Welcome to the home of soft wingsails, sails of the future!

At the end of October 2012, after the Oracle Racing's disaster, I sent the following letter to the editors of several sailing magazines and forums. Those of the Sailing Anarchy and Scuttlebutt were brave enough to publish it, provoking angry responses by some Anarchists.

Here it goes:
"I've read and watched recent stories about the last AC72 monster cat capsize.
I've been following the America's Cup races for the last 20 years as well, and cannot recall a single accident of this type.

By definition, multihulls are much more stable vessels than monohulls - aren't they?

Yet, monohulls, though slower, do not capsize to this 'epidemiological' extent, and do not suffer in such material damage terms. Alarmingly, the AC boats capsizing has become notorious, but nobody has ever questioned the issue.
Even the 'Capsize club' has been established, with membership proudly offered to most of the AC45 teams. Even formidable Russel Coutts pierced the wing with his head first!

What's going on? Where are the designers' comments? Where did the 'investigative journalism' disappear?

I'll give you a clue: the rigid wingsails are too heavy. Naturally, rigid things are supposed to have certain weight, and in this case it is a bit over the limit. Can AC wingsails be lighter? No, they can't - if they are to be solid. Why they must be solid? Because, by today's definition, wingsails are of solid, rigid, fixed, hard nature. Only jibs, genoas, gennakers and spinnakers can be soft.

Why this is so? Nobody knows ... except some weird minds.

But if the AC wingsails were lighter - why not soft? - there would be no capsizes, risking lives and million dollar damages!

Are there soft wingsails? Of course there are. Because rigid wingsails are basically useless for any other sailing purpose except those short elite AC races, many people brainstormed the idea of having a sail shaped and performing like a wing, yet having features of conventional cloth sails - weight, price, ease of manufacturing and handling.

And I am just one of them.

On the other end are strong, well positioned guys, who adopted the old idea of a flapping solid wing, a concept limited by 2D thinking, lacking imagination and inventiveness.

This sick brainchild survived decades, protected by vested interests, stubbornness, closed mindedness, vanity...regardless of price somebody might pay for its apparent deficiencies.

Do you think something is going to change if an AC crew member dies in a future capsize, which is inevitable and pending?

No, nothing will change. But remember what I've just told you."

And it happened on May 9, 2013. A top sailor has died, leaving his family, friends and community devastated. We all know there are some risks involved in sailing, but those risks must be recognized and diligently reduced to minimum.

I've been questioning the issue of AC boats easy capsizing for a long time, in particular by addressing the wing weight and attacking the Rule 10.12:
The weight of the wing in wing measurement condition shall be not less than 1325 kg, and the center of gravity shall be not less than 17.000 m above the wing base plane.

Interestingly, the minimum CG height in AC72 Class Rule version 1.0 was set at 15.25m, and later, in version 1.1, increased to 17m. Were the rule makers providing more room for heavier wings, instead of minimizing the risk of capsize? What led them to arrive at these exact figures? Fine calculation, emulation, comparative analysis ... or actual measurement of a finished wing taken for granted?

The rig's weight and the CG height are among the most crucial parameters in sailing, and the basic principles behind them are taught at physics courses in elementary schools. Higher the values, higher the instability, right?

Surprisingly, the values in the Rule 10.12 have been limited from below, not from above. So, a wingsail weighing 1000 kg wouldn't fit the rule, but another, dangerously weighing 2000 kg, would fit it. Is this insane? Prudent risk avoidance at its best?

From an interview with Paul Cayard in November 2011, we can see that Artemis was concerned with the weight aloft from the beginning:

"But when you scale up to a wing 130 feet tall, how do you control the beast? The first Artemis wing is under construction in a special facility in Valencia, Spain, Cayard says, and to control the moving parts in that wing, "We have 38 hydraulic cylinders. We want to avoid running hydraulic piping to each of them, because that would be heavy, so we have electrovalves embedded in the wing to actuate the hydraulics. But if you had two wires, positive and negative, running to each electrovalve, your wing would look like a PG&E substation, and that's heavy too, so we use a CAN-bus [controlled area network] with far fewer wires. Still, it's incredibly complex."

How heavy was the Artemis wing finally - 1325kg or more? Or perhaps much more, still perfectly fitting the Rule? Ever heard of an old saying "Err on the side of caution"?!

Who is to blame for this apparent design flaw - Oracle, who, as the America's Cup holder, sets the ground rules for the next competition, Artemis that further 'improved' the wing, or all challengers who agreed to the rules?

The basic slotted fixed wing type was developed decades ago for the Little America's Cup (nowdays known as C-Class), and through several generations of Patient Ladies evolved into the version still in use. It is fairly light, say 0.5 lbs per sq ft or less than 2.5 kg per m2, and manages downwind, which is important since C-Class boats' only propulsion comes from it.

However, it should be noted that its 'slotted' section is highly imperfect, something impossible to find on any aircraft, particularly gliders whose model wings should be followed. Does this imperfection contribute to naming AC72s 'wild untamed beasts'?

Why this design had been chosen by the defender, when AC boats use Code Zeroes for downwind legs, and there are better wing sections for upwind legs? Because it's become an in-house design? Because there are no intellectual property rights on it, as opposed to patented soft wingsails? Because the Oracle team didn't have capacity to figure out their own more intelligent design?

Unfortunately, the construction of this wing implies that increasing its area almost tenfold increases its weight progessively, so its specific weight jumped from less than 2.5 kg per m2 to at least 5,2 kg per m2! Has anybody paid attention to it?

The Rule 10.12 must be revised!

This issue must be rectified at its root, and not by introducing 'buoyancy aids, body armor, crew locator devices, hands-free breathing apparatus and high visibility helmets'.

As can be seen, the AC rule was written with fairly tight constraints, limiting spendings and any substantial development by the challengers. Not exactly one-design, but pretty close to it, letting the design teams figure out small differences only.

Ironically, with this clumsy design and all the disasters, the competitors have been exposed to huge expenses of fixing damages, renting cranes and shipping containers, hiring additional crews etc.

It can often be heard that AC72 boats belong to the space age and technology. In a way, this is true - but space ships designed by the AC experts would obviously fall apart a couple hundred meters after launching...

The America's Cup is the world's heritage, not a private property - and this way the organizers are jeopardizing its future.