Mission-Critical Defence Cables and Subsea Umbilicals

Fibron develops electro-mechanical and electro-optical tow cables for towed arrays, variable-depth sonar, mine-detection systems and other deployed acoustic or sensor payloads.

A towed sonar cable may combine a high-tensile mechanical member with power conductors, screened signal elements, telemetry channels and fibre optics. The design must account for tow load, hydrodynamic drag, cable catenary, torque balance, diameter, weight in water, bend-over-sheave fatigue and repeated launch-and-recovery cycles.

Steel-wire or high-performance fibre reinforcement can be selected according to strength, diameter, weight, rotational stability and handling requirements. Compact electrical cores, protected optical fibres and application-specific outer jackets help maintain reliable power and data transmission while meeting the limitations of the winch, sheave and deployment system.

Fibron’s experience in reducing the diameter and drag of demanding armoured tow cable constructions can also be applied where deck footprint, vehicle performance or hydrodynamic efficiency is critical.

Fibron designs ROV tether cables for inspection-class, medium and work-class remotely operated vehicles. Tethers can be configured for use between a tether management system and the ROV, or for direct connection to a free-swimming vehicle.

A compact tether may integrate electrical power, vehicle control, telemetry, video and fibre-optic data transmission. Construction is tailored around operating voltage, fibre count, required breaking load, diameter, length, minimum bend radius and buoyancy.

Neutral or positively buoyant designs can reduce tether drag and vehicle disturbance, while lightweight Vectran, aramid and other polymeric strength members can provide high tensile performance without the weight of conventional steel reinforcement. Jacket materials and construction geometry are selected to support flexibility, abrasion resistance, repeated handling and resistance to kinking or localised damage.

Fibron’s ability to adjust voltage, buoyancy, size, length and strength makes it possible to optimise the tether around the ROV rather than forcing the vehicle design to accommodate a standard catalogue cable.

The ROV main lift umbilical is the load-bearing and communications link between the topside launch and recovery system and the tether management system, subsea garage or vehicle. It must carry the suspended mechanical load while delivering dependable power, control, telemetry and high-bandwidth data.

Fibron manufactures bespoke steel-wire armoured and aramid-reinforced main lift umbilicals. Balanced armour constructions can be engineered to control torque and rotation under load, while conductor and fibre arrangements are configured around the power and communications requirements of the ROV system.

Design analysis considers working load, breaking load, weight in air and water, cyclic bend performance, crush and clamp loads, winch tension, sheave diameter, fleet angle, rotational stability and termination loads. High-voltage conductor systems can be integrated to reduce current and conductor size, supporting more compact umbilicals for deepwater or high-power vehicles.

Fibron has manufactured load-bearing constructions in continuous lengths of 10 kilometres and beyond and supports high-voltage umbilical designs operating at 6 kV and above.

Submarine rescue and intervention systems operate in circumstances where mobilisation time, operational readiness and personnel safety are critical. The umbilical must perform reliably after transportation, storage, deployment and repeated handling, often within a tightly constrained deck and launch system.

For tethered rescue vehicles, intervention ROVs and emergency support equipment, Fibron can design multi-service umbilicals integrating electrical power, control, telemetry, video, fibre-optic data and, where required by the system architecture, hydraulic or pneumatic services.

Engineering considerations can include operating depth, external pressure, suspended load, flexibility, cable diameter, deck footprint, reel capacity, launch-and-recovery compatibility, termination integrity and resistance to seawater ingress. Inspection, testing and manufacturing traceability are planned around the rescue system’s qualification and readiness requirements.

Fibron’s prototype capability is particularly valuable during rescue-system development, when vehicle interfaces, handling equipment and operational procedures may need to be proven together before the final production configuration is released.

Military diving umbilicals are human-life-support systems as well as mechanical and communications links. Their construction and reliability directly affect diver safety, mobility and the ability of the surface team to monitor and support the operation.

Fibron designs and manufactures defence diving umbilicals for surface-supplied air and Nitrox diving, saturation diving and bell-excursion operations. Depending on the diving system, an umbilical may incorporate breathing gas, pneumo or depth-monitoring hose, communications, video, electrical power, hot water and gas-reclaim services.

