Engineering and Test Evidence for Aircraft Wiring Modifications

Lectromec helps Part 25 Supplemental Type Certificate (STC) teams address the wiring changes associated with aircraft modifications. We support electrical engineering and certification teams with specialist wiring-system analysis, component testing, and compliance documentation.

Whether your program is defining its certification approach or addressing gaps in existing evidence, Lectromec can help establish a clear scope of work.

Start With the Modification

The first step is understanding what changes on the aircraft:

• What wiring or electrical components are added, replaced, or disturbed?
• How do routing, separation, protection, or installation conditions change?
• What qualification and compliance evidence is already available?
• What questions remain before the next certification milestone?

These questions help focus the engineering effort on the needs of your installation.

From Modification Scope to Supporting Evidence

Define the Evidence Needed

Lectromec reviews the proposed changes, installation conditions, and applicable certification basis with your team. We help identify the analysis, testing, and documentation needed to support the program.

Assess the Installation and Components

Our support can address wiring separation, protection, safety, component suitability, and qualification gaps. Where testing is needed, we help define the technical objectives, develop procedures, and generate supporting laboratory evidence.

Prepare the Documentation

Lectromec supports compliance documentation, test reports, responses to certification questions, and maintenance documentation, including Instructions for Continued Airworthiness (ICA) and Enhanced Zonal Analysis Procedure (EZAP) support.

FAA Designated Engineering Representative (DER) approval or recommendation is provided within the applicable delegated authority. See our EWIS certification and FAA DER support page for the authority table and broader certification services.

Know What Your Team Will Receive

Each engagement begins with an agreed scope and deliverables. Depending on the project, these may include:

• A review of existing qualification evidence and remaining gaps.
• Compliance and test matrices.
• Qualification plans and detailed test procedures.
• Component testing and test reports.
• Wiring installation assessments.
• Continued-airworthiness documentation support.

The goal is to give your team a defined work package with clear review responsibilities and useful engineering outputs.

Already Have an ODA or DER?

Lectromec can work alongside your existing engineering and certification organization.

Customers with an Organization Designation Authorization (ODA), or their own DER, can engage Lectromec for specialist analysis, testing, and documentation.

The scope, approval interfaces, conformity requirements, and witnessing responsibilities are established for each engagement.

Engineering and Laboratory Support

Lectromec combines wiring-system engineering expertise, FAA EWIS DER support, and an ISO/IEC 17025 accredited laboratory. Learn more about our wire and cable certification testing.

Applicable test methods and accreditation coverage are confirmed when the test program is scoped.

Discuss Your STC Project

Bring us the aircraft model, a brief description of the wiring changes, your current program stage, and your next certification milestone.

Lectromec can help define the engineering, testing, and documentation needed to move your modification forward.