Naval architect Chartwell Marine has announced the launch of its market-first offshore energy support vessel (OESV) with hydrofoils.

Seacat Sceptre

Seacat Sceptre

The vessel was designed in partnership with marine design & engineering consultancy, BAR Technologies and uses the foils to partially lift the vessel in the water while running to reduce the hulls’ effective displacement and therefore reduce drag.

Seacat Sceptre, built at the Diverse Marine yard in Cowes, Isle of Wight, for UK OESV operator, Seacat Services, will now undergo sea trials prior to its handover.

Hydrofoils, re-popularised and matured as a technology in high-end yacht racing, lift the hull in the water in transit to reduce frictional resistance, thereby improving energy efficiency and stability. The Foil Optimisation and Stability System (FOSS), developed and patented by BAR Technologies, combines their America’s Cup heritage and expertise with Chartwell’s industry-leading track record in award-winning high-speed vessel design to resolve the mounting emissions and energy efficiency challenges facing the offshore energy support sector.

FOSS reduces hull resistance by positioning the lifting foil near the transom and controlling the running trim to ensure the hull is operating at its most efficient trims across the speed range. As well as contributing a 30% improvement in energy efficiency through wake reduction, FOSS improves seakeeping and handling through general motion damping, active roll and trim response, and improved manoeuvrability and stability in varying sea conditions.

Seacat Sceptre’s FOSS system is the first in this series of collaborative designs developed by Chartwell and BAR Tech, with a pioneering BARTech 30 vessel design anticipated for launch in the Summer of 2022. First orders for both designs have been placed by Seacat Services as part of the company’s ambition to lead the adoption of energy efficient vessels and technologies in offshore wind support.

The wet bits of Seacat Sceptre’s FOSS system

The wet bits of Seacat Sceptre’s FOSS system