Skip to content

Sensor STC installation

Sensor system STC installation certification support

This review prepares the compliance evidence a sensor system needs before an installation STC can be approved for a specific airframe. A certification specialist reads the qualification data, calibration records, and installation drawings against the certification basis for the modification, then flags where a required finding has no substantiating document behind it. It is run once a supplier or modifier commits to a target aircraft and needs to know the true state of the data package. You receive a gap list keyed to each compliance finding, a trace map from requirement to evidence, and a closure sequence ordered so the applicant can work the shortfalls without stalling the STC.

When this review is needed

  • A sensor already qualified at the box level is being installed under an STC and the installed-configuration effects have not been substantiated.
  • The applicant has DO-160G test reports but no clean trace from each report to the compliance finding it is meant to close.
  • An authority pre-application meeting is scheduled and the applicant needs to state honestly what the data package does and does not yet cover.
  • The sensor was designed to one certification basis and the target airframe carries later special conditions that shift the required findings.

The problem

A sensor can pass every environmental test on the bench and still lack the evidence an installation approval turns on. The applicant holds a stack of qualification reports, a set of installation drawings, and a compliance matrix that was written before the reports came back, and no one has walked the three together to confirm they agree. The result is a package that looks complete until the authority asks which document closes a particular finding.

What gets reviewed

  • Requirement-to-evidence trace across the sensor's compliance findings for the installed configuration
  • Calibration and accuracy substantiation as installed rather than as tested on the bench
  • DO-160G environmental coverage mapped to the mounting location and its real vibration and thermal environment
  • Installation effects on the sensor and on adjacent systems sharing the same structure or bus
  • Alignment of the sensor's original certification basis with the target airframe's basis and any special conditions
  • Configuration control linking the reviewed evidence to a defined part and drawing standard

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 compliance finding names a specific report, drawing, or analysis, and that document actually supports the stated conclusion
  • DO-160G test levels match or exceed the environment at the sensor's installed location, not a generic category
  • Calibration evidence reflects the sensor's range and accuracy in the installed orientation and cabling
  • Installation drawings and the qualification test article describe the same hardware standard
  • Interface and bus loading claims trace to a document rather than an assumption carried from a prior program

Evidence normally required

  • The proposed certification basis for the modification and any special conditions on the target airframe
  • DO-160G qualification test plans and reports for the sensor
  • Calibration and accuracy substantiation data
  • Installation drawings, wiring, and mounting details for the target configuration
  • The current compliance matrix and any prior approvals the sensor has already earned

Common discrepancies

  • DO-160G reports run to a category that does not match the installed vibration or temperature environment
  • Compliance-matrix findings that cite a document which addresses a different requirement
  • Calibration data valid on the bench but never re-substantiated for the installed cable length and routing
  • Installation effects on a neighboring antenna or line replaceable unit never assessed

What is at stake

Filing an STC on an evidence package that has not been traced end to end usually surfaces the holes late, during authority review, when each open finding stalls the whole approval rather than one line of it. Rework at that stage is expensive because installation drawings, load analyses, and test plans have to be reopened after the program has already committed to a schedule.

How the work runs

01

Confirm the basis

Pin the certification basis and special conditions for the modification on the target airframe before touching the data.

02

Trace each finding

Walk every compliance finding back to the report, drawing, or analysis that is supposed to close it and mark the ones that do not.

03

Test the environmental fit

Check DO-160G coverage and calibration against the sensor's real installed location, not the bench.

04

Sequence the closure

Order the remaining tests and analyses so dependent findings unblock in the right order.

What the buyer receives

  • An evidence gap list keyed to each open compliance finding, ranked by effect on the STC schedule
  • A trace map running from each installation requirement to the document that closes it
  • A closure sequence that orders the outstanding work so dependent findings are not blocked

Who uses the output

  • Certification engineers building the STC compliance package for submission
  • Program managers deciding whether the data supports a filing date
  • Supplier engineering leads scoping the tests and analyses still owed

How the work fits into the transaction or program

The review sits between box-level qualification and the STC filing. It takes the sensor's existing test and calibration data, checks it against what an installation approval actually requires on the target airframe, and hands the applicant a defined list of work so the compliance package that reaches the authority is one they can defend line by line.

Start with a single asset

Confirm requirements map to substantiating evidence.

Jurisdiction-specific considerations

An FAA STC and an EASA STC for the same sensor installation can draw on the same qualification data but structure their required findings differently, and a validation between the two authorities can reopen findings the first accepted. The review notes where a finding is basis-specific so the applicant can plan for both paths from the same evidence set.

Regulatory limits

This work assesses whether the evidence supports the compliance findings an STC will rely on. It does not issue an airworthiness determination, grant or hold any approval, and it does not replace the authority's own review of the application.

What this review does not cover

  • Running or witnessing the DO-160G environmental tests themselves
  • Producing the installation drawings or structural substantiation
  • Acting as the applicant or the design approval holder before the authority

Specific to this review

  • A sensor's installed accuracy can degrade against its bench calibration because cable capacitance and routing change with the airframe, so bench data alone rarely closes the accuracy finding.
  • DO-160G categories are chosen for a location, so a report at the wrong category is not a paperwork issue but a genuine coverage gap the sensor may not survive.
  • Installation effects run both ways: the airframe changes the sensor's environment, and the sensor can change a neighbor's, so a single-direction analysis leaves half the finding open.
  • Special conditions on a modern airframe can add findings the sensor's original TSO or qualification never contemplated, which is why the basis comparison comes first.

Sources

Frequently asked questions

The sensor is already TSO-authorized. Why is more evidence needed for the STC?

A TSO authorization covers the article to its minimum performance standard. An installation STC has to show the sensor performs and is safe as installed on a specific airframe, which raises questions about mounting environment, calibration under real cabling, and effects on adjacent systems that the TSO never addressed. The review isolates exactly which of those installation findings the existing data already supports and which still need work.

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.