Fri 6 Feb 2026, 08:30 GMT | Updated: Fri 6 Feb 2026, 08:35 GMT | Evangelia Fragouli

Longitude unveils compact PSV design targeting cost efficiency


Design consultancy launches D-Flex vessel as a cost-efficient alternative to larger platform supply vessels.


D-Flex PSV design render.
Longitude's D-Flex design aims to deliver economic value through reduced capital and operating costs for shipowners. Pictured: Render of a D-Flex platform supply vessel (PSV) design. Image credit: Longitude

Longitude has unveiled a new compact platform supply vessel (PSV) concept designed to deliver lower capital and operating costs for shipowners serving offshore energy markets.

The design consultancy said its new D-Flex vessel is intended as a cost-efficient alternative where larger PSVs are not commercially suitable. The DP Class 2 vessel measures 74.7 metres in length and 16.2 metres in width, with a deadweight of 3,000 tonnes and a total deck area of 650 square metres.

The D-Flex is the second vessel concept in Longitude’s IMT Isca series and is an evolution of the operationally proven IMT 984 design. It is targeted at offshore energy operations in Asia, the Middle East and West Africa, with potential deployment in the southern North Sea.

Longitude said the design prioritises economic performance through reduced CAPEX and OPEX, while maintaining flexibility for different owner requirements. Layouts can be configured to include alternative accommodation arrangements, machinery choices and powering solutions, with optional preparation for future alternative fuels such as methanol.

Duncan Grigg, product lead for maritime design at Longitude, said the vessel was developed around commercial realities rather than theoretical performance.

The wider IMT Isca series is designed to provide adaptability across cargo configurations, accommodation layouts, machinery arrangements and propulsion options. Longitude said the platform is based on low fuel consumption and can be adapted for alternative fuels, including Tier III NOx-compliant solutions.

Longitude operates globally across ship design, marine operations, subsea and offshore wind projects, and forms part of the Oslo-listed consultancy group ABL Group.



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