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Regretfully postponed due to the Covid-19 outbreak and travel restrictions

Safehaven Marine are very disappointed to have to announce the postponing of our planned Transatlantic record attempt this year in Thunder Child II. This is due to global logistical and travel restrictions imposed as a result of the Covid 19 crisis that are likely to remain in place for most of this summer. Due to the very small Greenland sea ice and North Atlantic weather window that existed for us to make the attempt, it is not going to be possible for us to undertake the voyage this year.


Safehaven Marines ambition is in 2020 to set a new UIM approved Transatlantic World Record from the North American continent to Ireland. Traditionally there are three main routes possible. The first is a direct route from New York to the West coast of Ireland. This is the shortest route but it is a distance of 2,600nm with a leg of 1,670nm across the Atlantic. This leg would require a fuel capacity that is not possible in a vessel of our size factoring our cruise speed (40kts) or mid ocean refuelling, not allowed by the UIM. The second is from New York to the Azores, Portugal then Ireland. Although the longest leg across the Atlantic is less, at 1,300nm it is still beyond our range, and would be the greatest distance overall  at 3,650nm. The Third option is the Northern route, starting from Newfoundland, then Greenland, Iceland and down to the North West coast of Ireland. This route is the only real option open to us as the longest open ocean leg between refuelling points is 758nm, reasonably comfortably within the maximum range of Thunder Child II, the total voyage is 2,400nm. (4,500km)

Thunder Child.jpg

However the Northern route will prove extremely challenging beyond the usual challenges of any long distance open ocean speed record attempt for two main reasons, namely:

Storms. The geographical nature of the route in the high Northern hemisphere encompasses two of the worlds most active and potentially violent weather systems, the East coast of Canada out into the Grand Banks and the North Atlantic. Frontal systems form on the East coast of America and track Eastwards across the Mid Atlantic and frontal systems that form in the Labrador sea off Greenland and track East across the North Atlantic in a constant pattern, they either dissipate or intensify in to storms that track East across the Mid or North Atlantic until the hit land over Ireland and the UK after which they generally dissipate. However with modern forecasting it should be possible to time the attempt during a settled period and considering the general 3 day mostly guaranteed accuracy of a forecast it only leaves two days of risk, and with luck as the run will be at relatively high speed we should be able to avoid or outrun any fronts, or at least avoid the worst of the system. However it must be accepted that we will encounter some bad weather at some point in the voyage, and there is a chance that we could be hit by a major survival intensity storm.

Sea Ice & Icebergs. The second major challenge of this route is sea ice and icebergs. The route brings us into the Arctic region, for 10mths of the year sea ice and icebergs in the Labrador sea off Newfoundland and the coast of Greenland makes any passage in the region far to dangerous for any GRP boat, let alone one travelling at 40kts. However the Southern coastal regions of Greenland and the surrounding ocean can be clear of ice from mid July till the end of August. This leaves a short window during which the attempt is possible. The attempt would have to be made before the start of September as from then onwards it is hurricane season and our route puts of in ‘Hurricane Alley’

Support. We will be looking for support from people at the refueling stops in the same way we had support during the Rockall run, this will help us greatly

Making a documentary video of the attempt is planned, so good quality footage will be be essential.  To achieve this we will undertake the delivery of the boat by sea to Newfoundland in advance of the attempt at slow time over a week and record the footage in advance, it would also allow familiarity of the coast and ports prior to the record run. One can only imagine the kind of footage that, from a scenery perspective alone would be quite spectacular. Undertaking the delivery voyage a month or two ahead of the anticipated record run date would necessitate slower passage speeds close to the Arctic Circle where sea ice risk is likely.

The risks associated with this attempt can not be underestimated. At such northern latitudes we are outside the range of any rescue service, and certainly in Greenland and the North Atlantic to Iceland there is virtually no safety net. Survival in a liferaft at these latitudes, even in the summer months would not be long and we are outside the shipping lanes. 


We planed upon making the attempt in July 2019, however fully completing ‘Thunder Child II’ to the necessary high spec for such a voyage proved too much of a challenge, as Safehaven have a full order book and obviously priority had to be given to customer crafts necessitating a delay until July 2020 for the record attempt. The delay, whilst frustrating, will allow adequate time to fully complete Thunder Child II and undertake the essential testing beforehand, which just wouldn’t have been possible to achieve this year. Although it was an amazing achievement for Safehaven to have designed the unique hull and developed all the production mould and build the demonstrator, itself presenting multiple design challenges from her quad Caterpillar C8.7 650hp engine installation coupled to France Helices surface drives, providing the desirable redundancy for such an epic voyage. All of this was undertaken in just 15mths from commencement of work in Dec 2017, unfortunately it proved just too tight timewise to have been able to undertake the attempt in 2019.


