Navigation equipment STC
Navigation equipment certification evidence for STC installation
This support prepares the certification evidence a modifier needs to gain STC approval for installing navigation equipment on a specific aircraft. It serves suppliers and modifiers fitting a receiver, computer, or navigation source who must show the installation meets the aircraft's certification basis. The work examines antenna siting, sensor integration, interference with existing systems, and installation assumptions, then connects them to the certification basis, the means of compliance, and the aircraft's current configuration. You receive an installation-specific evidence gap list, a trace map from requirement to substantiation, and a sequence for closing the open items ahead of the STC application.
When this review is needed
- A navigation receiver or antenna is being installed under an STC and the evidence has not been anchored to the aircraft's certification basis.
- A navigation TSO article is going into a specific aircraft and the installation case still has to be built.
- Antenna siting on the airframe raises multipath or interference questions with other navigation and communication systems.
- The installation feeds a flight display or autopilot and the integration has to be substantiated for this aircraft.
The problem
Navigation installation lives or dies on siting and integration, and neither carries over from the article's TSO. An antenna that met its standard on a test range still has to see the sky cleanly from this airframe position, without multipath off structure or interference from co-located radios. A receiver feeding an autopilot has to prove the integration is safe on this aircraft. Modifiers often hold good article data and an installation case that has not addressed the airframe-specific navigation effects.
What gets reviewed
- The aircraft's certification basis for the installation identified and turned into a compliance position
- Antenna siting on the airframe evaluated for sky visibility, multipath, and pattern
- Interference with co-located navigation and communication systems reconciled with the installation
- Integration with flight displays, autopilot, or other consumers substantiated for this aircraft
- Configuration effectivity established so the installation applies to the intended serial numbers
- Article-level navigation qualification carried into the installation case where it remains valid
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 certification basis requirement for the installation maps to installation substantiation, not just article data
- Antenna siting evidence reflects the fitted location and the structure around it, not a range measurement
- Interference analysis accounts for the navigation and communication systems already on the aircraft
- Integration with downstream consumers is substantiated for the failure effects on this aircraft
- Configuration effectivity names the serial numbers and prior modifications the installation depends on
Evidence normally required
- The target aircraft's certification basis and type design data relevant to the installation
- The navigation article's TSO or qualification data being installed
- Antenna siting and multipath analysis for the fitted location
- Interference analysis covering co-located navigation and communication systems
- The aircraft's current configuration and modification status
Common discrepancies
- Antenna performance assumed from the range measurement without airframe multipath assessed
- Interference analysis that omits a navigation or communication system already installed
- Integration with an autopilot or display substantiated for the article but not for this aircraft
- Configuration effectivity that ignores a prior modification affecting the antenna location
What is at stake
An STC package that assumes the antenna and integration from the article draws findings on siting, multipath, and interference, which can require ground or flight evaluation on the aircraft to close. Discovering a multipath or interference problem after submittal, or after the antenna is cut in, is among the most disruptive ways to learn it, and it delays the approval and the installation slots the operator has booked.
How the work runs
Anchor to the aircraft basis
Identify the certification basis for the navigation installation on the target aircraft and set the compliance position.
Substantiate siting and interference
Evaluate antenna location, multipath, and interference against the systems already on this airframe.
Prove the integration
Show the integration with displays or autopilot is safe for the failure effects on this aircraft.
Sequence the closure
Order the airframe-specific gaps ahead of the STC application.
What the buyer receives
- An installation-specific evidence gap list against the aircraft's certification basis
- A trace map linking each installation requirement to its substantiation
- A closure sequence for the open items ahead of the STC application
Who uses the output
- Certification engineers building the navigation STC installation case
- Modifiers deciding what siting, interference, or integration analysis still has to be run
- Program leads sequencing closure against the installation and approval schedule
How the work fits into the transaction or program
The support sits between the navigation article's TSO and the STC application, building the installation case around siting and integration that article data does not provide. It carries valid qualification forward and identifies the airframe-specific work that remains, so the STC package reaches the authority as a mapped installation position rather than a receiver's data with an antenna attached.
Start with a single asset
Confirm requirements map to substantiating evidence.
Jurisdiction-specific considerations
An STC approved under the FAA does not automatically carry to an EASA-registered aircraft, and where the navigation installation supports a performance-based navigation credit the operational approval follows its own path in each system. The mapping notes where an installation finding accepted by one authority needs separate work for the other.
Regulatory limits
The support prepares and maps the installation evidence for a navigation STC application. It does not grant the STC, approve the installation, deliver any operational navigation credit, or make an airworthiness determination. Those decisions rest with the authority and its designees.
What this review does not cover
- Performing the antenna, interference, or flight evaluation
- Designing the installation or developing the modification data
- Issuing the STC or any installation or operational approval
Specific to this review
- A navigation antenna qualified on a test range can still perform poorly once fitted, because airframe structure creates multipath the range never showed, so siting is substantiated for the installed location.
- Interference is a two-way problem on a crowded airframe: the navigation set can be disturbed by co-located radios and can disturb them in turn, so the analysis covers both directions.
- The performance-based navigation credit an operator ultimately wants is an operational approval that sits beyond the STC, so the installation case earns the airworthiness approval without by itself delivering the operational one.
Sources
U.S. Government (eCFR). Type certificates, STCs (Subpart E), TSO authorizations (Subpart O), PMA (Subpart K), and export airworthiness approvals (Subpart L).
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
Does a navigation STC also give the operational credit, such as a performance-based navigation approval?
Not by itself. The STC provides the airworthiness approval for the installation. The operational credit an operator wants is a separate approval that builds on the installed and approved equipment. The evidence prepared here earns the installation approval and positions the aircraft for that later operational case.
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.