When I ordered this board I was hesitant about its width, volume and large wetted surface area and the impact that these could have on light wind performance. However after speaking to Patrice from Exocet he assured me of its light wind credentials.

When the board arrived I was a little taken aback by its sheer size, in particular its back end, which is huge! You can see from the photos that the rear end of the board has a formula board look about it. However the bow of the board is reminiscent of the original D2s but more aggressive in its shape.

The rails of the board for most of its length are rounded except for the last metre where they become square. This is much different to the 2011 Starboard Phantom design with its hard rails that assist with upwind angles.

Prior to the races I was only able to do a short test of the board and quickly noticed many similarities to sailing the old D2s, although with the wide back end it was much more stable. Like the D2s its upwind performance is exceptional with great height and pace when it hits its groove.

At my club racing I am usually in the top five although rarely winning. With the Exocet D2 I was able to set up a commanding lead in Race 1 and was ahead throughout the race. Despite a poor start in Race 2, which saw me towards the back of the fleet, the board’s outstanding speed in these light conditions quickly propelled me to 2^nd place. In Race 3, I was again able to win the race relatively comfortably.

In short, the new Exocet RS D2 Elite is a light wind weapon! Some of the key features of the board that give it this quality are:

• Its ability to sail a high angle upwind. In yesterday’s racing the board at times was sailing probably 5 degrees higher than my competitors.
• When the board hits its groove its straight line boat speed is very quick. I was probably travelling 10% quicker with the new board. Upwind in 5 to 6 knots of wind I was at times travelling around 8 to 10 knots.
• Despite the soft round rails, the board wanted to rail and sit on one side of its bow. As a result, while sailing upwind a third of the back end width was actually sitting out of the water. Which I think is reducing the weeted surface area?

Even in these light conditions the board showed good pace downwind. Sailing downwind in light conditions is not usually my strength however with the new board I did not lose any ground that I had made on the upwind legs.

A couple of other features worth mentioning are the center board action which is very smooth because of the new pedal and similarly the mast track action which is also smooth and silky.

So, based on the 3 races in light conditions I would have to say that this new Exocet RS D2 Elite board is looking to be an absolute winner.

I am hoping to trial the board in more wind shortly and will report back for Part 2 hopefully together with some videos.

“The Exocet D2″

This is the fourth in a series of articles I’ve written about raceboard design for LBWS and focuses on the recently released Exocet D2. I’ve primarily written this article to respond to those individuals that have asked me whether Exocet has copied my design.

To this end, I’ve summarised below my journey to get the ‘skiffboard’ in production:

24 July 2009 – Raceboard Design article published on LBWS

As a sailor with a passion for high performance sailing and as an engineer specialising in fluid dynamics, I’d been thinking about raceboard design since I started racing them about 5 years ago. Having been accustomed to the effortless glide provided by a skiff-like bow (with a vertical stem) while sailing Moths and 18 foot skiffs, I was tired of watching the bow of my Mistral Panam smash into wave after wave. I wrote my first article on raceboard design: See here

This article was grounded in theory and highlighted the importance of the relationship between drag and speed, particularly the ‘hump’. It also highlighted the success of skiffs in eliminating the ‘hump’.

Late 2010 – Discussions with Julian Bethwaite

In late 2010, I met and corresponded extensively with Julian Bethwaite of Bethwaite Design (bethwaite.com). Julian is, in my mind, one of the best in the world at innovative sailboat design, having revolutionised the 18 foot skiff class in the 1980s. I had hoped to work together with him to bring this design to market, but the market was too small for him to consider as an investor and he has a high workload in other, more valuable projects. Julian provided some excellent advice on the design of the board, and he offered his comprehensive services on a nominal fee-for-advice basis.

21 March 2010 – Explored joint venture proposal with manufacturers

I was keen to bring this design to market and had hoped to arrange a joint venture whereby I would project manage an R&D effort on behalf of a leading manufacturer, using Julian Bethwaite for design advice. Below is the email that I sent to Patrice Belbeoch:

Dear Patrice,

I am currently developing a new raceboard design and I am seeking a partner to help manufacture and commercialise this board.  I am hoping that Exocet is interested in partnering with me.

The design that I am refining is best summarised as “a skiff-like hull for a sailboard, with a wedge-shaped bow and vertical stem, but with a wide planning area at the stern”.  I have attached a rough sketch for your reference.  Furthermore, last year I wrote an article about raceboard design for www.LBwindsurfing.com :

http://www.lbwindsurfing.com/raceboard/raceboard-design/

I believe that my design has potential for dramatic performance improvement over the currently available raceboards: it will provide massive improvement in displacement mode with limited compromise in planning conditions.  Note that the design in NOT like a Division 2 board or other displacement raceboards because it has a wide and flat planning surface at the stern with hard chines.  I have been working with one of the world’s leading sailboat designers based in Sydney to further develop the board’s ‘lines’.

I am seeking a partner to bring this new raceboard design to market (funding, manufacturing, commercialisation).  I propose that I project-manage the development of the board (collaborating with the designer and the world-class test pilots that I have available), with Exocet providing funding and securing commercialisation/production rights.  The funding would pay for the designer’s fees and to construct the prototypes (cost only – I would not draw any income, but I believe my contribution of idea origination, project management and r&d should be acknowledged commercially).

Are you interested in discussing this opportunity?  I look forward to your feedback.

Regards
Richard

Below is the sketch that accompanied the email:

I also sent a similar email to Anders Bringdal (Mistral), Craig Gertenbach (Fanatic) and Tiesda You (Starboard). Each of these industry leaders engaged in correspondence with me and we exchanged thoughts on design and the market. The overwhelming conclusion was that the raceboard segment is too small to warrant significant investment. Such is life.

Patrice states that he never received this email. I tried to contact Patrice with via phone a number of times after sending the email, but each time I reached a voicemail message in French and I didn’t leave a message.

