A Class Catamarans – A Look at the State of the Art Part 3

With reference to the illustrations, I will attempt to roughly cover the progression to angled and then curved foils.
Let’s start with a conventional centerboard dinghy.
On any point of sailing except dead downwind, the sail force will have a component across the boat. This is the aerodynamic sideforce.
For the boat to sail at a constant speed, all forces must cancel out as any net difference will result in some acceleration.
The forward component of sail force is balanced by hydrodynamic drag from the parts of the boat in the water (and some aerodynamic drag of the superstructure).

At rest we have sail drive force but no hydro drag. So the boat will accelerate.
As boatspeed increases, hydro drag increases. The boat will accelerate until the rising hydro drag equals the aero drive force. This will be the equilibrium speed.

Increasing the drive force and/or reducing drag will result in a higher equilibrium speed.
At the same time, sideforce is balanced by an equal and opposite hydrodynamic sideforce generated by the hull/board/rudder system, but principally by the centreboard/foil(s).
The hydro sideforce arises because the leeway component of boatspeed (arising due to sideforce) makes the water meet the foils with an angle of attack (AoA).

Since the aerodynamic force is generated above the water, and the hydrodynamic force below, there is a heeling moment that must be balanced by moving crew weight to windward.
But for now let’s concentrate on the forces as viewed from above.

Sail force and hydrodynamic reaction force can be broken down into components across the boat and parallel with the boat.
Note that a force can be thought of as the sum of any pair of components at right angles to each-other.
For example, components can be taken across and parallel with the
actual direction of motion (including leeway) or relative to the wind...

In order for the boat to be balanced in yaw (not want to luff up or bear away), the board must be positioned along the line of action of the sail force. As a boat gets wider, the board must therefore move forward. 
This, incidentally, is also why conventional monohull keelboats require the fin to be behind the mast if they are to remain balanced when heeled.

Simplified concept of the line of action of sail force and hydro reaction force.
As the board moves to leeward it must move forward.
In reality contributions to sideforce from rudder and hull must also be taken into account,
usually resulting in the board being even further forward.

The earliest use of angled foils that I am aware of is on the floats of ORMA 60 trimarans. 
When conventional upright foils were first placed on the floats to maintain side force when flying two hulls, they were naturally positioned forward of their counterpart on the main hull. 
The move forward was due to the wide platform beam and the windward cant of the rig. 
By some accounts (I heard it from Nigel Irens) it was noticed that when flying two hulls (and hence heeled significantly for a multihull), conventional upright foils tended to give a bow-up ‘assist’ that allowed the boat to be pushed harder.

Conventional upright foils give a vertical component when heeled.
If the mast does not cant, then this vertical component is canceled by the downward component of sail force that also arises with heel. If sheets are suddenly eased on a 'conventional' beach cat when heeled, the sail force goes away and the platform may momentarily 'jump' up as a result.

The next step was to angle the straight foils, but this resulted in an awkward exit angle with high interference/junction drag at the hull. 
So the next solution was to curve the foils such that they exited the hull vertically and became more horizontal toward the tips. 
A constant radius was the simplest solution since it allowed a snug fitting case without complex bearings, a significant factor for a large oceangoing boat.

Limiting factors are the hull exit angle and the tendency for the top of the foil to exceed any beam limit when the foil is raised. Also, the whole immersed part of the foil is displaced inboard. This reduces effective platform beam.

Note that a vertical component to the hydrodynamic reaction force produced by the foils exists even with straight boards. But it is small, and largely cancelled out by the downward component of the sail force due to heel (unless the mast cants to windward).

Once the bow up ‘help’ of angled and curved foils was noted, it became a logical progression to increase this contribution so boats could be pushed harder. 

In my opinion this has been a separate evolution to ongoing attempts at hydrofoil sailing where the aim was to actually sail the boat with the hulls completely out of the water, replacing displacement with hydrodynamic lift. 
That evolution had different priorities and came up with fundamentally different configurations.
Without delving too deep into this esoteric world, true foiling multihulls tended to use ‘ladder’ foils with no regard for beam limits and no hope of being competitive at sub-foiling speeds.

Experiments in 'pure' hydrofoil boats:
Specialist solutions included 'ladder' foils designed so that the total lifting surface
becomes smaller with increasing ride height and speed. Image source: www.foils.org

‘Hydroptere’ style angled foils bear a superficial resemblance to angled foils on displacement boats, but the physics are different.
To allow hydrofoiling, they work against each-other, the windward one providing half the sideforce plus some downward pull while the leeward one contributes the remaining half of the sideforce plus the necessary upward lift. For takeoff, the windward foil may actually be pulling up and to leeward. This is necessary when sideforce is too small to give sufficient vertical component to support all the displacement.

This configuration uses very large foils, spaced far apart, to achieve takeoff, with a large drag penalty at lower speeds.
The drawbacks would be crippling to time around a windward/leeward course.
A boat with a 'pure foiling' configuration of this kind would stand no chance in anything but fresh reaching conditions.
The vast majority of the time, a slender displacement hull has less drag than a true foiling configuration when averaged around a windward/leeward course.

Here the lee foil provides upward force and some side force.
The windward foil provides the rest of the sideforce and pulls down.
But for takeoff the windward foil may be configured to pull up and to leeward, with an associated induced drag penalty.
Note the extremely wide beam, surface interference, and spray.
This 'pure hydrofoiling' configuration evolved for specialised applications.
Image source: www.adriaan.com

Pure hydrofoil machines have tended to specialise in high speed straight line applications, falling outside established class rules. 
The Moth really brought full foiling to the racecourse within a 'box' rule. We will be looked later at the special circumstances that made this possible.

