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Learning with Leo: Why Risk-based Auditing Is Reshaping Cable Assembly Quality

Effective product development requires early and active participation from all stakeholders. The design process must include input from supply chain, manufacturing engineering, purchasing, quality, and production. A design cannot be considered complete until it has been evaluated against the full manufacturing process, whether executed by an OEM or a subcontractor. Without this collaboration, designs are often released that are not manufacturable in real-world conditions.

This challenge is becoming more visible across the industry. Manufacturers are increasingly encountering cable assemblies that do not fit, cannot be reliably built, or fail to meet performance expectations, resulting in costly delays and shipment disruptions. The need for a more disciplined, standards-driven approach is clear.

At the same time, customer audits are evolving. Organizations are seeing a shift away from basic quality system reviews toward risk-of-failure audits. This change reflects a broader concern: persistent quality issues that have significant downstream impact on product reliability, supply chain performance, and overall process control.

Recent summaries from the Department of Defense Inspector General¹ contract oversight reviews highlight recurring weaknesses, including inadequate surveillance plans, inconsistent use of qualified personnel, and gaps in verifying quality control procedures. The implication is that when oversight cannot demonstrate effectiveness, requirements become more stringent.

From a design perspective, this reinforces the need for detailed evaluation of cable and harness assemblies. This includes understanding material selection, tooling requirements, and application-specific constraints to ensure the product can be built correctly. From a manufacturing standpoint, expectations center on process control, particularly in termination methods such as crimping and soldering, and verification that operators are properly trained and competent.

However, recognizing these requirements is only part of the solution. Organizations must also have a structured method to verify that these elements are consistently implemented and effective in practice; a standards-based assessment becomes critical.

One of the most effective ways to address these challenges is through a formal, standards-based assessment aligned with IPC/WHMA-A-620, which enables organizations to validate both process compliance and operator competency.²

Key assessment areas include:

• Conductor preparation, terminations, and splices
• Lacing, tying, shielding, and labeling
• Strain relief and mechanical support
• Cable routing and support (including bend radius, chafing risks, clearance from moving or heat sources, and service loops)
• Crimp quality as a secondary, but critical, focus

This type of assessment places particular emphasis on cable routing, support structures, and the mechanical integrity of terminations and interconnections. It also enables organizations to identify gaps before they result in nonconformance, audit findings, or field failures.

In today’s environment, cable assemblies are no longer a purely build-to-print activity. They must be built as a fully integrated process that demands alignment between design intent, documentation, and manufacturing execution. Organizations that fail to connect these elements will continue to face avoidable risks, from production delays to product failure in the field.

IPC/WHMA-A-620 provides a proven framework, but compliance alone is not enough. Success depends on how effectively that framework is applied—through cross-functional collaboration, disciplined process control, and verification of operator competency. Standards-based assessments offer a practical way to validate these efforts, identify gaps, and strengthen overall performance.

As customer and regulatory expectations evolve, companies that take a proactive approach by investing in design-for-manufacturability, process validation, and workforce capability will be best positioned to deliver consistent quality, reduce risk, and meet the demands of an increasingly complex supply chain.

Cable assembly challenges are not new, but the level of scrutiny surrounding them is. As designs become more complex and expectations for reliability increase, the margin for error shrinks. What may appear to be minor gaps in design definition, documentation, or process control can quickly escalate into significant production and performance issues.

IPC/WHMA-A-620 remains the industry benchmark, but its effectiveness depends on consistent interpretation and disciplined application across all functions involved. This requires more than technical knowledge; it demands collaboration, accountability, and a clear understanding of how each decision impacts the final product.

The shift toward risk-based auditing only reinforces what many in the industry are already experiencing: It is no longer sufficient to demonstrate that a process exists; organizations must show that it works. That proof comes from well-defined requirements, controlled processes, and a workforce capable of executing to the standard.

In aerospace and defense, the demand for highly reliable cable and harness assemblies mirrors broader industry trends highlighted in IPC/WHMA-A-620: Designs are complex, expectations are high, and failures carry serious consequences.³ Major primes are actively recruiting quality engineers, program quality leaders, and supplier quality specialists to manage risk at the intersection of engineering, production, and the supply base. Job descriptions stress supplier oversight, surveillance, and program support. These are the very areas where government audits and enforcement of standards have intensified.

Meeting specification requirements is no longer enough. New hires must engage early and deeply in design reviews, documentation validation, and manufacturing oversight. Their involvement is essential to ensure that processes are not just defined but demonstrably effective, helping organizations reduce risk, maintain compliance, and deliver assemblies that meet stringent aerospace and defense expectations.

As the industry moves forward, those who take a proactive approach by focusing on design integrity, manufacturing readiness, and standards-based validation will be better equipped to meet both customer expectations and regulatory demands.

References

1. Summary Report: Lessons Learned from DoD OIG Reports on Contract Oversight (Report No. DODIG-2025-096), U.S. Department of Defense Office of Inspector General, May 2025.
2. IPC/WHMA A-620F-2025: Cable And Wire Harness Assemblies, ANSI Blog, Jan. 21, 2026.
3. ECSS-Q-ST-20-30C: Space product assurance, European Cooperation for Space Standardization, March 19, 2025.

Leo Lambert is the technical director at EPTAC Corporation.