16 June 2010 – Raceboard article 2 published on LBWS

Although I abandoned the idea of working with a manufacturer to bring the design to market and making this a commercial venture (the demands of my ‘day-job’ also factored into this decision), I still believed in the design and wanted to progress it further. I wrote a second article for LBWS on raceboard design, which included a hand drawn conceptual design, similar to the design I sent to the manufacturers:

lbwindsurfing.com/journal/raceboard/raceboard-design-2

7 August 2010 – Forum thread started

The Raceboard Design article 2 generated significant interest and discussion. To further progress the discussion in a format that would allow posting of images, I started the following thread in the forum of LBWS:

lbwindsurfing.com/board/general-discussion/raceboard-design-1015

This initial thread became too large for the forum and was extended into the following thread:

lbwindsurfing.com/board/raceboard/raceboard-design-2-1156

26 February 2011 – Raceboard article 3 published on LBWS

I wanted to get the board built. The Australian Championships permits non-registered production raceboards to compete, as long as they conform to the raceboard rules. A few years ago, such a non-conforming board won the Australian Championships. I could build my board and still compete locally.

Although there were no local manufacturers willing to take on this project, I could take a CAD file to a CNC shaping bay and have the board shaped. I could finish off the detailed build myself. Hence I commenced fleshing out the design in a basic CAD program. When complete, I published the design in my third article for LBWS, including a downloadable CAD file with the design:

lbwindsurfing.com/journal/raceboard/raceboard-design-3

July 2011 – Exocet announce the D2

In July I became aware of the Exocet D2. The released image shows the design:

exocet-original.com/rs-d2-elite.php

Video footage has also been released:

EXOCET RS D2 2012 from eric bellande on Vimeo.

The Exocet D2 has the 2 core design elements of my ‘skiff-board’, being a wedge-shaped bow with a vertical stem, plus a wide, flat planning area at the stern. These 2 design elements have never been combined in a raceboard previously. To my mind, the Exocet D2 and my ‘skiffboard’ conceptual design are identical except for 2 subtle differences:
1. The Exocet D2 has the widest point further forward, whereas I retained a finer taper to further back on the board (like a modern skiff).
2. The Exocet D2 has a wave-piercing nose, whereas I have a vertical stem.

I emailed Patrice after I became aware of the Exocet D2 and have corresponded with him since. He states that he has not referenced my design in the development of the D2 and states that he never received the email I sent him in early 2010. I have not asked him whether he read the published articles on LBWS.

Exocet’s marketing message for the D2 consistently states that the D2 has been in development for many years. Exocet had certainly explored a comparable concept (although very different to the ‘skiffboard’ or ‘Exocet D2’) when they submitted the following design for the Olympics in 2008:

Image from boardseekermag.com/special_features/olymic_board_2/olympic_board2.htm

Future

Since abandoning the idea of working with manufacturers to commercialise this design (in mid-2010), I have continued to push this design because I want to see it succeed for non-commercial reasons. Above all, I want to sail faster raceboards.

I’m delighted that Exocet has brought this board to the market. I believe it will mark a major step in the evolution of raceboard design. I hope their D2 goes on to win many races and sparks other manufacturers to follow this design path. I will be buying one.

Has my conceptual ‘skiffboard’ design been copied? I don’t know; parallel development can occur and Exocet were certainly exploring comparable ideas. But it doesn’t really matter; I feel I have achieved my objective of having such a board in the market.

I am now turning my mind to the design of raceboard sails, where I have a design idea. I hope to publish an article on this for LBWS soon.

The Author

Richard Reatti (AKA ‘yagon’) is an avid sailor of Raceboards at Dobroyd Aquatic Club in Sydney, Australia. His sailing background includes extensive racing of skiff Moths and 18 foot skiffs, achieving top 5 placings in their respective world championships and he was the world junior champion in the Moth class. He recently placed 3rd in the heavyweight division of the Australian Raceboard Championships. He is also an engineer specialising in fluid dynamics.

Richard can be contacted at: richard@reatti.com.au

Modelling The “Skiffboard”

This is the third of a series of articles I’ve written about raceboard design for LBWS, or more specifically, about bringing to life a conceptual ‘skiffboard’ design. Since writing the last article, I’ve developed a 3D model of the design using Free!ship – a surface modelling program for designing ships, boats and yachts (and sailboards!).

The Overall Design

The board I’ve designed is similar to the conceptual design in my earlier article. The board is 3.75m long, 66cm wide and has a volume of ~285 litres. Below are some images of the model:

Plan View

The outline is (believe it or not) based on the outline of my Mistral Pan-Am, but with the last 500mm of the tail ‘chopped off’ and the nose extended by the same amount in the style of a skiff bow.

The tail of the board has a Vee shape that is typical of formula and slalom boards. This design enables efficient back-foot driving of the fin and keeps the tail width high, which helps early planing in the back straps.

Cross Section

The rear half of the board has a fairly traditional raceboard rail cross section. It has steeper ‘walls’ than the Pan-Am and closer to the rail profile of a Starboard Phantom. However, the top part of the rail has an edge that I believe will help release water, particularly when railing. The bottom of the board is flat for the last metre, then moves to a slight Vee in the centre of the board.

The front half of the board is, of course, fundamentally different to the currently available raceboards as it replicates skiff bow central to this design concept. It has a deep, rounded Vee and a vertical stem. I have developed this cross section through reference to the 18 foot skiffs (and 49er) that influenced this concept.

Profile View & Rocker

The profile in the back half of the board is comparable to existing raceboards. In the bow, the board has little rocker – a typical trait of successful skiff designs that helps with displacement sailing and wave-piercing qualities. The height of the bow is approximately 250mm, which equates to the nose being a little higher than the rocker of my Pan-Am, and quite a bit higher than a Phantom.

Design Refinement

I’d like as much feedback as possible to help refine this design – please post your thoughts in this article or in the forum topic on raceboard design. Alternatively, feel free to email me.

