What's In A Rig, Wing Sail

What’s In A Rig? – Wingsail

By: Sailboat Rigs, Sailboats

What’s in a Rig Series # 8 – The Wingsail

Although wingsails or rigid wings have risen to the limelight in the contemporary sailing world with the America’s Cup now employing the technology across the board, they are in no way a brand new concept. A sail, after all, in its purest form is essentially a wing. So, through the decades, many designers, looking for optimum performance, have of course instituted rigid wings (just like that of an airplane). A notable example would be the so called Little America’s Cup, a long-standing catamaran contest based around the pursuit of pure speed.

The efficiency of a hard wing has never been in question. They sail upwind higher and reach faster. Their purity of engineering allows for maximum proficiency. When compared to a solid wing, a soft sail is full of hard to manage variables. The shape, components and accompanying systems are no match for a wingsail. In many ways, a conventional sailboat rig is fighting against itself to do what it’s meant to do. Shrouds and stays are battling to keep everything in place while a sailor adjusts control lines incessantly. It’s not perfect. However, the relative practicality is another issue. A very large unbending non-folding solid structure has its obvious drawbacks. How do you stow this thing when you’re done sailing and how do you reef it if the breeze starts blowing and, for the traditionalists, where’s the romance in a big airplane wing sticking up from the front of the boat?

Before we address those questions, let’s look at how this rig works. Using the America’s Cup boats as great examples, a wingsail itself is usually composed of two parts and the surrounding system is essentially three ingredients.

The sail has a forward and trailing element. The trailing element is like the flaps on an airplane wing and the angle between the two elements is called camber. Increasing the camber (angle) produces power. If the power becomes too much, which it often does, another control system comes into play that deals with “twist”. Twist allows the ability to depower the boat by twisting the wing so wind can spill off.

After camber and twist, the third major aspect of control on these quite simple wing setups is the mainsheet. Like a normal mainsheet, it lets the sail out, but unlike a soft sail, a rigid wing doesn’t power up downwind, which is why soft genoas are often part of the sailplan.

So, without argument wingsails are more efficient engines, but, as we stated, are not nearly as practical as soft sails. Are you sensing the idea of a hybrid coming around the bend? Yes, in fact, world renown cruising boat manufacturer Beneteau has been developing just such an innovation. They have a soft wingsail prototype installed on a production boat that blends the two concepts. It’s made of cloth so it can be broken down like a traditional scale but is, in every other way, a wingsail. It’s an unstayed mast with an airplane style wing that they say behaves very much like its rigid cousin.

So, lets revisit the particular questions we asked earlier and make sure we answered them. How is the wingsail reefed? By adjusting the aforementioned twist control, a wingsai is depowered, thereby reefed. How can this big wing thing be stowed? Well, with this hybrid idea, it’s lazy jacks and sail covers – we know how that works.

The last question is more difficult to answer…where’s the romance? The feeling, sounds and shape that soft sails embody date so far back into our collective history, it’s a bit heartbreaking to think they could possibly be replaced. There’s a certain humanity…a beauty and art involved in harnessing these inherent imperfections. We share this struggle and achievement with those who sailed before us. We have continually developed materials, hardware and better systems to get an edge, and are always happy when we succeed, but a radical refit, should it happen on a grand scale, is sort of jarring and sad.

Alas, this is the quandary of technology and advancement. Change bringth and taketh away. But don’t worry too much about it – in this modern day it seems 18-year old yellow, fading Dacron sails hung about on aging wires are still representing strong!

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