Gallery

WindFarm Service Vessels

Ad hoc Marine Designs Ltd. has been engaged in many Windfarm projects in recent years, ranging from simple consultancy through to design of Windfarm monohulls and catamarans for very demanding duties.

In addition to the 24m FastSwath we have designed a range of SWATHs from 23m up to 50m for both Windfarm and Offshore Oil industry operations as workboats and crew boats. The exposure to rough seas for many hours can fatigue the crew and their technicians can be left feeling seasick and render them unfit for work; especially in the harsh and extreme weather conditions of the North Sea during the winter season. These SWATHs have been specifically designed to ensure all year round operability and safety for the crew. The ability to keep station and maintain service speed in ever increasing wave heights with benign motions is where a SWATH is without equal.

SWATHs

So, what is a SWATH?..it is an acronym for Small Waterplane Area Twin Hull; SWATH. It is a hull form that offers superior seakeeping over a conventional hull form such as a monohull or catamaran. It is essentially two (or sometimes four) thin struts that have 2 (or four) buoyant tubes below the surface. These thin struts have a much reduced waterplane area when compared to conventional vessels and this lower waterplane area decouples the motions of vessel from the waves. The seakindliness of a SWATH is not just slightly better than a monohull but several times better. Put another way, the motion of a SWATH will be similar to that of a monohull many times its displacement.

Below is the mid-range 32m SWATH.

Our range of SWATHs allows for safe and comfortable working conditions in Hs of 3.0m and without the requirement to slow down. Year round operations can be performed in safety and comfort. Existing WFSV catamaran vessels in the 15-25m range currently working in the Windfarm Sector are simply unable to cope with the sea states when going further offshore and also in winter seasons. More details can be found in the Windfarm section.

Catamarans

With decades of experience in multihull designs in the Fast Ferry industry Ad Hoc Marine Designs has designed a range of Catamarans from 13m up to 26m designed to carry greater loads and be more versatile. Our most recent WFSV used our multihull expertise to satisfy a conflicting Statement of Requirements (SOR) namely: light, fast and able to carry heavy loads. This resulted in ‘Ashera’ operated by C.Truk with their unique modular wheelhouse.

For the more inshore and less weather dependant roles these small catamarans offer a wide range of solutions, a typical 26m WFSV is shown. This has been tailored to meet German Regulations. This and other catamaran designs by Ad Hoc can be designed to suit your exact requirements upon application.

41m SWATH Crew Boat for Offshore Oil Platform

Servicing and supplying crew to offshore oil platforms requires safe and comfortable operation year round in all sea states. The sea states experienced at these offshore oil platform locations are of the same magnitude as those at offshore windfarms, if not more. The remarkable seakeeping ability of the 41m SWATH ensures safe and comfortable operations. The vessel’s motions are further reduced by the use of an active ride control system which results in year round operations in significant wave heights of 3.0m with service speeds up to 28 knots. Damping appendages are also integrated into the hull form to maintain these levels of comfort when stopped at station.

The general arrangement of the 41m shown is in the Oil Platform crew transfer configuration and is designed to satisfy ISO 2631 sickness criteria in all service conditions and meets DNV’s R2 Crew Boat rules and the HSC 2000 code while transporting 134 passengers in safety and spacious comfort for both passengers and crew. A brief specification of the vessels particulars is also provided.

Other vessels

The design can be considered as a starting position for discussions or simply a request for a repeat design of that shown. Details of the designs, General Arrangement and Specification, are available upon request.

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