an analysis that needs data nobody collected, or a statement that depends on design detail that has since changed. The cost of a late method choice is higher than the choice itself, because the verification work it implies has to be retrofitted into a schedule that assumed it was done.
What gets reviewed
- Every requirement in the certification basis and whether a means of compliance is assigned to it
- Any requirement whose assigned method does not actually demonstrate what the requirement states
- Derived requirements from the system, software, and hardware work and their compliance methods
- The means-of-compliance plan and whether it covers the current requirements set
- How each proposed method maps to an acceptable means of compliance for that requirement
- The verification activity each unassigned requirement will need once a method is chosen
- Anything affected by a basis amendment that was never reassigned a method
What gets validated
- Each requirement in the basis has a means of compliance recorded against it
- The assigned method is capable of demonstrating the specific requirement, not a related one
- Methods relying on test point at a planned or completed test that covers the condition
- Methods relying on analysis name the analysis and the data it consumes
- A derived requirement carries a method just as a basis requirement does
- Selected methods are acceptable means of compliance for the requirement type, not informal substitutes
- Basis amendments are reflected as assigned methods for every requirement they touched
Evidence normally required
- The certification basis and the means-of-compliance plan
- The full requirements set, including derived requirements
- The current compliance matrix with its method column
- Verification artifacts and test plans assembled so far
- Any authority correspondence questioning a compliance method
Common discrepancies
- Basis requirements with an empty means-of-compliance cell carried as if planned
- A method named in the matrix that demonstrates a different requirement than the one it sits against
- A derived requirement with no compliance method because it never entered the plan
- Methods relying on a test that was never scheduled or scoped to the right condition
- Amended-basis requirements still showing the method for the superseded requirement
- Analysis-based methods that name no analysis and consume no identified data
What is at stake
Requirements without a means of compliance become open items the authority can hold the whole submission against. A method chosen late may force a test article, a flight or ground test slot, or an analysis cycle that the plan never budgeted. Each retrofitted method pushes verification, and verification pushes the date the article can be authorized and sold.
Move from findings to resolution
Identify the missing data behind the finding.
How the work runs
Inventory the requirements
Pull every requirement in the basis, including derived ones, and check each for an assigned means of compliance.
Test each assignment
Confirm the assigned method can actually demonstrate the requirement it sits against, not a related one.
Propose methods for the gaps
For each unassigned or mismatched requirement, propose an acceptable means of compliance and the verification it needs.
Scope the closure
Order the proposed methods by the verification effort they drive so the team can sequence the retrofitted work.
What the buyer receives
- A coverage map of requirements with no means of compliance or a mismatched one
- A proposed means of compliance for each unassigned requirement
- The verification activity each proposed method implies, scoped for planning
- A prioritized closure list ordered by the verification effort each method drives
Who uses the output
- Certification leads deciding which methods to commit to before submittal
- Engineering teams scoping the verification each new method requires
- Program management sequencing the retrofitted verification work
How the work fits into the transaction or program
The review sits ahead of a compliance matrix review. Finding the requirements with no method is the step before reconciling the matrix, because a matrix cannot be reconciled until every requirement has a method to reconcile against. It supports the supplier's own program; the supplier decides which methods to commit.
Start with a single asset
Confirm each requirement maps to substantiating evidence.
Regulatory limits
Endeavor Elements proposes means-of-compliance options and identifies gaps in the applicant's plan. It does not select the method on the authority's behalf, make compliance findings, or guarantee that a proposed method will be accepted. The applicant and the authority retain those roles.
What this review does not cover
- Making the compliance finding or accepting a method on the authority's behalf
- Performing the verification test or analysis the chosen method requires
- Issuing any approval or authorization
Specific to this review
- A means-of-compliance gap shows up as a quiet empty cell rather than a flagged error, which is why it survives until an authority question exposes it.
- A method chosen late costs more than the method itself, because the verification it implies has to be retrofitted into a schedule built without it.
- Derived requirements are the most common source of unassigned methods, because they originate in design and safety work after the plan was first written.
- A method can be present and still wrong: it may demonstrate a neighboring requirement rather than the one it sits against.
Sources
U.S. Government (eCFR). Type certificates, STCs (Subpart E), TSO authorizations (Subpart O), PMA (Subpart K), and export airworthiness approvals (Subpart L).
SAE International. Development assurance process at aircraft and system level, including requirements capture and validation.
RTCA. Objectives and lifecycle data for airborne software assurance, by design assurance level (DAL A-E).
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
How is this different from a compliance matrix review?
A matrix review confirms that assigned methods point at evidence that holds up. This step comes first: it finds the requirements that have no method at all, so there is something for the matrix review to reconcile.
Do you choose the means of compliance for us?
We propose acceptable options and the verification each one implies. The applicant decides which method to commit to, and the authority retains its role in accepting it.
Relevant glossary terms
Related pages
Where this fits
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