I’m particularly keen for feedback from LBWS members who’ve:
Sailed boards with similar design features like the Sabre
Been involved in 3D modelling

I can forward the Free!ship file (.fbm format) for your reference. A linesplan is also available.

Download ship file….here

I recognise that this design could be a challenging board to handle (eg potentially nose-diving in strong winds; slower turning), but I am confident that appropriate handling techniques could be developed.

Commercialisation

I have sent the design (the actual 3D model) to several board manufacturers. I’d dearly like to work with them to help bring this board to market, but based on my previous contact with them, I doubt they’ll be interested because raceboards are a niche market. My offer to the manufacturers as per my earlier article (to manage R&D) still stands.

I would also like to explore getting this board custom made. If you are a custom board building willing to take on this project (or know one), please contact me.

The Author

Richard Reatti (AKA ‘yagon’) is an avid sailor of Raceboards at Dobroyd Aquatic Club in Sydney, Australia. His sailing background includes extensive racing of skiff Moths and 18 foot skiffs, achieving top 5 placings in their respective world championships and he was the world junior champion in the Moth class. He is also an engineer specialising in fluid dynamics.

Richard can be contacted at: richard @reatti.com.au

This board came about being built because last year a 1988 customer of mine, called Norman Moore, had a sail for sale which I called about not knowing it was Norman. He mentioned that because it was 21 years since the Sabre, (designed by Sean Cox), had won the Worlds in 1988 and the Nationals in 1989. We wanted to see how the Sabre now compared to modern day boards. So armed with my 22 year old equipment, we went to Wimbleball Lake, in Somerset, to have a go. It did well and inspired me to go to a few other events and then, of course, the idea of this new ‘old’ board was firmly established.

At a meeting at the British nationals, it was agreed that prototypes would be allowed to race. Add to that the new raceboard rules, no further encouragement needed!

The plan profile was taken from a board drawn up in 1988, so it does make one wonder where Raceboards would be to-day had the rule makers not been so pro-factory boards . I tried to make the basic board from materials anybody can get hold of. The reason back then for drawing out this shape was that it was fairly obvious that Sean’s Sabre with its boat- like front was cutting through the waves better than anything else at the time. To improve on this, I drew the bow with a finer entry , a thinner bow and used a round section rather than a chine because my brother would fly past in light winds on a Div II board, therefore hoping to get the combination of both. The rules all changed and I never built it.

The new board measurement is: Length 3800mm; max width 640mm; max depth 200mm; tail width 400mm; Centreboard length 800mm from bottom of hull. I have drawn out another hull of 700mm max width as some have become to use to wide boards!

Construction

( refer to photo gallery here)

The stringer and centreboard casing were constructed from 4mm plywood. Epoxy with cotton flox was used as a glue.

The polystyrene was bought from the local builder’s merchants. I took some scales with me as the density according to the label varied between 10 and 40 KG. The average density worked out at 13kg/metre cubed. The blocks were stuck together using epoxy mixed with glass bubbles. Make sure that this glue stays 50mm within the drawn outline of the board on each block. This is so that it does not get in the way of shaping the blocks.

The blocks of polystyrene once cut out for each side of the board were glued together using 2 part expanding foam. The foam was stuck to the stringer using epoxy mixed with cotton flox. A slow expanding foam / glue would have been better. Best to remove 20cm of stringer (so total length of stringer is 360cm) as it gets in the way of shaping the front of the board.

To shape the board using an electric plane, use a dust mask cut to the correct shape and tape it around the air inlet of the plane. This will save your plane from premature extinction. When using the plane, go from one end of the board to the other, otherwise you will lose the continuation of the lines of the board, especially on the rails of the board. I also use surforms but the last part of the shaping must be with long sanding blocks. I have two. One is two foot long and the other nearly four foot long. At the end of the day as the sun sets, put the board in this light and what you thought was really good suddenly is not quite what you thought ! Good to make use of this light.

Make continued use of spirit levels. Use a plank of wood stuck into centreboard casing to check vertical and horizontal levels. Make the whole blank square before you even think about shaping it. You want the centreboard to be perpendicular to the bottom of the board.

By this I mean the rails perpendicular to the deck and bottom of board. If you try to bypass this then it is unlikely you will make an accurate board.

Rather than use high density foam in the footstrap area, mix up about 2 to 300 grams of epoxy, and squeegee and push the epoxy into the foam in the stern of the board for the footstrap area. I did this to the Sabres 22 years ago and they are still good to-day on my board.

My blank weighed 7.4KG unsealed and with no skeg box or mast track. It should have been lighter if I had done a better job glueing the stringer to the foam.

The mast track moulding was made by taping up and old mistral mast track with packing tape, shapeing the ends with plasticine and then a 3 X applications of release wax over the whole lot. The track was sunk into a smooth piece of plastic. Then used 3 x 200 gram woven cloth and layed it up. If I knew how to Vacuum mould, this would have been the time to use it ! This came out at 140 grams. The foam and stringer were routed out and then mast track moulding installed in the board with expanding two part foam with channels routed out for the expanding foam to escape as per the photos. Leave the mast track in the moulding while doing this to ensure the moulding keeps its shape. I managed to bring the track right back so that the back of the track is actually in the centreboard casing. Also lets the track drain.

Sealing the blank – This is very important as it saves weight and was very time consuming. In the past I mixed up some glass bubbles and epoxy, squeegeed the part I was going to lay up ( Bottom first), waited for it to go tacky then laid the board up. This time, because the polystyrene was not that good a finish, I waited for the glass bubbles to set, sanded it, filled it, sanded it, filled the bits I damaged myself, then realised the carbon was never going to go round the rails, radiused them, filled them and so it went on….. for nearly a week. Completely forgot that I use to radius the Sabre rails before shaping and then re-profiled once laid up. With mast track moulding installed and blank sealed, the weight was now 8.4KG. I reckoned I was still on target for 14 KG all up weight…..Bluddy dreamers.