On the other hand, conventional multihulls to the ORMA 60 rule were foil assisted, using foils to help keep the bow up in hard reaching conditions. 
Angling or curving a foil that was already necessary to provide sideforce meant that very little drag penalty was incurred in more moderate conditions. 
This is very important because boats that have to race within a class around a course in varied conditions cannot afford to specialise. They cannot carry around additional foils (or extra foil area) only of use in some conditions on some points of sailing.

In the next post we will look at why outright foiling does not yet pay on an A cat that has to race on upwind/downwind courses in varied conditions…

A Class Catamarans – A Look at the State of the Art Part 2

   Understanding hull cross section shape independent of foils

In the following discussion we will look at the principles influencing cross section shape. 

As mentioned in Part 1, the extremely high length to beam (slenderness) ratio of each A Cat hull reduces the relative importance of wavemaking drag as a component of total drag. This is equivalent to saying that friction drag due to wetted surface is more dominant. 
In very simple terms, the hulls are so long and skinny that they push very little water out of the way for their weight. So friction due to wetted area accounts for more of the total drag than on less slender types.

Ideal underwater cross-sectional shape would therefore be a semicircle because it gives the least wetted area for a given volume. 
Strictly speaking, a semicircle gives the shortest perimeter to the cross section, the cross section being a two dimensional shape.

Think of the units:
Waterline Beam (m) X Depth (m) = Area (m²)

Area (m²) X Waterline Length (m) X Prismatic Coefficient (dimensionless coefficient) = Volume Displacement (m³)

Underwater cross section shown in red. Waterplane in blue.
The perimeter of the cross section is the edge of a slice through the surface of the hull at any given longitudinal location.
Think of a string placed on the hull along the edge of the cross section.
For a given volume, a semicircular cross section will give the shortest string.
When multiplied out by length, that gives the smallest wetted area.
The width of the cross section at the waterline determines the waterplane area.
In this diagram the cross section is approximately semicircular (twice as wide as it is deep).
A given cross-sectional area can be obtained with a range of shapes.

   Trends

The generation of boats immediately before the current one tended to semicircular sections but the latest boats have moved to more rectangular sections. 

On the face of it this is counter intuitive, but it makes sense when viewed together with the fact that overall volume has been increasing. 

As rigs have developed and sailing technique has improved, boats are spending more time on one hull. 

It follows that hulls are being optimised for taking more of the total displacement. 

Waterplane area influences the amount of ‘sink’ required to go from 50% displacement (upright) to 100% (flying a hull). 

Since length is constant, waterplane area in this context can be thought of as proportional to waterline beam. 
Wider hulls have more waterplane area so sink less for a given increase in displacement.

The amount of ‘sink’ affects:

- The ultimate waterline beam to hull depth ratio (remember that the ideal for minimum wetted area would be two to one).

- The amount of additional wetted area of the leeward hull at 100% displacement.

- The amount of heel required for the windward hull to clear the water. 
Roughly speaking, less ‘sink’ means less heel to fly a hull.
Less heel means earlier hull flying with more righting momenta and a smaller vertical component to the sail force since the rig stays more vertical.

Previous generation: waterplane area does not increase with sink,
beam to depth ratio departs from ideal as displacement approaches 100% .
The bits of flat vertical side panel that sink into the water
account for significant additional wetted area

In the absence of foils, the ideal hull shape would have a semicircular cross section with the centre of the semicircle somewhat above the upright waterline and near the 100% displacement waterline.
It would be wider than the previous generation of boats since the ideal semicircle is bigger - it needs to be because it has to displace more volume without sinking as far.

Ideally the waterline beam at 100% displacement would be exactly twice the hull draught and the cross section would be a semicircle.
This shape would minimise ‘sink’ by virtue of its increasing waterline beam (and therefore waterplane) with sink, keeping wetted area down to a minimum through the displacement range.

Current generation (exaggerated for illustrative purposes):
larger waterplane, less sink, significant wetted area penalty

The latest A Cat hulls have a wide waterplane and large overall volume to minimise 'sink'. However, they depart significantly from the minimum wetted area ideal.
Departing from the ideal minimum wetted area shape can be justified in terms of other factors. For instance, if the waterline beam to hull drought ratio is constrained at two to one, the rocker depth is effectively 'pegged' to waterline beam. Due to dynamic factors, it may be better to flatten somewhat the bottom of the cross section, reducing rocker at a small cost in wetted area.

The current trend deviates significantly from the minimum wetted area ideal by being wide, very flat, and having a hard turn of the bilge.
This is often attributed to the prevalent foil setup.

To understand the influence of angled and curved foils, we need to look first at their basic principles and then at history. Part 3 is coming soon…

Theoretical ideal for minimum wetted area:
wider than older generation, increasing waterplane with sink,
semicircular cross section at full displacement

   A technical point regarding comparing like with like

Note that making the ends of the boat fuller will reduce the cross section area for a given displacement. However the merits of different cross section shapes remain valid when comparing hulls with similar total volume (displacement) and fore/aft volume distribution. 

The expression for the fullness of the ends is the Prismatic Coefficient (Cp). 
Cp can be thought of as simply the ratio of the actual volume of the hull to that of an imaginary prism of the same length with a cross section equal to the largest cross section of the hull. 

