Navigation ETSO
ETSO compliance evidence support for navigation equipment
This support maps a navigation article's evidence against its European ETSO authorization, following the sensor inputs it depends on, the database currency its function assumes, the software level it declares, and the operational performance standards it claims alignment with. Navigation authorizations hinge on the article meeting a named performance standard exactly, and this checks that the minimum operational performance evidence and the software data close against it. An ETSO-experienced engineer runs it during evidence mapping, before an application or against a finding. You get a standards map, a gap list, and a closure sequence for the article.
When this review is needed
- A navigation article is heading for an ETSO authorization and its MOPS alignment needs a read before submittal.
- An EASA finding questioned a performance claim or a sensor-input assumption and the answer must reach test data.
- A software level was revised and the affected navigation evidence has to be re-mapped to the authorization.
- A database or reference-frame assumption changed and the reused performance evidence needs re-checking.
The problem
Navigation articles are judged against a named minimum operational performance standard, and every performance claim has to align to that standard's specific tests and pass criteria. Around that sit the sensor inputs the function consumes, the database currency it presumes, and the software level that governs its integrity. When these are assembled separately, a performance claim can align to a superseded MOPS revision, a sensor-input assumption can go untested, or the software level can sit below what the navigation integrity actually needs, and the misalignment only shows when the evidence is read against the standard line by line.
What gets reviewed
- Performance claims aligned to the specific minimum operational performance standard the ETSO invokes
- Sensor-input assumptions the navigation function depends on checked against the qualification basis
- Database currency and reference-frame assumptions reconciled with the performance evidence
- Software level declared for the navigation function mapped to the DO-178C data items
- European article-authorization representation confirmed for the evidence and deviation structure
What gets validated
- Each performance claim aligns to the current MOPS revision the authorization references, not a prior one
- Sensor-input assumptions are supported by qualification or test evidence rather than assumed
- Database currency and reference-frame assumptions match what the performance testing used
- The declared software level matches the integrity the navigation function requires
- Evidence and deviations are represented in the structure the ETSO authorization expects
Evidence normally required
- The draft ETSO application or the EASA finding to be answered
- The minimum operational performance test reports and the MOPS revision they target
- Sensor-input interface and qualification evidence
- Database currency and reference-frame assumptions
- Software life-cycle data and the declared software level
Common discrepancies
- A performance claim aligned to a superseded MOPS revision rather than the current one
- A sensor-input assumption the navigation function relies on with no test evidence behind it
- A declared software level below the integrity the navigation function actually needs
- Database or reference-frame assumptions that the performance testing did not use
What is at stake
A navigation package aligned to the wrong MOPS revision, or short on the integrity its software level should provide, draws a finding that reaches into the performance testing itself, which is expensive to redo. Because navigation articles underpin approved procedures, a late correction to the performance basis can invalidate downstream operational credit the installer was counting on.
Move from findings to resolution
Identify gaps against the means of compliance.
How the work runs
Name the standard
Fix the MOPS revision the ETSO invokes and the pass criteria it sets.
Align the performance
Trace each performance claim to a test result against that revision.
Check inputs and level
Confirm sensor-input and database assumptions hold and the software level fits the integrity need.
Sequence the closures
Order the gaps by their reach into the performance basis against the timeline.
What the buyer receives
- A standards map aligning each navigation performance claim to the MOPS evidence behind it
- A gap list ranked by how far each misalignment reaches into the performance basis
- A closure sequence ordering the performance, sensor, and software work that remains
Who uses the output
- Certification engineers preparing the ETSO application for the navigation article
- Compliance managers judging which MOPS or software gaps block submittal
- Engineering leads directing the performance and software work that closes them
How the work fits into the transaction or program
The mapping runs where the performance, sensor, database, and software threads have to align to one named standard, reading them against it so a misalignment is caught before the article underpins a procedure. Its gap list drives the performance and software closures, and its standards map anchors the finding responses to the MOPS evidence.
Start with a single asset
Confirm requirements trace through verification.
Jurisdiction-specific considerations
The MOPS revision an ETSO invokes can lag or lead the revision an equivalent FAA authorization references, so a navigation article aligned for one authority may face a different target revision for the other. The mapping flags where the performance basis is anchored to a revision the second authority does not currently accept.
Regulatory limits
The mapping reads the navigation evidence and reports its alignment to the referenced standard. It does not grant an ETSO authorization, approve the article, or make an airworthiness or operational-approval determination on the navigation function.
What this review does not cover
- Running the missing performance or sensor-input tests
- Filing the ETSO application for the supplier
- Any operational approval or airworthiness determination on the navigation article
Specific to this review
- Navigation articles are judged against a named MOPS, so alignment to the exact referenced revision matters more here than on equipment measured by category alone.
- A software level set too low for the navigation integrity is a recurring finding, because the level is fixed early and the integrity need is understood late.
- Because navigation underpins approved procedures, a late change to its performance basis can strip operational credit that was already priced into the installation.
Sources
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.
RTCA. Objectives and lifecycle data for airborne software assurance, by design assurance level (DAL A-E).
Frequently asked questions
The referenced MOPS was revised while we were testing. Does our evidence still count?
It depends on which revision the ETSO authorization invokes and how the revision changed the tests or pass criteria. Evidence produced against an earlier revision may still align, or may need supplementary results. The map identifies exactly which claims are affected by the revision and which stand as tested.
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.
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