What it takes to build Class 3 cable harness assemblies for aerospace and defence

In aerospace and defence, cable harness assemblies are far more than simple interconnections. They carry power, signals and data through some of the most demanding operating environments imaginable, from vibration and shock to temperature extremes and long service lifecycles.

A single failed connection can ground an aircraft or take a system offline.

Assemblies must fit correctly first time, perform reliably for years, and be supported by the documentation, testing and traceability these programmes demand.

At TechPoint, we manufacture Class 2 and Class 3 cable harness assemblies, including complex interconnect harnesses, for aerospace, defence and security applications from our dedicated cable harness facility in Basingstoke. From prototype builds to long term production, quality, reliability and compliance are at the core of everything we make.

Built to the standards your programme requires

Every cable harness assembly we manufacture is built to IPC/WHMA-A-620, the recognised industry standard for cable and wire harness assemblies.

The standard sets three classes. Class 1 is intended for general commercial products where cosmetic imperfections have little impact on functionality. Class 2 covers dedicated service products where reliability is important and extended performance is expected. Class 3 is the highest classification. It is intended for products where continued performance is critical and downtime cannot be tolerated, which makes it the usual choice for aerospace, defence and security applications.

Class 3 places tighter controls on crimp quality, soldering, wire preparation and insulation damage, as well as harness routing and support, inspection and verification.

If your drawing package or specification does not clearly identify the required class, it is worth confirming before production begins. Building to the wrong standard can introduce unnecessary cost, delays or rework.

Meeting the standard requires more than documented procedures. It depends on the knowledge and skill of the people carrying out the work. Our operators are trained and certified to IPC/WHMA-A-620 and are supported by our in house Certified IPC Trainers (CITs), so standards are maintained on every build.

All manufacturing is carried out within our AS9100 quality management system, providing the process control expected throughout the aerospace and defence supply chain.

Engineering support before production starts

Successful harness builds begin long before the first wire is cut.

Our engineering team reviews every build to print package before manufacture, identifying opportunities to improve manufacturability, reduce risk and support programme delivery. Alongside build to print manufacture, we offer Design for Manufacture (DFM) reviews, prototype and pre production builds, first article support, reverse engineering, and on site measurement and data capture.

This early engagement helps avoid the issues that most often affect schedules, including unclear documentation, unsuitable component selection and assembly challenges.

Supporting legacy and obsolescent platforms

Many military and aerospace platforms remain in service for decades, often long after the original drawings and manufacturing data have disappeared.

Our reverse engineering capability allows us to recreate cable harness assemblies from existing hardware, creating a repeatable manufacturing solution while preserving form, fit and function.

As one customer explained:

"When we had a legacy harness with no usable drawings, TechPoint reverse engineered it, improved it for manufacture and delivered on time. Responsive, flexible and easy to work with."

From prototype builds to complex production harnesses

Our facility is set up for the low volume, high mix production common across the sector. Our team regularly produces assemblies ranging from simple single core cables through to complex looms containing more than 100 conductors.

Capabilities include:

• Custom cable harness assemblies

• Multi branch harnesses

• Point to point wiring

• Multicore assemblies

• Screened and shielded harnesses

• Connector and backshell integration

• Panel and cabinet wiring

• Rack and system level interconnects

Tested, verified and fully traceable

Every assembly is inspected and tested before shipment.

Depending on the requirement, that includes continuity, insulation resistance and high potential (Hipot) testing, along with dimensional verification. In process checks run throughout manufacture, so potential issues are found and resolved early, and every build finishes with a final inspection and documentation review.

Full material, process and manufacturing traceability is maintained throughout, giving customers the information they need for audits, compliance reviews and long term programme support.

A supply chain built for long programme lifecycles

Component availability does not always keep pace with programme lifecycles.

Through our AS9120 approved supply chain, we source and manage connectors, backshells and specialist interconnect components from trusted manufacturers. We also help customers manage long lead times, obsolescence and lifecycle planning, reducing programme risk and improving continuity of supply.

Responsibly supporting the future of defence manufacturing

Environmental performance matters more and more across the defence supply chain, and environmental and social value commitments are increasingly scored in defence tenders.

At TechPoint, sustainability is built into the way we operate.

Our commitments include:

• A fully electric vehicle fleet

• Rainwater harvesting at our Basingstoke facility

• 100% renewable energy across all sites

• A 50% reduction in absolute Scope 1 and Scope 2 emissions by 2030, against a 2025 baseline

• Sustainable packaging initiatives with customers and suppliers

We believe responsible manufacturing and high performance engineering should go hand in hand.

Looking for a reliable cable harness manufacturing partner?

Whether you need a prototype build, production support for a new programme or replacement harnesses for a legacy platform, TechPoint can help.

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