Cp = Actual Volume / (Midsection Area X Length)

A barge with untapered ends would have a Cp of 1 since actual volume would be the same as the theoretical prism defined by cross section X length. 

Sailboats usually have a decimal Cp since they have tapered ends.

To understand the effect of Cp on total volume, imagine increasing Cp by simply making the ends fuller.

Since

Cross sectional Area X Waterline Length X Cp = Volume,

if Cp increases then cross sectional area must decrease to keep volume constant.

Think of it too in terms of the units

Area (m²) X Length (m) X Cp (dimensionless coefficient) = Volume (m³)
Volume in turn has to be equivalent to a mass of water weighing the same as the boat. 
Hence the interchangeability of the terms 'weight' and 'displacement'.

Increasing the Cp and keeping volume constant effectively requires taking volume out of the middle and putting it in the ends. 
In this discussion we are concerned with the effect of cross section shape for a given cross section area. Meaning the same area distributed differently within the cross section shape.
The conclusions remain valid for different shapes at any given cross sectional area.

For those of you who are interested, there is a detailed explanation of Cp on our press/articles page.

A Class Catamarans – A Look at the State of the Art Part 1

   Key dimensions

   
Length: 5.49m (18’)

Beam: 2.3m (7’ 6½”)

Weight fully rigged: 75Kg (165lb)

Sail area: 13.94m² (150ft²)

Crew: One person

   Rig and power management

Though relatively narrow for a catamaran, righting moment is good thanks to the skipper being on trapeze. 

The wide staying base and lack of a jib (no need for great forestay tension) result in low stay tension/mast compression. This allows the use of streamlined masts that rotate about the vertical axis, reducing aerodynamic drag and increasing sail efficiency. 

Masts have evolved to interact with the fully battened square top sails in sophisticated ways: Fibre distribution in the carbon spar is tuned to optimise bend properties with these interactions in mind.
The current generation of masts is more flexible across the long (fore/aft) axis than in the short (port/starboard) axis of the cross-section.
They can be set up to flex significantly under mainsheet and downhaul (cunningham) tension going upwind, when the long/soft axis is closely aligned with the centreline of the boat.
Downwind, when the mast is rotated approaching 90 degrees (so the long/soft axis is across the boat), and mainsheet and downhaul tension are less, the mast remains straighter, making the sail deeper.
The deeper sail allows an increased lift coefficient. This is important for downwind sailing since sail area cannot be increased. 

In other words, the upwind/downwind transition involves altering the lift coefficient of the rig rather than the sail area. 

In contrast to boats where additional sail area can be hoisted downwind, the A cat single sail rig must be very versatile. 

The mast bend characteristics are also tuned to automatically depower the sail by ‘spilling’ the square top and opening up the leech from the top down at maximum righting moment. 

The flexibility of the mast can be tailored to the weight of the sailor to optimise the point at which automatic depowering occurs.
Automatic depowering is desirable because it reduces the workload on the skipper. 

Mast height is not constrained but consensus is around 9m.
One consideration is to raise the centre of effort (CE) sufficiently to induce enough heeling moment to fly a hull early in the wind range.

A cat rig ‘moded’ for height (upwind) or drive (downwind).

   Platform characteristics

The above key factors lead to a very efficient boat with some unique traits:

- The displacement to length ratio of each hull is orders of magnitude greater than most other classes.
- Hulls also have a very high length to beam ratio, so wavemaking resistance is less dominant and wetted area is important.
- The hulls have to work through a 100% increase in displacement (from taking half the weight of the boat when upright to supporting all the weight when sailing on one hull) over a wide range of boatspeeds.
- With advances in rigs and sailing technique, the boats are spending more and more time on one hull. One of the extremely rewarding challenges inherent in the class is learning to ‘do the wild thing’, sailing downwind on one hull.

- Since the weight of the crew is more than 50% of the total displacement, drastic changes in trim can be obtained by simply moving around on the boat. In strong winds, crew weight can be placed right at the back to resist bow down trimming moment. In light winds weight is moved forward to reduce transom immersion.
- Construction favours platform stiffness within the minimum weight. Beams are increasingly unsupported (strikerless) and bonded to the hulls.

   Trends

Hulls are trending to fuller and more ‘U’ shaped sections with greater maximum width, wider sterns and flatter bottoms.
This is often justified as being connected with angled and curved foils but much confusion exists regarding the physics involved.
It is therefore worthwhile to examine first the effects of hull shape and then the story of curved foils to fully understand the latest A cats.
Stay tuned for Part 2…

New A Class Catamaran by Carbonicboats – The Brief

In previous posts I expressed my motivation (why) and approach to new projects (how).
I stated the importance of clearly identifying the needs of the user, and talked about the effectiveness of working to a congruent brief.
These beliefs drive quality. They will be shared by all who value passion applied with focus to create things of beauty.

Now, on the practical side, here are the goals defining the new boat:

Fast around the course

Best time on a typical windward/return race course. 
May sound obvious at first, but this requirement is vital to exclude any specialist or extreme solutions. 
With reference to existing designs, we are investigating variables in hull form, foil geometry, aerodynamics, and structural arrangements, to identify the best compromises for winning races.

Controllable, simple, responsive to changes in trim
The boat must react positively, taking advantage of movements in crew weight. This is related to volume distribution and rocker profile.
The boat must be dynamically stable in pitch, overcoming a critical limit on existing boats. By addressing the pitch stability issue inherent in existing boats, the skipper will be able to push harder with greater safety.