                                                                                                                      The Boat

XSV20 was developed as new model in our extensive range of commercial, private and naval craft.  The design is a high speed patrol / S.A.R and interceptor with a moulded length of 21.5m and a LOA of 23m (75ft). The hull design is extremely innovative (Patent applied for) and seamlessly fuses a hydrofoil supported twin stepped asymmetrical catamaran hull form with a wave piercing monohull, to create a hybrid design that delivers the rough weather and high speed dynamic transverse stability of a catamaran, with the steep head sea capabilities of a deep V monohull. in 2018 Safehaven undertook a 6mth R&D programme, during which we built 12 scale model variants which were extensively tank tested to optimize the designs performance characteristics and hydrodynamics.

'THUNDER CHILD II',  the first of class XSV20 our demonstrator and record attempt boat was successfully launched in mid-February and underwent extensive sea trials during the March and April during which she proved to have excellent seakeeping and performance during a range of trials in varying sea states right up to Force 10 and in 5m seas off the Atlantic coast of Ireland, she proved to be very sea kindly and soft riding with excellent stability. She was returned to Safehaven’s shipyard where final fit out and the installation of her Hysucraft hydrofoil was completed, and a stunning transformation made with a cool matt chrome gold wrap.


'Thunder Child II' is certainly a fabulous looking design and is Powered by four Caterpillar C8.7 650hp engines, which had the best power to weight ratio in their class, four ZF 325ATS twin speed gearboxes and four France Helices SDS3L surface drives, providing her with a maximum speed of 50kts+, and a 30- 40kts+ cruise speed. She has a range of 750nm+ at 30kts by utilizing her full capacity.

The craft has been designed specifically for long range ocean crossing voyages and will accommodate a crew of 5-6 with live aboard facilities comprising 6 berths in 4 cabins, a galley and two head compartments. A large long range fuel capacity is provided from a 8,000L main tank and reserve tank with the ability to transfer 2,000L of fuel via a transfer arrangement to a bow tank to optimize LCG for prevailing sea states.

Safehaven carefully considered the optimum propulsion solution for the vessel, and although waterjets are an excellent option, we determined, at least in this instance, that a quad surface drive arrangement was the best option. There was also a weight saving by using four smaller capacity engines, instead of two larger more powerful, but heavier engines. This in turn enabled the use of a smaller and lighter surface drive model. 


Other factors also came into play in the decision, factors that were unique to ‘Thunder Child II’ and her Transatlantic capability such as redundancy, if one engine is lost, it should still be possible to achieve planning speeds and stay underway, which wouldn't be the case with a twin engine set up. Also with a quad arrangement having four smaller propellers means that in rough seas when forced to slow down she is much smother and more responsive in heavy seas than a twin surface drive installation would be, that said the seas we tend to test her in can be pretty extreme and for sure, not the norm.  Also by using the lower gear ratio of the twin speed ZF 325ATS gearboxes, it is be possible to greatly unload the propellers in heavy seas when they inevitably become deeply submerged in large waves allowing her to be more maneuverable in big breaking surf waves.


The surface drives are manufactured by France Helices, the chosen SD3L model of drive weighing just 270kg and is superbly engineered, with all hydraulics and cables contained within the transom inside the hull. The units being almost like ‘engineering works of art’ and look very impressive mounted on the transom.


Surface drives are designed to run with only the lower half of the propeller submerged, and as such there is very low appendage drag. The drives are articulated, able to be raised or lowered to both trim the hull and adjust the props submergence, as well as steer with vectored thrust. Like all types of propulsion surface drives have their pros and cons, but for this application demanding both high speeds of 50kts and economy, especially in rough seas at transitional speeds, they were the best choice.  

France Helices surface drives 4_resize.j

We worked closely with  Shock mitigation seating manufacturer SHOXS who will be supplying military spec seats and using their expertise to ensures crew safety. Two of their Military spec 4600 series seats are fitted for the helm and navigator and four of their new X8 series seats for the crew, both with over 8" of suspension travel. A 27,000btu Air conditioning systems from Dometic ensures crew comfort aboard. The vessel trim and stabilization experts Humphree supplied four HE series Interceptors fitted on the transom, coupled to their active automatic trim control and full stabilization system ensuring the vessels trim is optimized and maximum ride comfort is achieved in rough conditions. Due to the designs wave-piercing capabilities the windows are supplied by Houdini using 22mm ballistic glass for the front windows, with all other windows in 12mm unbreakable polycarbonate to save weight.