As I had not used carbon before, I rang the supplier who said I should put a layer of resin on the board first and then lay the carbon on this. I stupidly laid the carbon cloth on the board and made a slit in the carbon where the centreboard casing would be, and could I get this carbon in the right place, could I hell ! Panic stations for the next 20 minutes while I lifted and re-laid the carbon. All ended well in the end. Needless to say, I went back to my old way of draping the cloth and pouring the resin over the cloth. You soon learn to see where the carbon is wetted out but not as easily as you can glass.

Carbon Lay ups in order.

1. Lay up the bottom of the board, 1 x 200 g carbon. Use masking tape along the rails to make a line to trim to. Once set, give a hot coat.
2. Lay up the top of the board, AND STRAIGHT OVER THE MAST TRACK, 2 layers applied one at a time, and drape the cloth with about an inch overlapping the bottom of the board’s rail. Trim carbon out the mast track area and Trim cloth to bottom of board when it reaches the toffee stage. Again give a hot coat.
3. Sand nose of board and Put two x 200 gram ‘patches ‘ wrapped around the nose for added strength.

MY FEELINGS ARE ALWAYS GIVE A HOT COAT AS SOON AS YOU CAN. I PARTIALLY SANDED THROUGH THE CARBON WITHOUT A HOTCOAT AND IT SEVERELY WEAKENS THE LAYUP. THE HOT COAT CAN BE RESIN OR GLASSBUBBLES/RESIN TO SAVE WEIGHT. I FEEL THIS IS VITAL SO THAT THE CARBON IS NOT DAMAGED THROUGH SANDING.

Peel ply is not vital but it can be very useful. Buy it at the fabric shop. It is called polyester lining.

Fin Box. A standard tuttle fin box , weight 315 grams was used.

First put fin in box and stand on board. Make sure the fin is parallel to the board. I think your eye and measuring is the best for this. Draw round base and then route out the carbon and foam. I used the strength of the stringer to put the box next too, but this meant the box was off centre by about 3 mm. Next time, stringer must be modified to keep in centre. Sand fin box to get rid of all shine and any release wax from its mould, then a glass bubbles /epoxy mix used to fill vertical slits in tuttle fin box. Applied release wax to fin, put fin in box and install box wrapped in pre-pregnated 2 x 200 gram glass cloth. I taped up the deck of the board using masking tape to stop resin draining out ( Board upside down to put fin box in). Use spirit levels to make sure board is level and to make sure fin is vertical and again masking tape to keep fin upright ( tip of fin to side of board)

Once green trim as much as you can and remove the fin. Turn board the right way up. I then filled the tuttle fin box with expanding foam, sanded it level with the deck ready for patches that would cover the top of the fin box and foot strap mountings.

Foot strap mountings, mast track mounting, and fin box.

Cut half inch diameter hardwood dowels into 50 mm lengths. Drill an oversized whole for a 30mm stainless self tapping screw, so that the screw just drops down into it and yes, you will wreck a couple of dowels by drilling out the side of it, if you don’t have a drill press. Drill half inch holes where you want to place the footstraps in the board, 4 dowels per foot strap spaced at 180mm x 25mm, and then fill each hole with glass bubbles/epoxy mix and push dowels into this hole. They will try to spring up, but hold them down as this pushes the epoxy into the foam. Once set sand flush with deck and make sure holes in dowel are clear. I then laid up 2 x 200 gram carbon onto plastic sheet and covered this layup with another plastic sheet. Cut out 100mm diameter circles with a pair of scissors, remove one side of the plastic and cover and place over the two footstrap dowels placed 25mm apart and squeegee down. Next, use a needle to find where the holes are in the dowel, make small circles to open up the weave of the cloth, mix up pure epoxy and use a syringe to fill the holes up in the dowel . Now with RELEASE WAX ON THE SCREWS, push the screws into the dowels. Resin will come up into the carbon patch and you will need a squeegee to remove this excess. Let the whole lot set, and remove the screws once resin is set. You should not have any problems with exotherming but don’t use a fast hardener for the dowels or the screws.

Exactly the same method was used for the fin box and dowels for footstraps by the fin box but using a larger patch.

The mast track mounting screws are made in exactly the same way but the glass strip to cover the doweling is the width of the molding.

The centreboard casing – 1 x 200 gram carbon cloth.

This was laid up after the top and bottom of the board had been laid up. This job is done with the board on its side and the casing level. Use a spirit level otherwise the resin will run to the lower point.

Firstly, make sure the casing is free from resin runs and radius the joints inside using epoxy and cotton flox. Sand with circular file and/or 80 grit to make a smooth radius.

A trim line is made about 100 mm parallel to the centreboard casing on top and bottom of board . This is just masking tape with one edge set 100 mm from casing on each side. Same is done on the bottom of the board. Cloth is cut to shape. Cloth on top and bottom of board taped outside of the masking tape so cloth can be pulled tight. Where there is quite a tight radius to make the flushing strip, I use square 10mm section covered in packing tape, then release wax. Once cloth is laminated, this square section strip is held in place with panel pins, and a hammer used to pin this strip into the corner of the flushing strip. This gives a tight radius . Once resin reaches toffee stage, give inside od casing a hot coat and trim to masking tape and remove tape. Let the flushing strip set for a day before unpinning the square section strips.

Air breather valve.

A standard Chinook air breather valve was used placed in front of the mast track

Final lay up

As a precaution, and also the worry of damaging the bottom of the board, and also re-inforce the sharp rails, I filled the edge of the board with epoxy /glass bubbles. If you are wondering where this is, because the rails were radiused, the first bottom layup wraps around a radius on the rails, where as the top layup hangs vertically down. This leaves a small fillet, but think this to our advantage as it gives the rail some added protection. One could lay some carbon tow, or strands into this for extra strength. Once filled a lay up of 1 x 200 gram carbon was laid up from the back of the board to 500mm in front of the centreboard casing in an arrow head pattern. The square section strips are left in the slot flusher and the cloth cut to this once at toffee stage. Again a hot coat applied as soon as possible.

