Foil Assist for Keelboats(Not DSS)-Kuka Light and others

Kuka Light is an awesome design by Doug Schickler. He has looked at curved "S" foils-similar to the ones used on the foiling AC boats for use on Kuka. See the pdf below for lots more info. Kuka-Light has used standard daggerboards(like some Open 60's) with the top of the board outboard so when heeled the board develops some vertical lift. For years boards like this had the top of the board inboard so they were vertical when heeled.
http://www.styacht.com/

Some comments about the boat:

Kuka-Light is a very different boat, a real prototype. Full Carbon Nomex autoclave hull, rotating mast, canting keel and a light displacement around 3,2 Tons. This with a very agressive hull shape (12,8 m of length by 4,6 m of beam). Add to this a full carbon keel blade, an innovative battery system and you understand that such a boat needs a time for developement and lots of small adjustments to develop its full potential.

Kuka-Light was put into water after a two year build time last spring. Since then we fixed a lot of small issues, like the deck plan, the software of the batteries management, the sails and we had also to learn how to sail the boat. Yes, to learn how to sail the boat as you have to sail this monohull like a multihull, it means that you will sail it always in appearant wind mode, never to low, never to high.

Thanks to the expertise of Mitch Booth we could make a lot of improvements in a quite short time. We have seen that due to its displacement Kuka-Light is very very sensitive to the weight position. This means that the crew has to move much more like in a dinghy or a light boat like Melges 24 than on a traditional monohull, but it is very easy to sail and very light on the rudder.

When the wind is over 25 knots the boat is quite wet, a bit like the Volvo 70. Lots of spray and lot of fun with quite high speed.

Upwind we are quite satisfied with the performance we see and we are constantly learning and improving also our reaching and downwind speed, adapting the sails, mast position and so on. I think that we still have more potential to improve our downwind speed, but we are already a very fast boat.

We sailed till now two races, the first one was Palermo-Montecarlo. 600 miles with verylight wind, quite a difficult race where we arrived third behind Esimit (former Alfa Romeo) and a Cookson 50 canting keeler. After we sailed a race in Sanremo (Trofeo Gavagnin) and Kuka-Loght won line honors and handicap, beating a 60 foot canting keeler.

Next race will be the Middle Sea Race starting the 20th of october from Malta.

As in our view the boat now sails up to 85-90% of its full potential we will make some training sessions during the winter in order to optimize our sails and we will also try some differents settings of the boat

 

Kuka-Light

Some info on the rotating wing mast from Doug(found on SA) :

So, I have to assume you mean mast cant and not rake. We have all lashed standing rigging (top and bottom) and we do not move the rake or cant while underway. Not yet anyway. We have done some studies with the effectiveness of cant, combined in fact with higher angle keel cants (like ... wait for it ... Speeddream) but opted against this, not because the gains were not there, but because of complexity. It can still be revisited. Rotation of the mast is achieved through three sets of small tackle. It is both limited as with any cat rig (pulled toward CL), but also induced, due to the relatively low boom compression compared to mast compression.

The running rigging is pretty straightforward. Perhaps more than I would like, personally. The owner was very set against running anything below decks in tubes. He simply wants to see everything that is going on. For the solent we have a floating ring type lead (common on Class 40). All headsail sheets are cross sheeted always. Halyards all locked except Solent, due to reef. Tack lines all jammed on deck. Lots of lashed rings and few blocks. The main is trimmed like an X40 cat - full beam trav to winch and a hydraulic sheet, no vang. If you sail cats, no need to explain. If you sail most monos, think of the sheet on this boat like a vang - in charge of leach tension. Think of the trav like a sheet - in charge of angle of boom. We have a set of runners (now at topmast) and are experimenting with deflectors in the off season. We deal in dreams...

Doug Schickler
Schickler Tagliapietra Yacht Engineering
www.styacht.com
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Not great video but worth taking a look at:
http://www.youtube.com/watch?feature=player_embedded&v=_rm-nrbWtaI