DELL, 8West and Navarino provided the vessels electronic capabilities including satellite communication to enable the record attempt to be be tracked live and followed Worldwide, on a dedicated web site and app hosted by 8west consulting. The vessel is fitted with 2x Sailor Satcom Antennas supplied by Navarino integrated to DELL computers. 8 West are also installing multiple 'G force' sensors throughout the vessel to allow motions and accelerations to be recorded for validation and R&D purposes, taking advantage of the unique opportunity such a long ocean passage offers for research.

XSV20 is constructed from Scott Bader Vinyleter with a fully cored structure in E Glass, with specific carbon fibre and kevlar reinforcement to unsure a light but very strong structure designed for up to 6g loading's


XSV20’s unique hull design was developed to solve the head sea limitations inherent in traditional catamarans design whereby when a sea state exceeds a given size, steepness and frequency, waves, especially in head seas, will inevitably impact on the flat surface of the bridge deck causing slamming. On XSV20 the forward mono hull section comprising a wavepiercing  bow and very deep V midship section that seamlessly transitions into the catamaran sections, very effectively pushes through and splits waves, dampening  motions and preventing the flat surface of the bridge deck from ever directly impacting the water surface. The hull of course will by design fully wave pierce, the level to which is speed dependent, but in general wave height needs to exceed 3m before this begins to occasionally occur and to this end the superstructure is especially strengthened and incorporates 25mm ballistic glass for the front windows, with above deck fit out, arrangement’s and air intakes especially designed for this.

Integral to the design is the incorporation of a hydrofoil system, designed by Hyuscraft installed between the asymmetrical catamaran hull, (the asymmetrical form particularly advantageous in this respect) and as such lifts the hull 400mm at higher speeds allowing the forward monohull section to run mostly dry and clear of the water with very little wetted area, the monohull sections only coming into significant effect in larger sized wave encounter effect allowing the hull to cut through waves.The hydrofoil also significantly improves seakeeping as it very effectively damps pitching as well as overall hull motions in waves. The hydrofoil comes into effect for speeds of 30kts and over and provides excellent efficiency at these higher cruising speeds, with range  and fuel economy actually increasing the faster you go, the complete opposite of typical planning hulls.

The design also allows for wider load variations as the monohull section supports a significant percentage of the vessels overall displacement, and by virtue of its steep deadrise, buoyancy rises exponentially supporting increases in displacement, thereby preventing excessive hull sinkage, which on a pure catamaran hull design results in a significantly reduced bridge deck clearance when heavily loaded. As such seakeeping in large waves at displacement speed when inevitably forced to slow down is excellent with negative impact on seakeeping, slamming never occurring on the bridge deck.


XSV 20 Principle dimensions / characteristics


L.O.A.                                                   23m / 74ft


Hull length                                         21.4m / 70ft


Beam overall                                      5.4m / 17ft 7"


Draft                                                   1m / 3.2ft


Displacement lightship                    23,500kg


Fully loaded                                       29,800kg


Fuel capacity                                      8,000L


Range                                                  750nm+


Crew capacity                                     6-10

Seating                                                6x SHOXS  Shock mitigation seats + 4 fixed (2x 4600 series & 4x X8 Series)

4x suspension reclining seats


Engines                                               4x Caterpillar C8.7 650hp

Gearboxes                                          4x ZF 325ATS Two speed

Surface Drive                                     4x France Helices SDS3L

Trim control/stabilization                Humphree

Air-Conditioning                                 Dometic


Speed Maximum                                54kts


Cruise speed                                     30- 40kts

Survivability                                       8x watertight compartments

Satellite communication                   Navarino 

Windows                                             Front 22mm Ballistic, side 12mm poly-carbonate.                     Houdini UK

Construction                                       FRP Composite- Scott Bader



High speed rough weather trials

Storm sea trials alongside our Interceptor 48 pilot Maskulin

Day of re launch in gold

Video featuring the engine and surface drive installation
Video of STORM BRENDAN video
Thunder Child  II in 'Storm Gareth'
Video of the first rough weather sea trials

Video featuring the hull construction

Video featuring the scale model R&D

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