Centreboard

Presently it uses an old repaired Sabre centreboard. I did make a centreboard which laminated weighed 510 grams. Unfortunately it warped and was no good to use. It was used for demonstrating to friends how strong it was by placing it between two chairs and standing on it – and yesterday decided to break after two weeks of torture ! The next one I will try shaping from Jelutong or Obeechi. Obeechi apparently is 25% less dense but have not tried this material as yet, but jelutong works very well and is a stable wood.

The flushing strip – was made to take 2 or 3 mm silicone sheet, but when it arrived, it was not stiff enough so we made it out of mylar sail cloth and alloy strip from ‘B and Q’ . Would like to use silicone sheet once we find the correct stiffness.

I will not leave the carbon as a carbon finish. It will be painted White by next summer. The heat from the sun on the board is just too much. From articles it seems that once the board has cured , if the board has a postcure, that is 5 hours at 80degrees centigrade this increases the tensile strength by 25%. Well worth doing.

Sailing the board

It has the about the same stability as the sabre but both of them are more unstable than a Phantom after having tried Bob Warrens at St.Mawes. However, this new board slices through the chop.

Click here to see photos on water.

My brother emailed me his description and feelings of the board.

New Long board
Having not sailed a long board for quite some…approximately 20 years, I was thrilled that my elder uglier brother asked to try out his new board.
The first day of the event was windy, and one of the main problems was not the board but the user. I spent several hours getting myself and the rig set up as best I could for the conditions.
I was using a Demon Design 7.5 from years ago (Steve Ireland K1402), so the sail was not the newer version, with the open leech.
This made sailing in 20 knots + bloody difficult.
HOWEVER, once I was a little more comfortable, I started sailing the board upwind. As you are all aware, with a wind of 20 knots, there is quite a small short chop. I was gob smacked by the way I went up wind. The first few seconds were amazing, because I watched the bow drove straight INTO the wave.I was expecting to be flung forward but was surprised that that ere was hardly any loss of boat speed whatsoever. The board did NOT ride OVER the wave…it went straight through it….it was bloody awesome. It is a true wave piercing board, and really comfortable.
There is no noticeable speed loss as you go through the waves, and that awful feeling of thinking you are going to be flung forward when the board goes into the waves quickly evaporated, and I actually started to smile, and continue sailing out of the bay, which was in the lee of the true wind and sailing bigger waves….same effect…straight through the waves.
Tacking with the track forward is not fast, but I am sure with more time on the water, she will tack easily. (Move the track back, and the bow lifts out of the water, and she will tack round more quickly.) However. I did point out to my brother that the tacks were a long arc into wind, so no ground was lost. Like everything, it is finding the correct technique to get the results you want (well that’s what my girlfriend keeps telling me!)
Downwind, track back, board up, it felt bloody fast, and again, I experienced that bloody awful feeling, but 20 times as bad, watching the bow disappear into the wave, and then being pleasantly surprised as the board continued forward. It is a strange feeling watching ALL the bow disappear under the waves, but after a few minutes you get used and start smiling again, and not worry that you feet a firmly in the back straps.
The first couple of gybes were a complete disaster, but gradually the cob webs disappeard out of the system, and I was starting to carve.
The main problem I had was that I was not fit enough to truly test this board. I buggered up the tendons in my wrists on the first day, so was nervous about the next day.
I did a few races, and with each race, the results got better, but it was me who was rusty as hell.

So, with a day of experience on the new board, in 20 knots,and after a 20 year gap in racing, I think we can say the board has the following
Wave piercing
Rails up wind
Planes downwind no problem at all

The next day, we had much lighter winds of about 6 to 12 knots.

I was using a Demon 9.5, which had been converted from a Formula sail…….

It was not planning conditions, except in the gusts.

Downwind, track forward, centerboard down…help stability…she is a little “tippy”, but my view on that is that if you want a thoroughbred then you have to put up with a few idiosyncracies.
Again, I was the problem….rusty as hell. But with little effort I was in the leading pack of the fleet, and starting to enjoy myself…I just wished my wrists were not in so much pain, because I could hardly pump, and the board was flying.
Upwind, I was hanging in there, but again, my technique was not right for the board, so I was struggling. I made the mistake of having short harness lines, weight on the board, not giving the board the opportunity to rail. So in one of the races, I was panicking, because I was not pointing, and losing ground quickly which was really pissing me off, and with screaming wrists, I was quite despondent. On the beach, I spoke to my brother and said I think we have some issues here. However that soon changed after the last race…..and a new technique.
The last race was a beat up an estuary, round a mark and downwind to the finish again.
Naturaly being rusty I did not dare fight for the prime position on the start line, but just tried looking for a clean start. We had a reach….non planning. I pumped, and the board took off…really took off.
Round the corner it was upwind. I forgot the harness lines. I stuck my arse right out, arms straight…remember the DIV II days in the marginal conditions, when you put all the load through the mast foot…that was it..
Board on the rail, going like a rocket.
After a few minutes, the only board in front of me, was Bob Warren on his Phantom, and I was closing down on him bloody quickly. By the time we reached the windward mark, I was right onto him….only to suffer a “rusty” moment….dropped the sail as I gybed…
She flew downwind, and I was finally starting to enjoy myself, even though arms were killing me, and over the line second….that was more like it!

The board is quick, but like everything, you need time on the water, learning how to sail her.

Future….
Get arms better, and spend a few days on this board, and go to another regatta…would be great to sail again, after knowing the board better

The dimensions of the board are to the new raceboard rules. It is 3.8m Long.
Volume I guess is in excess of 300 L. Max Width is 630mm, tail width 400mm.
I did make a centreboard out of insulation foam and laminated it in Carbon/ Epoxy. Unfortunately it developed a warp. Shame as it weighed at this stage 513 grams – lighter than the fin. Put it between two chairs and stood on it so its quite strong. Have to work on this one. Am going to try Obeechi next which is 25% less dense than Jelutong (which I normally use) and cheaper.
Anyone with a davidson DivII could take 10cm off the back of it – and it would fit the measurement rules !!!Probably applies to several other Div II boards and they would be quick in light airs.

