26m Typhoon Class Swath repeat order for R.E.S. build by Alicat Workboats & South Boats IOW

Ad Hoc Marine Designs Ltd is pleased to announce the signing of a new build contract with Alicat Workboats & South Boats IOW Ltd, with their 26m Typhoon Class Swath for Renewable Energy Support with the vessel MCS Swath 2 to be managed by Maritime Craft Services. This award proves that SWATH technology can be built in the UK cost effectively.

This design is an evolution of the first MCS Swath 1 vessel, which has proven herself to be superior in all seas states, and able to transit transfer safely in Hs=2.50m.

The mk2 has subtle changes such as: MCS Swath 2 is a quad drive, using 4xScania DI16 engines, with 2 per hull driving through a Hundested gearbox, which offsets each engine fwd and aft high up in the haunch, for easy maintenance from the main deck hatches. With the CPP system supplied by Hundested, with their unique offset angle entry input into the pitch control unit from the angled carbon fibre shaft.


The motion control system uses the Island Engineering system that has proven to be fully effective on MCS Swath 1 with accelerations no greater than 0.10g in Hs=2.0-2.50m in all sea headings and their unique zero speed heave dampening mode which has demonstrated the following reduction in motions:-

Up to 58% reduction in RMS pitch rate, 70% reduction in RMS pitch angle and 70% reduction in RMS bow vertical displacement

Thus clearly highlighting the “lightly damped” hull form of a Swath vessel is easily to manipulate and control, which removes the need for any heavy expensive and bulky motion damped platform. Thereby leaving the foredeck clear for working.

With a service speed of 24 knots and a payload of 33 tonne, carrying 24 technicians, 22,200 litres of fuel and in various configuration’s up to 4 x ISO containers and satisfying both the Workboat Code and HS-OSC code, is the next generation and evolution of the Ad Hoc Marine Designs Typhoon Class of Swath.

34m Low Wash RoPax Ferry

Ad Hoc Marine Designs owing to their vast portfolio of proven fast ferry designs ranging from 20m up to 60m has been awarded a contract to develop a 34m low was medium speed ropax ferry for a European client. More details to follow..






Renewable Energy Support Ltd (RES Ltd) takes delivery of 26m Typhoon Class Swath Crew Transfer Vessel – MCS Swath 1

The Ad Hoc Marine Designs Ltd. 26m Typhoon Class Swath ordered by Renewable Energy Support Ltd (RES Ltd) has been successfully delivered to operators Maritime Craft Services (Clyde) Ltd (MCS) after completing final sea trials in July in Taiwan.







The design, by Ad Hoc Marine Designs, of the 26m CTV Swath is an all-aluminium light weight robust & durable construction to BV class and MCA regulations and is based upon the experience of previously proven swath hull designs. It is uniquely designed to satisfy both slow speed and loitering operations at the turbine as well as high speed. This unique hull form satisfies these two competing requirements that resulted in an advanced Swath hull form with 20% increase in displacement, 50% reduced coupling and 20% increased damping without sacrificing resistance. It has been tailored for the demands of the Windfarm market. Designed to run in Hs = 2.0m at service speeds of 25 knots without any speed restrictions or uncomfortable motions that is associated with conventional vessels.








The operational role is enhanced by a powerful Island Engineering Motion control system that reduces seasickness, fatigue and vessel downtime to a minimum annually. It also features an advanced heave dampening mode that significantly reduces heave when at idle or stationery at the tower. Driven by two Man D2862 LE 466 diesel engines rated at 1029 kW IMO Tier 2, EPA Tier 3 compliant with a simple lift out from engine room via a hatch on the main deck. Each engine drives a Centa carbon fibre shaft to minimise weight coupled to a heavy duty Hundested CPP propeller.

On the first rough sea trial the vessel performed beyond expectations, which prompted Dirk Kuyt of MCS to state:

“During sea trials with the MCS SWATH 1, in Beaufort 4-5 from Southerly direction, off Suao Port, Taiwan I became aware what a 100% SWATH is all about. With wave height of 1,5 – 2 m,  there was no motion or acceleration at all and when at full speed putting the rudder hard over no heeling occurred. Truly amazing! Maximum speed in front of everything 27′ and average of 25’/hr. All main machinery are just below main deck for easy maintenance and in my opinion this is the best SWATH CTV in Europe or best CTV in Europe full stop.”

A build and final sea trial video of the 26m Swath CTV MCS Swath 1 taken during the tail end of Typhoon Nepartak on July 12th 2016 is shown here:








11m Hydrographic Survey Catamaran


This Ad Hoc Marine Designs 11m aluminium catamaran was recently delivered to Macao harbour authority for hydrographic duties. It is powered by 2 off Yamaha 250 HP outboard engines and carries up to 6 technicians in speed over 20knots in local conditions up to sea state 3. The hulls are divided into 3 watertight compartments, with the deckhouse comprising of seating, toilet and air conditioning for the technicians. This 11m catamaran was built at Lung Teh Shipbuilding in Taiwan.

