Reverse-engineering operationally critical subsea cables

Challenge

Aker Solutions asked DeRegt to reverse-engineer 25-year-old subsea signal cables on the Heidrun platform, and then qualify replacements to support the platform’s next 50 years of life. The twist: incomplete digital records, submerged load-cell cabling on tension-leg anchors (60–300 m), and concerns about seawater intrusion into legacy terminations. It was “never been done before” on an operating platform and would require a 2,000-page documentation pack to satisfy assurance. DeRegt had to recreate the design, verify it end-to-end, and deliver with full traceability.

Solution

DeRegt treated the job like a defense qualification program:

1. Forensic requirements capture. With 1990s records scattered across a basement archive, engineers reconstructed interfaces and operating envelopes from paper sources and field knowledge, then baselined them into a modern spec and verification plan.
2. Design for the real environment. The new cables serve load cells monitoring the platform’s tension legs, so electrical fidelity and long-term sealing had to hold while permanently submerged. The team addressed historical water “regress” (ingress) risks by updating materials (terminations) and re-qualifying sealing details for decades of exposure.
3. Fit, form, function, without legacy drawings. Reverse-engineering matched legacy geometry and connectors while applying modern manufacturing controls. Aker highlighted the precision of the surrounding subsea tooling: a 19-ton tool operating with just 2–3 mm clearance, so tolerances and assembly sequencing were engineered accordingly.
4. Defense-style verification & validation. The team produced a 2,000-page dossier (requirements, analysis, materials, inspection/test plans, acceptance evidence). That level of rigor de-risks installation on a live asset in harsh water and mirrors defense expectations for design-verify-validate discipline.

Why this matters beyond oil & gas: platforms, submarines, and towed systems often rely on legacy cabling with thin documentation. The Heidrun approach (recover the truth, re-engineer with modern sealing and materials, and prove compliance on paper and in hardware) maps directly to Defense & Security programs that must extend life safely, not just “make something that fits.”

Result

Aker reports a problem-free collaboration: correct design, on-time delivery, transparent communication, and enough confidence to place a new order. DeRegt “proved they can make this cable,” and Aker has full confidence the system will operate flawlessly for the platform’s next 50-year life cycle. In other words: reverse-engineering wasn’t just successful in the lab; it satisfied the operational owner responsible for a live, offshore asset.

For Defense & Security stakeholders, the transfer value is clear: if you can recreate, qualify, and document decades-old subsea cabling for a tension-leg platform under real production constraints, you can apply the same through-life engineering to sonar, towed arrays, surveillance nodes, and other mission systems where sealed terminations, stable signals, and documentation traceability decide mission outcomes.

Expert view