WINDYAK

Some answers to most frequently asked questions.

I don’t understand how beam and rig are not in the way of hands and paddle, when paddling ?

The chosen configuration is to have them low and close enough to the hips of the crew in order that they are not on the natural path of hands and paddle, as soon as you paddle with arms quite outstretched, using long size paddles designed for sea kayak.

In practice:

• On current available 5.9m boat, spars are placed very close to the paddler’s body and quite high above the water (the free board of the hull remains significant). Paddling is correct for adults, but not very convenient for children. We consequently will change the definition for our next products.
• For 5.05m boat (5.9m boat will evolve accordingly), mast & beam (and free-board) are now much lower, getting a two-level deck accomodation. Paddling comfort is significantly improved, particularly for small-size people
• For future 4.2m boat, mast & beam are very close to the paddler, and quite low to get a good propulsion ergonomics
• There is no difficulty with sea kayak kit, when you don’t paddle too close to the boat side. An optimised kayak deck shape for beam and mast accomodation would allow to even improve accomodation..

Is beam unfolding on water easy to perform ?

• On current 5.9m, beam is a bit too close to the paddler, what is not convenient when the skipper lifts it to get it above his head. Manoeuvre requires at the moment a bit of training to be performed correctly.
• For 5.05m boat (5.9m boat will evolve in the same way), the beam has been moved a little aside, and central beam support volume is enlarged accordingly. The goal is to get the beam leaning on it much sooner during its rotation, to allow the paddler to slip below it in a more ergonomic manner
• For 4.2m and sea kayak kit, this question does not exist because there is only one person on board for folding/unfolding, and there is no interference between the beam’s trajectory and the paddler. Beam rotates to the aft for 4.2 m boat and to the fore for sea kayak kit.

Doesn’t friction between the various parts during unfolding damage the boat’s skin ?

Experience got on current boat allow us to propose a suited solution.

For composite material made hybrid boats:

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  • PVC hatches are mounted at contact locations, fore and aft, between beam/floats in folded configuration, and main hull.

  • The geometry of central beam support volume is being modified to be able to cover edges submitted to abrasion by standard profiles.

• For kayak kit, a reduced local friction may occur on kayak deck at contact with float rotation axles; you may then protect the coating by tape.

• Beam is made of aluminium needing no special care regarding friction issue.

Is float’s unfolding hampered by contact between its transom and water surface when rotating ?

• There is no difficulty to unfold the first float.
• For 2^nd float, it can be necessary to heel the boat on the other side (already unfolded 1^st float) to have enough height between beam and water. This allows the float to move effortless.

When sailing, reduced volume of the float seems to be dangerous (capsizing) and speed limiting ?

• Stability is also brought by breadth, far larger than catamaran’s one. The free rig (without shrouds) acts as a safety valve to absorb smoothly the gusts.
• WINDYAK is not a pure performance craft but a concept offering the largest possible easiness with good fun. Nevertheless, thanks to its limited wetted area and weight, speed got is satisfying ( good power to drag ratio). Best performances close to the wind are logically obtained when using the righting moment of the crew (one people seat on the beam), to nearly only sail with central hull in water (this to avoid the relative high drag of short float at high speed) .

How to right after capsizing ?

We have not yet succeeding in capsizing… Waterproof mast avoids a full 180° capsize. The limited volume of the float eases righting. If necessary it will be possible to fill momentarily one of the float using its emptying hole to sink it with the help of the weight of one of the crew member. Some buoyancy still remains in the float to avoid, once the boat righted, to have the float sinking again due to its own weight.

Isn’t rig unfolding on water a bit tricky ?

It is not planned to unfold on water in 5 Beaufort scale number windy conditions…

Our design choice is to have a mast as long as the hull to get look and behaviour of a true light sailing boat. This requires, once beam deployed, to move back the mast to be able to lift the mast foot over the beam before locking it on the deck into a windsurf like joint. The technical solution ‘ jointed mast at step + partners’ is for us the most practical to unfold the rig on water, compared to just embedding a 5 or 6 meters length mast through a deck hole. The spar will indeed have, when carrying an -even perfectly- furled sail, a significant wind drag forbidding to right it safely. We have also avoided to use shrouds, with regards to the leisure sailing/paddling program foreseen for the boat: our goal is to get the « clearest » deck configuration as possible, by reducing the number of ropes on-board. The use of a furling sleeve is thus a big ‘plus’ to content the folded sail. Its handling is quite basic

For sea kayak, handling remains easily possible even in harder conditions thanks to rig reduced size and mass (total 3 kg)..

Note : The current partners system may be improved to be replaced by a foldable bipod, accomodated on fore deck (it is at the moment stowed when paddling on rear deck and must so be moved to the fore for mounting. That is what is currently done for sea kayaks, with the additional advantage of not having to modify the kayak to fix the mast.

How do WINDYAKs beat ?

• For large models WINDYAK 5.9m & 5.05m, the centreboard allows to beat just as a usual dinghyi
• For small model WINDYAK 4.2m, we have decided for simplification to remove the centreboard and to ensure anti-drifting by using small fins attached to the bottom of the floats, for expected sufficient performances.
• For kayak kit (the kayak is not equipped with a centreboard), fins on floats have been removed after some testing on first prototype; this, for wind drag, stability, aesthetics and not proven efficiency reasons. Float’ shape (vertical side) allows itself to provide some anti-drifting resistance. Paddle may also be used as an additional anti-drifting area, for non rudder-equipped kayaks. Although is shows quite significant drifting, the boat succeeds in going windward . To improve performance, we currently develop a lateral rotating fin fastened, as the central module, on the kayak inserts without requiring any modification.

What about WINDYAK sail balance ?

• For 5.9m model, deck layout constraints for two paddlers have forced us to move the centreboard to the fore of fore cockpit. The boat wants to go windward, but the rudder placed at the rear tip of the hull, and a long tiller, permit a fine steering, ‘with only two fingers’.

• For the sea kayak, using a non rudder-equipped boat, balance is now good (since mast was moved to the fore).