Optimised for the most frequent conditions whilst remaining competitive in light wind and controllable so it can be pushed hard in strong winds
Appropriate weighting should be placed on prevalent racing conditions, taking into account accompanying wave states. 
Having made primary gains in the target conditions, we have identified secondary gains in light winds and in top end conditions to remain competitive at all times.

Crew weight
Account for a crew weight of 85Kg dressed. This allows enough volume for average-to-heavy sailors to be fast. 
One of the constraints on the hull shape is a tolerance for a range of crew weights.

Platform stiffness

Global stiffness is a high priority for two reasons: maintaining the design geometry (correct angles between rudders, boards and rig), and minimising energy losses.

Durable and easy to repair
Material selection should take into account toughness, durability, and ease of repair. 
Given the class minimum weight rule, the available mass should be distributed to satisfy the requirement for stiffness, but also to safeguard the longevity of the boat, thus protecting the investment of the buyer.
Under this requirement, future-proofing for foreseeable foil developments and rule changes is vital. The boat should be easily retrofitted with future generations of foils with minimal modifications. Obviously we cannot foresee all eventualities, but we should make allowances for reasonable variation.

Cost competitive

Best performance/cost relationship, achieved by investing in well thought out tooling, and optimising the production process. 
Solutions will be ranked according to performance criticality, so that their cost can be factored in accordingly.

Able to take existing rigs, but with provision to accommodate longer chord masts

It is common practice in the class for skippers to carry over a ‘personalised’ rig from platform to platform. We aim to allow this on the new boat by maintaining consistent the geometry of stay attachment points, mast step, and traveler location. However we envisage investigating different rig solutions in the future.

Emphasis on reducing platform drag

We have identified possible gains in crossbeam, trampoline, and deck solutions that will be investigated during the design and prototyping process.

Aesthetically pleasing and well detailed
The boat must reflect our core values expressing them in the overall shape and in the detailing. 
Styling should be elegant and use a consistent formal language. 
The boat should have an integrated, unitary look.  
Quality should be reflected in a pained finish to a custom boat standard.

New A Class Catamaran by Carbonicboats – Why

   Clarity in belief and intent

This post is a personal reflection on why I do what I do, sparked on the occasion of taking on a new challenge. 

Why we take on a project is driven by our values and beliefs. 
I value quality in design and execution because it makes the user experience satisfying. 

I believe that quality results from passion applied to fulfill a need identified in a community. 
Passion motivates us to go beyond the ordinary.
Understanding the need, preferably through firsthand knowledge, guides us in truly improving the user experience. 

These values are embodied in the things we create, and shared by those who use them.

   Some personal background

Following is a personal account of why good design came to be a core value for me. And why I work to improve the experience of others through quality products. In ergonomics, durability, value for money, styling and engineering, quality is inherently valuable as it brings pleasure to the user and the beholder.

I discovered sailing quite by chance when very young. The beauty of a machine extracting energy from the wind fascinated me deeply. 

Growing up in Milan, I was fortunate to pass summers at the sea or lake, where I could access sailing clubs, tinker with boats, and actually go sailing.

I discovered a community of enthusiasts, people equally smitten with my obsession. I found that the exchange of learning in this community can be deeply fulfilling and forge lifelong friendships.

I was again fortunate to live in Sydney from my early teens. Here I could sail many boat types, through all seasons. I was also learning the theory, consuming books such as The Symmetry of Sailing and Principles of Yacht Design, as well as experimenting with models - something accessible, practical and of profound didactic value.

By the time I was in university I had discovered the satisfaction of offering to my fellow sailors improved technical solutions. I also learned the value of collaboration with the right people in each discipline, using teamwork to go beyond the capabilities of each individual. Always seeking out excellence. I began to think in terms of the whole project, coordinating different specialists to get the best outcome.

Persistence reinforced my belief that any solution can be improved to be lighter, more efficient, more user friendly, and better value for money in a cyclical process of expression, learning from the work of others, and implementing the next step to advance the state of the art.

Knowledge of fluid dynamics and composite structures led me to discover aviation, a kindred discipline. Aircraft and sailboats, occasionally automotive aerodynamics, all became part of my interests and skill set.

I relished disciplines where efficiency is rewarded and the winner is the first to finish.
I pushed to get involved, to contribute, to lead. From hands-on work, to design, to fundraising, I tried my hand wherever there was a chance to create something beautiful.

With maturity came understanding of the trade-offs favoured by different rules, something I have published on extensively. 
My break came when the America’s Cup was in Auckland and I knocked on every door to get the chance to prove myself. 
The roles I readily fell into were often concerned with production and management, a shift to an approach broader than strictly design.

As my passion became my livelihood, and I worked in different industries, I learned the importance of considering economic and market factors as integral to the design brief. 
Clients know that my approach puts a premium on listening to the brief and providing the best solution both technically and in terms of value for money.

   Full immersion before taking on the development of a new product

When deciding to take on a project - once the crucial ‘sine qua non’ of it being an engaging technical challenge has been met - I always do careful research to understand the ‘scene’ and potential customers. 
When developing items for production, I spend time to really understand firsthand the state of the art and determine whether a gap exists for an alternative in line with the core values of Carbonicboats. 
This was the case in Marbleheads, then One Metres and recently in A Class catamarans.
It was definitely the case with our UAV/drone work: I will only allow the company to take on a project if a clear opportunity exists to really move things forward. To reinvent a category for the better.