Below – Video from day 4.

The 5th. Kona Worlds ended in spectacular fashion with blue skies and 20 knots. It was a thriller with the top 3 only separated with 3 points. Adam Holm (SWE) closed the gap even further by winning the first race of the day, but he was closely followed by Juliano Scalabrin (BRA) in second, while Monique Valle (CAN) “only” finished 5th….For a full review and results go to KONA-WINDSURFING.com

Raceboard Design 2 The “Skiffboard” – Conceptual Design

DESIGN
The overarching design objective is to the build a faster Raceboard: a ‘round-the-buoys’ sailboard conforming to the Raceboard class rules for use in 0 to 25+ knots. It would be used in a wide variety of conditions, typical of sailboat racing venues such as Sydney Harbour, and would need to be able to handle moderate-sized waves, and areas of light wind. It is an all-conditions racing board.
The overall design concept borrows heavily from the 18foot skiff designs (the pre-cursor of the Olympic Class 49er) of the early 1990s, hence the name “Skiffboard”. It has a long, sharp bow with a vertical stem and a wide, flat planning area at the stern. The design merges the bow of a displacement hull (such as the Starboard Serenity or Div 2) with the stern of a planning hull (such as a modern wide-ish slalom board).
>It would be 3.8m long, the maximum permitted length for the Raceboard class, and of a width equivalent to modern Raceboards. The diagram below shows a rough sketch of the concept:

This design as pictured above is preliminary and conceptual – it obviously requires significant refinement. However, I believe that this design concept (if refined) would provide superior all-round performance to any raceboard currently available. This superior performance would be driven by the reduction1 of the “hump” in the drag-speed curve¹, as discussed in my previous article on raceboard design.

POTENTIAL PERFORMANCE

In light winds, I believe that its performance would be significantly better than existing Raceboards because of its lower form drag (due to the fine bow) – its performance should be closer to a pure displacement hull than a modern Raceboard. In moderate winds, I believe that the wave-piercing abilities of its bow would continue its out- performance of existing Raceboards – in addition, it should outperform displacement hulls because it would plane earlier.

In strong winds, I believe that its performance would be comparable to the current crop of Raceboards. It would outperform displacement hulls in strong winds because it could plane on its tail like a slalom board.

However, handling may be challenging in stronger winds. I believe it may have a propensity to nose-dive while sailing downwind in chop. This can occur with high performance designs such as skiffs and catamarans. However, I believe that handling techniques may be developed to compensate and its potential all-wind performance would be worth this compromise.

Areas where this board maybe more difficult to handle is in manoeuvring/turning (particularly tacking and bearing away). The long displacement-profile bow may be difficult to ‘push’ laterally through the water. However, I don’t believe this would be any more difficult than the Div 2 boards of the 1980s and, again, handling techniques could be developed to adjust.

DESIGN CONTEXT

All of the above comments about performance are hypotheses, but based on first- principles hydrodynamics and from my experience in developing, racing and observing Moths, 18 foot skiffs and other high performance sailboats. This design concept is unproven² – it needs further refinement, particularly regarding the alignment of the shape to the key ‘numbers’ (rig & hull forces, weights, volumes, mast and centreboard locations etc), and then development / testing of prototypes.

I am not aware of any other truly comparable boards at the moment, although some designs have touched on this concept. This design concept varies significantly from a Div 2 board (displacement hull) because of the wide, flat planning area at the stern. It also varies significantly from the hybrid boards that were designed as potential Olympic boards because of its 3.8m length.

INDUSTRY SUPPORT

I am not approaching this as a commercial venture: I simply want to sail faster Raceboards and see the Raceboard class develop. To this end, I have contacted several of the leading sailboard manufacturers to try to make this design a reality. I have shared my design concept with them. In addition, I have even offered to co- ordinate further design / development and construction / testing of prototypes (effectively outsourcing their R&D for this board), while allowing them to retain commercialisation rights.

The feedback from the manufacturers has been positive regarding the design concept. However, they have not been interested in developing this board with me, generally stating that the Raceboard / lightwind market is too small and is considered a niche. This response is disappointing but understandable: they are operating a commercial enterprise.

While the big manufacturers may not find it attractive to invest in Raceboards, such investment might suit a niche or boutique sailboard manufacturer. I’m interested to talk to such parties and I would offer to co-ordinate further development if they’re interested.

Alternatively, perhaps an individual will take these design concepts, and build and race a board competitively. Unfortunately, the Raceboard class production rule discourages such innovation.

The Author

Richard Reatti (AKA ‘yagon’) is an avid sailor of Raceboards at Dobroyd Aquatic Club in Sydney, Australia. His sailing background includes extensive racing of skiff Moths and 18 foot skiffs, achieving top 5 placings in their respective world championships and he was the world junior champion in the Moth class. He is also an engineer specialising in fluid dynamics.

Richard can be contacted at: richard @ reatti.com.au

⁽¹⁾ I expect that eliminating the hump in the curve will not be possible for a craft as small as a sailboard, but I believe that this design will reduce the hump significantly.
⁽²⁾ Unproven in sailboards, however, this design concept has been proven in dinghies such as: Moths, 18 Foot Skiffs, 49ers, 29ers and others.

Kona Elite 380

This pure raceboard is an evolution of the Exocet Warp X380, a proven concept and top contender in the Raceboard class.

The “blueprints” inherited from the prominent Warp X380 was key when developing this exiting concept. All the positive characteristics of the previous design have been preserved and the conclusion is outstanding.

The Warp X380 was a board with astonishing speed and stability upwind, – yet we have succeeded in adding to the performance by moving all the appendices (fins and dagger ) further back. As a consequence the footstrap and mast track positions have been moved as well – giving the board a free feeling and blistering up wind speed. Although working well, the step tail was eliminated in the process – which admittedly makes the board better suited for today’s upwind -downwind courses.