A helically laid, rope-like construction helps balance the component elements and provides the flexibility required for deck handling and diver movement. Hoses, cables, strength members and jackets are selected around working pressure, tensile load, abrasion, bending, temperature, buoyancy and resistance to kinking.

Fibron can provide a complete terminated assembly incorporating hose fittings, electrical connectors, grips, D-rings, bend protection and oil or water stops. Third-party testing or certification can also be coordinated where required by the contract or diving authority.

Mine countermeasure operations can involve influence sweeping, towed sensor systems, remotely operated mine-hunting vehicles and equipment used to identify or neutralise underwater threats. Each architecture places different electrical, mechanical and hydrodynamic demands on the cable.

Fibron can engineer tow cables, tethers and power-and-control umbilicals for magnetic, acoustic or combined-influence sweep equipment, mine-hunting ROVs and UUVs, towed sensors and related subsea payloads.

Design priorities may include tow tension, drag, seabed contact, abrasion, armour protection, power or current duty, signal integrity, control response, weight in water and repeated deployment and recovery. A magnetic sweep cable, for example, has a fundamentally different electrical and thermal duty from an electro-optical cable used with a mine-hunting sensor or vehicle.

By developing the construction around the specific mine countermeasure technique, Fibron can optimise the balance between mechanical strength, electrical function, hydrodynamic performance and compatibility with the deployment platform.

Sonobuoy cables form the compact suspension and electrical link between the buoy’s surface electronics and its underwater acoustic sensor, hydrophone or array. Cable performance can influence sensor depth, orientation, deployment behaviour and the quality of the acoustic data received.

For active and passive sonobuoy systems, design requirements may include a small packed volume, controlled deployment, sufficient tensile strength, compliant mechanical behaviour, stable sensor positioning and resistance to flow-induced vibration or strumming. Electrical continuity, signal integrity, water resistance and repeatability between production units are also important considerations.

Fibron’s experience with small-diameter composite constructions, high-performance strength members, electrical and optical components and prototype manufacture supports development programmes in which the cable must be tuned through testing and deployment trials.

Short-length manufacturing is especially valuable for sonobuoy development, allowing alternative materials, lay geometries, stiffness characteristics and sensor interfaces to be evaluated before the final construction is selected.

A helicopter-dunked or dipping sonar cable repeatedly lowers and recovers an acoustic body from a hovering aircraft. The cable must carry power and data while withstanding dynamic loading, cyclic bending, winch spooling, splash-zone exposure and full immersion.

Aircraft integration places strict constraints on cable diameter, weight, reel capacity and handling behaviour. Other key variables include tensile strength, controlled elongation, bend fatigue, torque and rotation, depth control, signal integrity, outer-jacket durability and compatibility with the sonar-body and winch terminations.

Fibron can combine compact power conductors, screened signal elements and fibre-optic components with steel-wire or high-performance fibre reinforcement. Mechanical and electrical verification can be tailored to the required deployment cycle, load spectrum and handling system.

Testing may include repeated reeling or bend-over-sheave cycling, tensile loading, torque and rotation measurement, electrical testing and post-cycle inspection of the cable and terminations.

Fibron designs bespoke high-voltage subsea power cables for seabed sensors, communications nodes, surveillance equipment, ROV and UUV support systems and other naval or defence equipment.

Products can be configured as dedicated electrical cables or as hybrid constructions combining high-voltage power with signal conductors, control circuits and fibre optics. They can also incorporate load-bearing strength members where the cable is deployed dynamically or used to support a subsea payload.

Engineering considerations include voltage stress, current-carrying capacity, thermal behaviour on a winch or reel, insulation thickness, partial discharge, electrical breakdown, screening, pressure and seawater resistance, armour, tensile performance, bend fatigue and termination design.

Fibron’s thin-wall conductor processing and high-voltage design and test capabilities enable compact constructions that can reduce cable diameter, suspended weight, reel size and deck-space requirements while maintaining the specified electrical and mechanical performance.