A valid point of difference must be identified that is consistent with the drive to improve design and offer better performance at enhanced value for money.

   The A Class Catamaran

‘A Cats’ are a development class, with restricted length, beam, displacement, and sail area. 
There is a premium on efficiency: one must make the most of a given ‘power plant’, since sail force and righting moment are constrained.

The exact needs of this prolific and welcoming class were crystallised in my view having taken on the challenge of learning to sail and race an A Cat.
I now believe there are several factors that, combined, point to a clear opportunity to take the next step in terms of performance, design, quality and value for money.
These factors broadly come under:

-          The current state of the art in hull and, particularly, foil technology

-          Geographic considerations in how the market is currently serviced

-          Renewed interest due to the ascent of multihulls generally.

The bar is very high as the leading products available right now are excellent in terms of quality and refinement. However it appears that limits are being approached in the concept driving the configuration of the platform. An improved solution would be well received.

For this project Carbonicboats is collaborating conditionally with a proven and well known multihull design specialist on certain concepts to be tested. The name will be announced shortly.

   Conclusion - to make the experience of sailing feel right through a product that is a joy to own

Why take on this project? I want fellow sailors to have access to a high quality competitive boat that is easy to control when pushing hard, responsive in all conditions, long lasting, and beautiful. 
I believe that our approach, defined by clarity in why we are doing it, guided by a robust brief, driven by passion, and aided by powerful tools, will generate a high quality boat that makes sense and feels right.

Octave Marblehead

Here are some pics of the final shape, incorporating the changes described in previous posts...

Musings on Exploring the Design Space

I have often made the point that rules are as much a driver in the development of racing sailboats as any other factor. 

Access to manufacturing technology, knowledge of materials, power of computation, the accumulation of empirical knowledge, fashion, and the evolution of athletic technique all catalyse within the boundaries of the design space* as defined in the wording of class rules.

The rules act as a lens to both sharpen and distort the theoretical optimum tradeoffs. 

This is often lamented as an undesirable constraint placed on the creativity of the designer, but, on analysis, it is both inevitable and inextricably linked with progress.

On some level every technical challenge is defined by its constraints. In fields such as civil engineering these might typically be budget, available resources, time frame, and physical boundaries such as geological features, existing infrastructure, or private property limits. 
In the aeronautical world the brief may be bounded by a power source, required range, payload, runway length, and similar hard parameters, as well as client preferences.

In sport the constraints are necessarily arbitrary. In football (soccer) there is a stipulated prohibition on players using their hands to advance the ball. In motorsport, each category places limits on engine capacity, fuel potency, aspiration mechanism, chassis dimensions, aerodynamics and any number of other factors.

Quite apart from necessary safety aspects, some of these rules may exist to limit costs, but ultimately they can be traced to a common need to artificially constrain the terms of the game. This means closing off parts of the design space that could lead those who venture there either to a runaway win or down expensive blind alleys.

Competition does the rest. At times, holes in the boundaries of the design space need to be mended as competitors throw resources at methodically testing the edges as defined in the wording of the rules. 
The pressure of competition pushes to uncover newly advantageous points in the space.

Patches, however, can only be implemented periodically, as it is vital that rule validity and immutability be tied to a known time horizon.

Typically this cycle involves some form and degree of ‘arms race’ that depends on the length of the competition cycle, the resources brought to bear, and the effectiveness of the wording of the regulations.

In every case the absolute key to the survival of a game is the ‘knowability’ of the rules. 

Specifically, the knowability of the method used to interpret them, and the period of their validity in their current version. 
If the impartial validity of the rules is in question, it will not make sense to invest in exploring them, designing to them, and ultimately taking part in the game under them. 

The risk of the ‘goalposts being moved’ once one is committed, would make any serious effort to take part with a view to winning a waste of time and money.

These universal principles have given rise to institutions and procedures developed specifically to administer sports in order to strike a balance between the need to crowd the design space to keep competition interesting and the periodic mending of holes in the boundaries of said design space. 
As with complex systems such as economies, knowability is vital for stability and success.

The interpretation of rules involves a hierarchy that ensures constructions (as in 'to construe') will be ranked in a reliably predictable order that everyone will agree on (agree, that is, on the order of interpretative methods, not the outcome). 
Namely, the plain text or literal meaning always takes precedence. 
Only in the case of ambiguity or patent absurdity does intent come into play. 
This makes sense because the plain literal meaning is far more dependably repeatable than conjecture about the mind of whoever drafted the rule, whether they are still around or not.

There is real beauty and value in the elegance of a rule and the attendant machinery for its interpretation and maintenance. 
It is rules that focus minds, channeling competitive drives into targeted refinement that can be quantified by simply looking at the finishing order.

After all, if the brief were simply “get from point A to point B before the other guy”, the best solution could be a powerboat, a plane, or a jetski, depending on the length of the course. 

Even in such an absurdly simple case, boundaries would have to be identified in order to be able to make any meaningful attempt at preparation. 
Things like the course distance, budget, and what the other competitors are doing, would all be used to formulate an analogue to a rule in which to work. 

Even in the case of such an open challenge, one often hears that ‘the size of the shed’, human muscle power, the previous benchmark to beat, or other such constraints were identified at the initial design stage. 
In any case, point A and point B are arbitrary constraints to begin with, and participation in sports is voluntary - albeit occasionally representative of real life challenges and rivalries such as competition between nations for trade routes or proficiency in technology that may have applications in defense.