LTS has a reputation of delivering high quality vessels and this 11m is another fine example along with their renowned attention to detail. Whether in GRP, Aluminium or Steel, LTS has a very competitive price structure and now coupled with increased investment and facilities into the yard are able to build the full range of vessels on offer from Ad Hoc Marine Designs, ranging from: Fast Ferries, Crew Boats, Windfarm Support Vessels, Patrol Boats to SWATHs up to lengths of 70m.

60m Floating Dry Dock

Ad Hoc Marine Designs has designed a floating dry dock. The dry dock is unique in that it is a multipurpose dock. The principal design of the dock is to accommodate a vessel with a maximum displacement of 600 tonnes and a maximum draft of 3.50m. To ensure maximum revenue earning capability, the dock can be split into two separate units of 35m and 25m. This allows greater flexibility and range of vessel that can be dry docked. The dock when joined together to make a 60m dock is shown below, while launching a large catamaran.













15m SWATH Workboat

Ad Hoc Marine Designs have used their expert knowledge in swath design to create possibly the world’s smallest SWATH workboat. This 15m Workboat SWATH is for an Asian client where seakeeping is a high priority. Workboats are often at sea for many hours in all sort of hazardous conditions for the crew which can easily lead to fatigue and tiredness. Having a vessel that does not “throw you about” with increasing sea state whilst performing very detailed work, a SWATH was the obvious solution.

With an overall length of 15.10m and a service speed of 12 knots, this 15m Workboat SWATH is one of the smallest commercial SWATH designs in the world. The 15m Workboat SWATH is driven by two Perkins Sabre M215C 6 Litre engines rated at 157kW @ 2500 RPM through a ZF80A 2.5:1 reduction gearbox to a 3 bladed propeller. The engines are located in the haunch. The structure has been designed to DNV HSLC rules and construction is in all aluminium. A new feature of this SWATH is an evolution in the hull design to enhance the superior seakeeping characteristics whilst maintaining a simple build methodology whilst minimising drag.


19.5m SWATH Windfarm Vessel Hull form for C.Truk

Ad Hoc Marine Designs was awarded a contracted by C.Truk a UK Windfarm Builder/Operator to supply a SWATH hull design that provides speed with seakeeping. A SWATH is an ideal platform for use in the Windfarm industry especially in the tier 2 & 3 farms that are being located further offshore.

Details of CTruk’s CWhisper SWATH vessel may be found here:

Ad Hoc Marine Designs are experts in SWATH design and were selected for their expertise and experience of previous successful working SWATH designs. This hull form is a scaled down version of the all new 24m FastSwath which has been specifically designed by Ad Hoc Marine Designs Ltd for the Windfarm market. More details of the 24m Fast Swath can be found here.

16m Windfarm Service Catamaran for C.Truk, UK

16m Windfarm Service CatamaranAd Hoc Marine Designs created many concepts before arriving at a solution for C.Truk. This 16m Windfarm catamaran had the design brief of being, light, fast and able to carry high loads, as well as the usual turbine duties. The design was to incorporate the unique “flexible pod” wheelhouse units that C.Truk has developed for the fast turn around and multipurpose capabilities making the design suitable for many different roles in the Windfarm sector. The vessel called Asherah (and is also the basis for the later 2m stretched verison called the 20T MPC  noted here ), is made of composite hulls and an aluminium extrusion deck. The vessel satisfies MCA Category 1 in the SVC code. A write up of the vessel may be found in the publication July edition of “Ship & Boat” from RINA. More details may be found here.

Rederij Doeksen, Holland

Ad Hoc Marine Designs were contracted to investigate the feasibility of stretching 2 existing vessels in their fleet by approximately 10 frames. One being a 45m and the other a 60m RoPax vessel. The investigations focused upon the “will it pass Class structure rules without major changes”, weight study to establish the new weights, the stability and hydrostatics to ensure Flag compliance as well as speed predictions. The results provided sufficient information for Rederij Doeksen to make an informed decision about future possibilities and growth within the company.

Rederij Doeksen, Holland

View of changes to engine girder to suit new engine.View from under the raft of new bow fenderview of new high speed ruder system

Having purchased an ex-FBM vessel, Rederij Doeksen approached Ad Hoc Marine Designs, the original designers, of their 50m catamaran. Providing advice on performance between the original Paxman to MTU engines, altering the engine beds to suit the new arrangement, all to Class. Designing a high speed rudder system to allow turning on rudders not the jets giving an increase in straight-line speed. Strengthening up the bow to become a fender. The fender allows the Master to ‘bump’ onto the fixed piles for ease of berthing. Finally arranging the new Safety plan, after Rederij Doeskeon changed the entire layout to suit their varied role.