With the fin positioned far back into a standard set up we also managed to decrease the size – adding speed both up and downwind. The Kona 380 E rides high and effortless through chops in rough conditions.

The volume has been increased by 15 litres and the VE has been altered to coincide with this innovative concept. A complete new package, delivering uncompromised speed and pointing abilities, being produced in a new high tech construction and delivered with a top of the line racing daggerboard.

We hope you will enjoy the board as much as we enjoyed developing it.

This press release was taken from kona-windsurfing.com

Specs;
Volume 310 litres
Length; 380 cm
Width; 65 cm
Weight; 13 Kg
Fin size and box; 40 cm Tuttle box
Mast track; Adjustable
Sail size; 6.5 to 9.5

Windsurfer One Design American National Championships (aka: The 12th Annual DINO Race) September 26th, 2009

This grass roots event was organized by the fleet of Windsurfer One Design enthusiasts outside of Houston, Texas and attracted 30 sailors.

Six races were held in light to moderate winds. The 30 sailors were divided into three classes. Starts were alternated and sailors rotated boards each race so each competitor sailed a different board in each race because there were more sailors than boards. A tight start line, a subtle ebb tidal current and slight wind shifts made for tactical sailing conditions for seasoned competitors and pleasant conditions for the beginner racers.

The mood of the event was casual and fun, no protests were made. A party barge anchored off the windward mark and stocked with “refreshments” provided front row seats and shade to sailors that were waiting for their next race, and friends and family to heckle at competitors on the racecourse.

Also known as the Dinosaur (DINO) Races because the sailors have maintained their Windsurfer One Design races and their original equipment; these enthusiasts have preserved the fun and social aspect of the Windsurfer One Design Class events of the 1970s & 1980s. To read more about the original Windsurfer, visit www.originalwindsurfer.com

The 4th. Kona Gold Cup had winds from 4 to 40 knots, extremely competitive racing, a record number of 86 competitors from 11 countries, great parties and a fantastic organization – both on and off the water. Additionally, and for the first time in the history of the class, – the Cadets (U14) was included with a separate start.
The Swedes demonstrated their superiority already from race one – with sailors of all age groups – from 15 year old Adam Holm, to 49 year old Hans Nystroem fighting for the podium positions.

As day 2 developed – with perfect conditions in winds between 8 and 15 knots – the veteran and ex Olympian Hans Nystroem had the day of his life with 4 impressive bullets, while the defending champion Bjorn Holm and his now “experienced” and super talented son Adam (15) climbed up to 2nd. and 3rd. after consistent sailing with several top 5 finishes.

Day 3 was a “fun day” dedicated to Long distance and slalom. It became a mega show for the big audience – with a spectacular beach start, and finish in the long distance race, and all the slalom heats organized close to the beach. Bjorn Holm “bagged” the long distance followed by Jurgen van Laarhoven (NED), Jan Pollack (GER) and Rainer Frohboese (GER) which gave Germany the team victory with the two best “country scores”. The long distance or alternatively Mahalo tandem races – traditionally counts like team fun races – but with adrenaline still flying high.:)

Day 4 arrived with sunny skies and winds gusting to 30 knots and more. Three more races and the slalom finals were scheduled, but the extreme conditions only allowed the organizers to run one course race in what will be remembered as the “survival race” – with no more than 6 competitors finishing in wind speeds gusting to 41 knots. Johan Ekstedt (SWE), Michael Rossmeier (AUT) and Mattias Petersson (SWE) displayed some “iron man” performances to finish top 3, and Johan Ekstedt continued to impress by winning the slalom finals ahead of Bjorn Holm and Helge Rotnes (NOR).

Hans Nystroem is the new Kona World Champion.
Still, the last race did not change anything in the top standings, and Hans Nystroem was crowned the 2009 over all Champion. Finishing “only” 6th. in the Swedish nationals six weeks earlier, it came as a surprise to many- but probably not to the man himself. His flawless and super focused performance must be credited his vast experience from several years with dinghy sailing and windsurfing at a very high level. Hans qualified for the 1984 Los Angeles Olympics and finished 10th. He then took up another challenge, and went for his second Olympic campaign – this time in the demanding Tornado class, but “only” managed to qualify as the Swedish reserve team at the 1988 Soul games.

Hans Nystroem;
“After a break from windsurfing for almost 23 years, Bjorn Holm called me up and told me about the new Kona concept, which I immediately thought was a super cool thing, so I jumped on it. However, I felt like a beginner again as I had never used a harness, footstraps or even a pivoting centerboard, but I am starting to get the hang of it, and have tons of fun thanks to the Kona Class.”

A big hand to the very worthy and extremely popular new Champion.

The 4th. Kona Gold Cup become a Swedish affair.
The Swedes harvested an amazing 18 out of the 22 medals available, including the top 3 over all, as well as in the women’s fleet. Karin Wendt (40) delivered a “shocking” performance and won all the races of day two – distancing herself from her competitors, and favorites like the defending champion, Kajsa Larsson and last years vice champion, Manuela Buch (GER). Like Hans Nystroem, Karin also had a break from windsurfing for almost 20 years.

Karin Wendt;
“It is fantastic to race in this class, because it is strategic rather than physical, so you just have to focus to avoid tactical mistakes. It’s great to be competitive once again, and this was definitely not my last race or championship.”

Show time with Ruben and Rossi
Among the competitors, we had the two freestyle gurus Ruben “Bang” Petrisie from Bonair and Michael “Rossi” Rossmeier from Austria – both adding to the extravaganza with Rossi entertaining the crowd with his incredible freestyle show – in 40 knots; don’t blink your eyes, and you will miss it sort of thing -

and Ruben turning a dinner party into a rap show no one will forget – performing a brand new “made in a hurry” song dedicated especially to the event. It had to be 3 dacapo’s to standing ovation from the enthusiastic “Konadians”. A man of all trades.