In other words, like snow crystals that develop into exquisite forms after beginning the process on an airborne particle, the development process needs some starting point and some references to get going. 
The best results come when an open free space is clearly defined by a goal and edge boundaries. This is true in the development of products, businesses and racing vehicles.

Planned economies, where an enlightened elite arbitrarily permits certain things and bans others, have consistently failed. Even if the rulers act in good faith, the outcomes are both distorted and demotivating to wood-be competitors.
Societies where rules are clearly defined and consistently applied give rise through real progress through competition and collaboration.

At the risk of delving too deep into philosophical niceties, I want to share this fascination with the mechanism that forges the expressions of our creativity. 

By happy accident, good class rules gave us the elegance of the IACC boats, the power of IMOCA 60s, the efficiency of Marbleheads, and the sheer speed of the development skiff classes. 

The open wheel tradition of F1, through countless cycles of radical innovation and corresponding tightening of the design space, generated the look that we associate with fast racing cars today. 

Similarly, the ‘happy accident’ of the monohull constraint gave us the ‘T foil’ Moth that, combined with heel to windward, spawned a genuinely new way to resolve the major forces in a sailboat.

In all cases, rules with a known time horizon of applicability and a reliable method of interpretation were instrumental. 

Always scrutinised by those interested in maximizing performance, and always construed in the knowable hierarchy: literally first and foremost.

Creativity excels thanks to the structure provided by rules. 

There is something beautiful and exhilarating in an elegant solution that discovers a new point within a space bound by wording that was penned by another - Another whose intent could not foresee that particular point in the space being originally defined. 

And that is how it should be since nobody today can predict the progressive solutions that competitors will invent in the future. So all we can do today is define the space and let future minds play in it, then marvel at the new places they will discover.

_______________________________________________________________________

* Think of the design space as all points on a graph that lie between axis representing the parametres controlled by a rule. 
In the case of a simple rule where length and sail area are mandated, there would be two axes. Sail area would be on one axis and length on the other. 
If permitted length were 10 to 10.5m, and sail area 20 to 25 m^2, the design space would be every point on the plain defined by the two axis between the values of 10 and 10.5m on the length axis and 20 to 25 m^2 on the sail area axis. 
If a hypothetical rule also controlled displacement, then the design space could be represented by adding a third axis orthogonal to the first two. 
Now the design space becomes three dimensional. 
The space would be bound by a prism with a cross section equal to the area defined by permitted length and sail area values, and a length equal to permitted displacement values.
A boat with dimensions equal to the middle values for the three permitted ranges would be said to be sitting in the middle of the design space. 
A boat with max length, max sail area and max displacement would be up against the edge of the design space. 
If more than three parametres are restricted by a rule, the rule space becomes an abstract multidimensional one.
But the principle remains the same: each boat that 'measures' in the rule corresponds to one point in relation to each of the measurement parametres.

IACC Rule Space - Image credit: Unknown

Octave Development Bearing Fruit

We now have comprehensive feedback on the Octave design.
Qualitative and quantitative tests have enabled us to evaluate the radical features incorporated into the prototypes in order to decide on values for future production boats.

More detailed explanations of the design choices will be published later, but the broad concept has been validated.
Overall beam, prismatic coefficient, the characteristic forward location of the centre of gravity, the piercing bow, and the chambered deck are all retained.
The treatment of the chines has been softened as the volume distribution is maintained, but the water-shedding characteristics of the chines were found to be detrimental in some conditions.

Overall volume has increased, as has the midships freeboard.
Some moderate hull flare has been introduced in the centre section to reduce sink at large heel angles, and the deck height at the mast has been increased to both increase heeling moment and keep the booms clear of the water in rough conditions...

Congratulations to Ray Joyce who won the day this past Sunday in light conditions with the much modified original Octave prototype.
Results courtesy of Ray and Ridson Brook Radio Yacht Club.

RISDON BROOK RADIO YACHT CLUB Inc.
INTERNATIONAL MARBLEHEAD RESULTS, Sunday 19th February, 2012
Rank	SailNo	HelmName	R1	R2	R3	R4	R5	R6	R7	R8	R9	R10	Total	Nett
1st	93	R Joyce	1	1	2	-4	2	1	-3	1	1	2	18	11
2nd	60	W Behrens	2	-3	1	1	1	2	2	3	-4	1	20	13
3rd	5	P Darcey	3	2	-6	2	4	-6	1	5	3	5	37	25
4th	67	A Furmage	4	-6	4	3	3	-5	5	2	2	4	38	27
5th	10	K Dobbie	7	4	3	7	5	4	6	4	5	3	48	34
6th	19	L Hanson	5	5	5	5	-6	3	4	-6	6	6	51	39

Congratulations to Michael Hickman

For a well earned third place at the Australian Championships sailing an Ajax by Carbonicboats.
Great to see that the M Class is alive and well, with a very high standard of sailors and equipment.
The Event Site can be found here

Not What it Said on the Box

I found the following interesting enough to post and comment on.

It is an open letter to the America’s Cup Event Authority (ACEA) by somebody who was associated with a credible prospective competitor. 
Given my experiences as part of an official competitor that found the ever changing new format untenable, I would broadly agree with the principal views expressed in the letter.