“With their wealth of experience, especially in designing high speed vessels, Ad Hoc Marine Designs Ltd. was the obvious choice to turn to, when our company acquired the FBMA built fast ferry Supercat 2002. As we had plans to completely rebuilt the vessel, and re-engine her at the same time, and do this all under our own control, we needed all sorts of advice and someone who could provide us with new or modified drawings. Starting with speed/power predictions to determine engine size and consumption, up to a modification of the existing safety plan. Acting as our design office and consultancy, Ad Hoc Marine Designs Ltd. provided us with detailed drawings for the new engine beds, advised us on the repositioning of the transmission, calculated, designed and made drawings for 2 high speed rudders supplementing the water jet, and allowing us to run our specific route steering with just rudders. Advice was given on the down sizing of the existing skegs of the vessel. As we wanted to rearrange the interior it was found necessary to reposition some of the pillars. Based on our input, and wishes, a solution was found, including extra deck beams, and repositioned pillars to ensure the structural integrity.
In short; Ad Hoc Marine Designs Ltd. is a versatile partner whenever you want to build or rebuild a vessel, from SWOT analysis to conceptual decision making , as well as designing your vessel or assistance during the building process.”

Henk Boorsma, Rederij Doeksen, Holland.

Lockheed Martin, USA & FBMA Inc, Philippines

View on hull structure, during build.SLICE® vessel undergoing ballast trialsActing as the chief designer and providing full design technical support during the construction of the SLICE®. Having previously assisted in the design of LM’s SLICE at FBM Babcock, Nigel Warren, acted as Chief Designer and, John Kecsmar senior naval architect, continued their design and technical support as well as on-site technical support during the construction of the SLICE® vessel under the new company of Ad Hoc Marine Designs Ltd. This also included basin trials and inclining experiment.


TT Boat Designs, UK

Von Mises membrane stress plot of a DNV Pitch Connecting MomentAdvising on the detailed structural design of aluminium structures for their very successful range of vessels. This included FEA analysis and detailed reviews of structural joints etc of various catamarans all with varying roles. The FEA reports were for Class and Flag approval of the structure drawn. Also combined together to assist in the design of an 18m GRP Fast Patrol Boat for the Indian Customs, built by DMS in Malaysia.


“Ad Hoc Marine Design Ltd have provided assistance on a number of projects in recent years and their expertise in stress analysis in general, and the detail design of aluminium structures in particular, has been invaluable. With so many aspects of design becoming increasingly specialised Ad Hoc Marine Design are sure to be involved in many of the company’s future projects.”

Arthur Mursell, TT Boat Designs

South Boats, UK

Various catamaran hull designs for tank testingView of windfarm vessel 'Offshore Progress'View of windfarm vessel 'Solway Spirit'Undertaking sea trials of several of their windfarm catamarans. Advising on performance issues, undertaking model tests of two different hull forms, comparing regulatory issues between HSC, EU and Workboat Code, undertaking structural designs.

Clyde Marine Services, UK

Clyde ClipperAd Hoc Marine Designs provided tank testing resistance and powering data of a 24m Passenger catamaran called Clyde Clipper.

“..the speed on her sea trials was exactly as predicted with your testing and computer analysis….” Hamish Munro

Subsequently similar tank testing has recently been done on a projected landing craft design.


Thornycroft & Giles, UK

Designing structural foundations for cranes being used on a barge. The foundations were to be integrated into the main structure without creating any additional weight or losing space envelopes. The cranes being very heavy duty required significant stiffness to transfer the load efficiently.


Thornycroft Maritime & Associates Pty Ltd., Australia

Launching Cradle for 51m Patrol BoatLifting and Turning arrangement of 51m Patrol BoatHaving won a successful order for several 51m Patrol Boats, TMA employed Ad Hoc Marine Designs Ltd. to design the light weight steel structure of this high-speed patrol vessel for Indian Customs. Also advising on many smaller special projects including heavy lifting and turning of hulls and using FEA analysis for Class approval of structural designs.


Wind Farm Service Boats

We have been using our extensive knowledge and experience to design many different types of Wind Farm boats. The concepts are all unique, and draw upon our experience with a large variety of designs and working practical solutions.

Additionally, Ad Hoc Marine Designs sits on several technical committees and institutions and has a direct links into Flag and Class. This has enabled Ad Hoc Marine Designs to tackle the issues of what Class notations and what Flag authority safety standards the vessel must comply with and, what practical and cost implications this has on the design and operation.

