Defence & Nuclear

Hydro Group Systems Inc specialises in providing total solutions to defence projects throughout North America and beyond. Parent company Hydro Group designs and manufactures electrical/optical connectors, hull penetrators, cable assemblies and terminations at its full-service factory in Aberdeen, Scotland.

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Hydro Group Plc specialises in providing total solutions to defence projects across the world. With defence applications requiring innovative subsea products, Hydro Group designs and manufactures purpose-built electrical and optical connectors, hull penetrators, cable assemblies and terminations at its full-service factory in Aberdeen, Scotland.

The defence arm of Hydro Group, comprised of Hydro Bond Engineering and Hydrocable Systems, has a track record stretching over 30 years. To date, sovereign and multinational organisations in the UK, USA, Europe and Far East have relied upon the Group’s expertise to manufacture and support subsea solutions through every stage of the product lifecycle.

Developed to exacting client requirements, our Submarine Through Pressure Hull Glands (PHG) and Equipment Glands have been successfully deployed on S, T and V-class submarines, with cabling compliant to stringent NES517 standards.

Typical applications have historically featured up to 50 fibre contacts, with three-phase 540 Amp, 440V power Pressure Hull Penetrator (PHP) applications. Featuring multiple connectors, composite connection interfaces can be made with electrical, RF and fibre-optic compatibility.  Advanced materials such as Inconel or aluminium nickel bronze are used to increase resistance to shock and impact, as well as oils, insulating gases, vacuum or low temperature scenarios.

Turret gland versions of the PHP can be modified further with mixed contact arrangements, ensuring an optimised solution for the task at hand, with Hydro Group also offering a range of bulkhead penetrators, tow cables and ROV cables/umbilicals for other applications.

Designed to carry an extremely high level of data, Hydro Group PHGs allow fewer penetrations of the submarine hull, thus increasing the integrity of the vessel and lessening the risk of water leakage. Inspection and maintenance can be greatly reduced over the submarine’s life cycle, which is often in excess of 30 years.

Other Hydro Group defence projects to date have included general instrumentation cables for NATO naval surface ship speed data loggers, heavy and light tow cables for a European naval force and connector-ready harnesses with hybrid power, communications and video cable assemblies for third-party defence contractors.

Please get in touch with us at to discuss your precise subsea defence requirements.