However, focusing as it does on the point person, is perhaps to the detriment of a broader look at an organisation that has great resources available, and an admirable stated vision, but appears to be working without defined milestones, and hence with no accountability/metrics for quantifying success with reference to its stated aims. 

The old saying of 'shoot first and call whatever you hit the target' comes to mind.

Analysing the shifting philosophies (such as the decoupling of the ACWS from the AC 'proper'), the stringent controls being stockpiled by the Defender, the inconsistent treatment of different competitors, and the ongoing redefinition of identified profit centres, one cannot help but speculate that at least some of the actions of the many branches of the organisation are governed by different and conflicting agendas. 

Add to the mix massive commercial interests without the checks and balances of a strong voice from challengers with genuine countervailing interests, and you have an event that resembles more a choreographed WWF wrestling show than a 'friendly competition between nations'.

If these were isolated outbursts of individual criticism, they could be dismissed as 'sour grapes' and we could all get on with the show. 
But the mounting evidence is pervasive and compelling. 
The credibility of the critics is growing, and the objective results are indicative of a deeply flawed approach if the stated goals are taken as a measure of success.

In my opinion the single best thing to come out of this low point in the cyclical nature of the AC is the rediscovery, popularisation, and acceleration in development of the modern racing multihull.

For this unwitting byproduct I am grateful, despite the mess.
The show will be spectacular, in a way similar to the Valencia DoG match: The boats will be spectacular. The images will be compelling because of the backdrop and the accessibility of the course. 
But, again, it will be low in numbers and be steered by a power that is not counterbalanced by genuine opposing interests.

"An Open Letter to America’s Cup Event Authority Chairman Richard Worth from 
Peter Huston

The purpose of this letter is to bring to your attention the concern that many of us share in the direction that you are taking the marketing aspects of the America’s Cup, and to offer suggestions for improvement.
I speak not as an individual; however I do have experience with ACEA as an individual through my association with Paul Henderson and Kevin Reed of Red Maple Racing, a life long association with the sport, and an experienced background in entertainment marketing, including sailing. Rather, I speak as someone who gets constantly asked by friends within the sailing community about what is up with the Cup. They want to place blame on Golden Gate YC for not reaching out to the sailing community and not telling the story of what’s up with the Cup. The blame is not GGYC’s, the blame is yours.
As much as you and the rest of the staff at ACEA might want to spin things, in addition to your failure to reach the sailing community, of those few people you have reached, you have alienated far too many, for no good reason. “Out with the Flintstones and in with the Facebook” was just the start. Many of us grew up with the Flintstones, and have a Facebook page. Announcing ACWS dates, but no venues, and then never fulfilling those dates, as recently as this January. Why have announced dates with no venues too often not materialized? Is it because you had completely unrealistic venue fee pricing expectations based your completely unrealistic and unsustainable event production budget? A checkered flag at the finish line? Seriously? In a day and age when “authentic” is a big buzz word, what is authentic about taking something that is a signature within motorsports and using it in sailing?
Obviously, the front page story in the San Francisco Chronicle Saturday morning said all that needed to be said about the overhype that ACEA has had about projected attendance figures for Cup events. Those of us in the game a year ago knew that ACEA was spouting utter nonsense with those attendance projections. No wonder the City is now giving ACEA very justifiable pushback.
But those are small problems in the scheme of things. Currently, Grant Dalton is screaming that the Cup is not any less expensive than in the past, and is in fact 20% more expensive. Grant is also citing the fact there are only three billionaires and his team currently entered in the 2013 America’s Cup. As a part of one of the teams who a year ago took a very hard look at entering the ACWS and the America’s Cup, I have a decent idea what the costs are, and while we can debate Grant’s statements, the bigger issue than costs is the abject lack of definable media expose for potential sponsors. A year ago ACEA had no real set schedule for ACWS events, and no real media schedule. During the last year, nothing much has changed, including your assumption that broadcasters are going to line up in a bidding war for TV rights. That is not going to happen, especially in the US. If you had signed major TV broadcast partners, you’d be talking about them. Instead, we got press releases about the chef in Cascais. If you had signed major broadcast partners, it is highly likely we’d have more than the current three challengers entered.
Many people think more teams aren’t announcing their entry into the ACWS or Cup because they can’t find sponsorship money. I don’t know about other teams, but I do know about Red Maple. A year ago the issue was not finding interested and willing sponsors, the issue was being able to assure those sponsors that ACEA, meaning YOU, would come through with ACWS venues and a major media schedule. Red Maple elected to not go forward because there was no evidence you were going to perform as would have been necessary to satisfy those sponsors. Those teams who did not go forward are probably relieved they did not. Those teams that are still in the game and are hanging on by their fingernails are still waiting with bated breath for the announcement of your ACWS venues and dates, and for the TV package to be announced.
Simply put, the teams who rely on sponsorship to make it to the starting line in 2013 will not be there unless you announce ACWS venues and dates and your TV distribution package within a couple of weeks. The sooner the better. It almost does not matter what the package is, it just matters that there is something concrete to point to. For the prospective teams to obtain sponsorship there MUST be a media schedule that is actually in place. The most bizarre part about all this is that you cited ESPN2 in the ACEA Media Footprint document which was circulated last year, yet you had not made a deal with ESPN. The single thing that you could do immediately to start to reverse the trend of negative publicity that is currently besieging the America’s Cup is to make a deal with ESPN, and announce it. YouTube is amusing and all, but ESPN brings to the table the credibility that you lack, and which the America’s Cup needs, right now. The group of people who are most likely to come to San Francisco in the greatest numbers for the Louis Vuitton Cup and America’s Cup are people from the US, particularly those who are lifelong fans of the America’s Cup. Why you have essentially ignored the US market is beyond our comprehension.
Sure, there will be an America’s Cup in 2013 in San Francisco. But instead of a grand spectacle, it will be a whimper if no more than three challengers show up. Three challengers is a race, but it is not a regatta, and it is certainly not much of a show.
Right now, because of ACEA’s abject failings Golden Gate YC and the America’s Cup have a very serious credibility problem, largely because you as the Chairman of ACEA, the marketing arm for the Cup, completely over hyped and constantly under delivered on virtually every single thing you set out to do. So, the question is now: Are you just like ‘Captain Coward’ Francesco Schettino of the sunken Italian luxury cruise ship Costa Concordia, seeking refuge in a life raft that is just another ACEA spin city press release? Or, are you man enough to step up to the helm in the storm that you have driven the America’s Cup into as a result of your poor tactics, do the right thing for the Cup and the sport, and finally make some media and venue deals that sponsors can rely on so that they can agree to support teams who want to enter the 2013 America’s Cup? 