One of the most interesting concepts recently to emerge is that of exploring methods for the transfer of the technician from Boat to Tower. Ad Hoc Marine Designs has developed a unique transfer brow system that solves one of the many safety issues that concerns this hazardous operation.

K&W Trans, Holland








Designing a unique fast multicat multipurpose vessel. This is a 38m catamaran for operation in the North Sea. Further details regarding the vessels operation can be found on K&W Trans, Holland.  The General Arrangement is shown above:

A video of the design has now been produced. This can be found on the K&W Trans website, alternatively can also be found here:

FBM Babcock Marine, UK

Working with their ex-colleagues at FBM, to design an extendable walking platform, or Brow, for transfer of crew/personnel between a vessel and a Wind Tower for maintenance. The Brow required design from first principles as well as a safety case study for Class/Flag approval.

MEF Babcock, UK

View of Rib Rack walkwayGeneral Arrangement of PontoonsDesigned modular floating pontoons for the Royal Marines base for berthing 30m landing craft in an exposed location. The pontoons had to take into account the extreme movements between each pontoon and the loads imposed by each to its adjunct pontoon. The general arrangement and construction drawings were completed to suit the tight financial budget. As-fitted drawings for a RIB Rack were also supplied.

EuroShip Services, Holland

General Arrangement of 26m windfarm catamaranDesigning a 24m WindFarm catamaran. This vessel is to support the new Windfarms being erected in the North Sea. The vessel is 26.35m overall on a waterline length of 22.73m. The hull form is of catamaran configuration with special emphasis in the bow shape to cope with working year round in the hazardous North Sea environment. The vessel has a large aft deck with a deck crane with a 5.5m reach. The saloon has seating for up to 48 crew/passengers which can be removed for greater cargo storage when required. There is also a small accommodation below decks of 2 berths port and starboard.


Babcock – Marine & Technology Division, UK

Providing structural analysis and solutions of various projects. Detailed structural analysis and calculations as well as writing reports and findings of FEA studies all for Class approval have been supplied.

Other Miscellaneous Work

Lifting Cradles being constructedUS built FBM TRICAT being lifted onto a ship for transportationDesigning a heavy lift frame work structure for transporting a large 50m Catamaran from the US to Hong Kong via a lift ship. Having advised and designed the cradle for lifting, onsite support during construction of the cradle to ensure the lift went as smoothly as possible. Further details of other lifting operations can be found in FastFerry International, September & October 2009.

Self propelled SWATH model for seakeeping analysisCatamaran during resistance tank testingIn-house design of new hull forms for low wash lower
resistance as well as personal interest and experiments into deck diving of catamarans, often referred to as bow diving. A brief summary of the deck diving experiments can be read in FastFerry International, June 2006.

Palmer Johnson Yachts, USA

Superstructure lifting arrangementCradle for transporting and launching vesselDesigning a lifting arrangement and frame work for a superstructure of a large motor yacht. The superstructure being fabricated from very thin plate and being a wide long structure required careful planning in the lifting and designing of the lifting arrangement to prevent any distortion and buckling to the thin scantlings.

Having their vessels constructed some distance from the location of launch, Ad Hoc Marine Designs provided Palmer Johnson with various solutions to the lifting and transporting of the finished vessel on to a specially designed cradle, for launching.


Schifffahrtsgesellschaft des Vierwaldstättersees, Switzerland

The FEM experiencing a DNV Pitch Connecting MomentClose view of the FEA internal structure highlighting stress concentrationsA river catamaran had been designed yet the major structural loads from the long slender aluminium hulls via the raft structure had yet to be established. Ad Hoc Marine Designs advised and reviewed the structural drawings and supplemented this analysis using FEA. A report and recommendations were given including locations for weight saving.

Anchor Trays

Design of a special purpose anchor and winch tray for Premier Shipping and Packing as a stand-alone anchoring system.

Dixon Yacht Design, UK

Using FEA to design foundations for chain plates on a large sailing yacht. The yacht was specially designed to be a “clean deck” which created such huge loads that the structure could have been compromised. Therefore the frames and plate required detailed analysis, for strength and fatigue.

Independent Reviews of Finite Element Analysis

View of vessel under a predefined load caseClose up of structural discontinuities showing stress concentrationsJohn has many years of experience of solving problems with FEA, for structural analysis, structural reviews as well as direct principal designs for global analysis. This experience has been used to clarify Classification Society FEA requirements and guidance to offer real practical solutions, not just analytical ones. Designs using FEA must eventually become real structure, and Ad Hoc Marine Designs provided real world guidance. Therefore, understanding FEA results and turning them into real structures to be fabricated has been foremost in Ad Hoc Marine Designs Ltd. capability for many years.