The man and his organization
A very special thanks goes to the event organizer Joachim Larsson, who administrated these championships – which can only be described as absolutely perfect – on and off the water. Joachim had hand picked his staff, which consisted of professional crews in all departments including the international judges, race officers, media staff, on-site catering and not to forget the event speaker Karl Magnus Soederstam reporting and entertaining from sunrise to sunset.
A memorable event, setting the standards for many more to come.

Tor Bakke
Kona Windsurfing Association

Article from kona-windsurfing.com

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Raceboard Designs

The IMCO was originally designed for a minimum wind strength of 15 knots (ie not really in displacement mode).  It was the best course-racing, high-wind (planning) design at the time of its creation (pre the wide tail revolution).  Even today in high winds (>20 knots), it is a very competitive design compared to the modern high volume raceboards.  The IMCO “works” in light winds, but it was never really designed for such conditions.

The IMCO offers great one-design course racing across the wind range, but its original mandate (>15 knots) and its dated design limits its application for heavyweights and delays the onset of planning.  A great board, but it needed to be replaced as the Olympic board, especially in today’s media / spectacle driven world, which gravitates towards fast planning action.

When Formula boards evolved, they offered spectacular planning racing (albeit a different type of racing to traditional IMCO/Raceboard racing) in relatively low winds (>8 knots), although they are not all-wind, real-world racing boards.  It was not surprising that the Olympics wanted to get a piece of this exciting action, although they needed a board for all conditions.  In the end they adopted the RSX, which is (in my view) a formula board with a centreboard.

The RSX’ attempt to bridge the gap between planning and displacement was skewed to the planning end of the spectrum to the massive compromise of displacement sailing.  The current proposed next Olympic designs are for even larger formula boards that can plane in ~6 knots, but these are still not all-wind real-world boards because they are pigs in displacement mode.

Displacement-focused designs, such as the Lechner and Serenity, offer outstanding performance in light winds.  However, they too are not all-wind real-world boards and do not offer the spectacular high wind performance of a planning design.

Raceboard designs after the IMCO (eg Pan-Am, Phantom) did not have the 15 knot minimum wind strength, and thus had high volume rails and tail, making them better all-wind boards and better suited to heavyweight sailors.  However, they are variations of the IMCO concept and have not yet (in my view) adopted some of the design insights of the wide-tail revolution of the past 10 years.  At the moment, I believe that they are the best available compromise between displacement and planning sailing.

The Dream Raceboard

The approach I’d like to see for future raceboard designs and future Olympic designs is to start with a true all-wind course racing board, then improve its planning abilities in lower wind strengths through wider tails and bigger rails.  In addition, I’d like to see a design that minimises the force required for transition from displacement mode to planning mode, following the lead of efficient skiff designs such as the 49er.

Reviewing some first principles of hull dynamics helps to understand the compromise that board designers face.  The illustrative diagrams below (adapted from “Higher Performance sailing” by Frank Bethwaite – highly recommended reading) show the relationship between board speed and drag for several different hull designs.

Some observations:

• The drag of displacement hulls is initially low, but rapidly increases with speed – at high speed, they are relatively slow and difficult to control

• The is a significant “hump” to the speed-drag curve for most raceboards – this reflects the effort required to move from displacement to planning mode (“getting onto the plane”)

• The 49er hull does not have this “hump” – there is no discontinuity between displacement and planning modes

The dream would be to have a “humpless” raceboard hull design like an 18 foot skiff or 49er.  The image below clearly shows the hull design of the 49er, incorporating a fine displacement-like bow and a broad flat planning stern.  This is the hull design that allows the remarkable “humpless” performance.

Given the light weight, small size and universal joint of a raceboard, a skiff-like design with a “humpless” drag curve may not be possible.  However, I believe that it is in this direction that future raceboard development should focus.

Prompting Progress

It appears difficult for manufacturers to justify investment into the raceboard class because the market is relatively small (albeit a fast growing segment).  In many ways, the raceboard community has recently been relying on competition between Star-Board and Mistral to progress raceboard design, but with the Equipe 3′s future in doubt, there may not be any incentive for Star-Board to invest in new designs.  However, the recent success of the Pan-Am at the world championships (beating the Phantom) may prompt further development.

Although the raceboard class is a development class, its rules are relatively restrictive and prohibit further development.  In particular, I believe that the thickness limit (which I understand was introduced to prevent the use of displacement hulls) and the production board registration requirements limit further development of the class.  The size restrictions on centreboards, fins and sails can also be considered to be deterrents to development.

As an ex-sailor of Moths and 18 Foot Skiffs, I appreciate the progressive environment created by few rules.  We used to joke that in 18s that there were (basically) 3 rules: maximum hull length was 18′; the race starts at 2pm; and the first across the line wins.  Moth rules were similarly simple.  It is no wonder that these classes led the most stunning developments in sailing design: apparent wind sailing; and foiling.

Although such free-wheeling rules prompt development, they come with a penalty: potentially higher cost and fewer participants.  The raceboard class can hardly afford to turn away participants.  However, Moths and 49ers (an 18 derivative) are now two of the fastest growing sailboat classes in the world – catering for the high performance segment of recreational sailing.

For Discussion

I don’t have the answers, but I’m interested in creating a discussion around the following questions:

• In what direction should raceboard design evolve, particularly in regard to the compromise between displacement and planning sailing?

• What should be the future of the Olympic sailboard class?

• What design direction would be in the best interest of the class?

• Should the raceboard class rules be changed to prompt further progress the class?

Share your thoughts.

The Author

Richard Reatti (AKA ‘yagon’) is an avid sailor of Raceboards at Dobroyd Aquatic Club in Sydney, Australia.  His sailing background includes extensive racing of skiff Moths and 18 foot skiffs, achieving top 5 places in their respective world championships and he was the world junior champion in the Moth class.  He is also a civil engineer specialising in fluid dynamics.