- Peter Huston." 

Carbonicboats Collaborates with Kedo

Here are some preview images of the Kedo range of carbon fibre houseware and furniture.
These creations are made using a proprietary technique that gives the best features of glassware, with the unique aesthetics of carbon fibre.

You can buy Kedo products now in Australia and New Zealand only from Carbonicboats. 

Choose from the standard range or ask about custom items.

2012 John Cootes A Division Catamaran National Championships

A lot has been written about the recently concluded A Cat Australian Champs.

Not much to add here except to agree that it was a fantastic regatta and a great way to learn about these elegant and sophisticated boats.

The hosts were generous and hospitable, the race management was smooth and efficient and the competitors represented a broad cross-section of our sport, from professionals to passionate enthusiasts.
The weather ranged through the whole spectrum and the atmosphere was exciting, welcoming and family friendly.

Below is a selection of links to reports, pictures and videos.

We are looking forward to developing equipment to fulfill the needs of this market in the next years!

Reports on MySailing.com.au:
http://www.mysailing.com.au/news/sailing-s-rockstars-get-their-instruments-and-will-come-out-to-play-on-lake-macquarie
http://www.mysailing.com.au/news/business-as-usual-ashby-dominates-a-class-cats-invitation-race
http://www.mysailing.com.au/news/ashby-bundock-on-top-at-a-class-catamaran-nationals
http://www.mysailing.com.au/news/big-names-at-the-top-of-the-a-class-cat-leaderboard
http://www.mysailing.com.au/news/nathan-outteridge-takes-to-a-class-like-a-duck-to-water
http://www.mysailing.com.au/news/ashby-in-a-class-of-his-own-on-lake-macquarie
http://www.mysailing.com.au/news/ashby-secures-a-class-cats-with-a-day-to-spare

Pictures:
http://www.a-cat.org.au/2012-nationals/sail-world-photo-gallery-for-the-2012-nationals/
http://www.flickr.com/photos/73409289@N05

Some videos:
http://www.youtube.com/watch?v=lT_m8S7WfnU
http://www.youtube.com/watch?v=hovL91SoN6Y
http://www.youtube.com/watch?v=Pa24YlmEP0k

Official host club website:
http://www.wangirslasc.yachting.org.au/

These shots from 'Bad Dog' http://www.flickr.com/photos/73409289@N05

Rigging

A few days of boat preparation are an interesting opportunity to come up with solutions to some problems common to many boat types. As always the factors to consider are weight, reliability, durability, cost, and repeatability. Usually in that order.
Here are some images of what we came up with...

Trapeze lines: starting from the top, the 2.5 or 3mm Dyneema is spliced over a closed thimble. Both thimbles bear on a single shackle that connects them to the conventional hounds plate or T-ball ring.
There is a 200mm length of core as a chafe guard where the line may touch the stays and sail/batten.
Since the 'hounds' on a rotating A Cat mast are rather crowded, and occasionally the thimbles will interfere with each-other before lining up as load is applied, some stickyback aramid cloth is applied to the exposed line where it lies in the thimble.

Moving down, machined round aluminium thimbles are used at the bottom end for the lower splice and as stoppers for the T-handles. They also act as turning blocks for the lower strop that has a stopper ball at the bungee end...

Merry Christmas

Best wishes and thanks to our followers, customers, partners, suppliers and fellow sailors.

May 2012 bring fair winds, health and prosperity.

Carbonicboats at Sail Sydney

First outing for the new test platform after only a very light wind race out of Kurnell the previous Sunday.

Having a designer at the helm meant expectations were low: The goal was to get around the course cleanly and begin gathering data (rigged the boat with instruments at some key locations) for baseline values before the scheduled mods begin.

The atmosphere at the regatta was excellent. A well run, well supported event in a friendly setting with many sailors of all ages enjoying the sport at its best. As always many thanks to the organisers for making it all possible.

On the first day the breeze came in late but did eventually allow four races to be sailed in building conditions that reached 15 knots by the end of proceedings. The second day piped in touching 20 knots with some steep chop so the decision was made not to push things just yet.

It certainly seems that the small boat scene and the beach cat fleet in particular are alive and well. Fantastic news for the future of our sport and for the industry.

Photo courtesy Andrew Hawkins, Mainsheet Media